Page 1
Page 2
Page 3
The Project Gutenberg eBook of A Practical Treatise on Gas-light
This eBook is for the use of anyone anywhere in the United States and most other parts of the
world at no cost and with almost no restrictions whatsoever. You may copy it, give it away or
re-use it under the terms of the Project Gutenberg License included with this eBook or online
at www.gutenberg.org. If you are not located in the United States, you will have to check the
laws of the country where you are located before using this eBook.
Title: A Practical Treatise on Gas-light
Author: Friedrich Christian Accum
Release date: January 2, 2014 [eBook #44567]
Most recently updated: October 23, 2024
Language: English
Other information and formats: www.gutenberg.org/ebooks/44567
Credits: Produced by Chris Curnow, Harry Lamé and the Online
Distributed Proofreading Team at http://www.pgdp.net (This
file was produced from images generously made available
by The Internet Archive)
*** START OF THE PROJECT GUTENBERG EBOOK A PRACTICAL TREATISE ON
GAS-LIGHT ***
Please see the Transcriber’s Notes at the end of
this text.
This eBook is for the use of anyone anywhere in the United States and most other parts of the
world at no cost and with almost no restrictions whatsoever. You may copy it, give it away or
re-use it under the terms of the Project Gutenberg License included with this eBook or online
at www.gutenberg.org. If you are not located in the United States, you will have to check the
laws of the country where you are located before using this eBook.
Title: A Practical Treatise on Gas-light
Author: Friedrich Christian Accum
Release date: January 2, 2014 [eBook #44567]
Most recently updated: October 23, 2024
Language: English
Other information and formats: www.gutenberg.org/ebooks/44567
Credits: Produced by Chris Curnow, Harry Lamé and the Online
Distributed Proofreading Team at http://www.pgdp.net (This
file was produced from images generously made available
by The Internet Archive)
*** START OF THE PROJECT GUTENBERG EBOOK A PRACTICAL TREATISE ON
GAS-LIGHT ***
Please see the Transcriber’s Notes at the end of
this text.
Page 4
Larger image (546 kB)
A
PRACTICAL TREATISE
ON
GAS-LIGHT;
EXHIBITING
A SUMMARY DESCRIPTION
OF THE
APPARATUS AND MACHINERY
BEST CALCULATED FOR
I L L U M I N AT I N G
STREETS, HOUSES, AND MANUFACTORIES,
WITH
A
PRACTICAL TREATISE
ON
GAS-LIGHT;
EXHIBITING
A SUMMARY DESCRIPTION
OF THE
APPARATUS AND MACHINERY
BEST CALCULATED FOR
I L L U M I N AT I N G
STREETS, HOUSES, AND MANUFACTORIES,
WITH
Page 5
CARBURETTED HYDROGEN, OR COAL-GAS,
WITH REMARKS
ON THE
UTILITY, SAFETY, AND GENERAL NATURE OF THIS NEW BRANCH
OF CIVIL ECONOMY.
By FREDRICK ACCUM,
OPERATIVE CHEMIST,
LECTURER ON PRACTICAL CHEMISTRY, ON MINERALOGY, AND ON CHEMISTRY
APPLIED TO THE ARTS AND MANUFACTURES; MEMBER OF THE ROYAL
IRISH ACADEMY, FELLOW OF THE LINNÆN SOCIETY, MEMBER
OF THE ROYAL ACADEMY OF SCIENCES OF BERLIN, &c. &c.
WITH SEVEN COLOURED PLATES.
London:
PRINTED BY G. HAYDEN, BRYDGES-STREET, COVENT GARDEN;
FOR R. ACKERMANN, 101, STRAND;
LONGMAN, HURST, REES, ORME, AND BROWN; AND SHERWOOD, NEELY, AND
JONES, PATERNOSTER ROW; AND J. HATCHARD, PICCADILLY.
Price—Twelve Shillings in Boards.
1815.
EX FUMO DARE LUCEM.
Hor.
WITH REMARKS
ON THE
UTILITY, SAFETY, AND GENERAL NATURE OF THIS NEW BRANCH
OF CIVIL ECONOMY.
By FREDRICK ACCUM,
OPERATIVE CHEMIST,
LECTURER ON PRACTICAL CHEMISTRY, ON MINERALOGY, AND ON CHEMISTRY
APPLIED TO THE ARTS AND MANUFACTURES; MEMBER OF THE ROYAL
IRISH ACADEMY, FELLOW OF THE LINNÆN SOCIETY, MEMBER
OF THE ROYAL ACADEMY OF SCIENCES OF BERLIN, &c. &c.
WITH SEVEN COLOURED PLATES.
London:
PRINTED BY G. HAYDEN, BRYDGES-STREET, COVENT GARDEN;
FOR R. ACKERMANN, 101, STRAND;
LONGMAN, HURST, REES, ORME, AND BROWN; AND SHERWOOD, NEELY, AND
JONES, PATERNOSTER ROW; AND J. HATCHARD, PICCADILLY.
Price—Twelve Shillings in Boards.
1815.
EX FUMO DARE LUCEM.
Hor.
Page 6
PREFACE.
11, Compton Street Soho.
The following pages are intended to exhibit a summary view of the new art of procuring
light, by means of carburetted hydrogen gas obtained from pit-coal, and which of late has
been employed with unparalelled success, as a substitute for candles and lamps, and is known
by the name of Gas-Light.
To accomplish this object, I have given, in the first part of this Essay, a concise and popular
view of the chemical theory and production of artificial light—I have explained the action of
candles and lamps—I have shown the methods of measuring the comparative illuminating
power of artificial light of different kinds, so as to appreciate their economical value—I have
stated the proportions of combustible materials requisite for producing a light of a certain
strength; with such other preliminary facts and observations as were deemed necessary to
enable the reader to understand fully the nature of the new art of illumination, which it is the
object of this Essay to describe.
These positions are followed by a chemical view of the general nature and composition of
coal—the chemical changes which this substance suffers, when employed in the production
of gas-light—the different products it furnishes—the modes of obtaining them—their
properties and applications in the various arts of life.
I have given a description of the apparatus and machinery by means of which the coal-gas is
prepared, and the methods employed for distributing and applying it as a substitute for
candles and lamps to illuminate houses, streets and manufactories;—I have furnished the data
for calculating the expense that must attend the application of this species of light under
different circumstances, so as to determine the relative cost or value of gas-lights, when
compared with the lights now in use—together with such other practical directions and facts
as will enable the reader to form a proper estimate of the gas-light illumination, and to put
this art into practice.
I have stated the leading objects of public and private utility to which the new system of
lighting may be successfully applied, candidly pointing out those in which it cannot be made
use of to advantage.
I have detailed the most obvious effects which the discovery of lighting with coal-gas must
inevitably produce upon the arts and upon domestic economy; its primary advantages—its
views—its limits, and the resources it presents to industry and public economy. I have
endeavoured to show how far its application is safe, and in what respect it is entitled to public
approbation and national encouragement.
11, Compton Street Soho.
The following pages are intended to exhibit a summary view of the new art of procuring
light, by means of carburetted hydrogen gas obtained from pit-coal, and which of late has
been employed with unparalelled success, as a substitute for candles and lamps, and is known
by the name of Gas-Light.
To accomplish this object, I have given, in the first part of this Essay, a concise and popular
view of the chemical theory and production of artificial light—I have explained the action of
candles and lamps—I have shown the methods of measuring the comparative illuminating
power of artificial light of different kinds, so as to appreciate their economical value—I have
stated the proportions of combustible materials requisite for producing a light of a certain
strength; with such other preliminary facts and observations as were deemed necessary to
enable the reader to understand fully the nature of the new art of illumination, which it is the
object of this Essay to describe.
These positions are followed by a chemical view of the general nature and composition of
coal—the chemical changes which this substance suffers, when employed in the production
of gas-light—the different products it furnishes—the modes of obtaining them—their
properties and applications in the various arts of life.
I have given a description of the apparatus and machinery by means of which the coal-gas is
prepared, and the methods employed for distributing and applying it as a substitute for
candles and lamps to illuminate houses, streets and manufactories;—I have furnished the data
for calculating the expense that must attend the application of this species of light under
different circumstances, so as to determine the relative cost or value of gas-lights, when
compared with the lights now in use—together with such other practical directions and facts
as will enable the reader to form a proper estimate of the gas-light illumination, and to put
this art into practice.
I have stated the leading objects of public and private utility to which the new system of
lighting may be successfully applied, candidly pointing out those in which it cannot be made
use of to advantage.
I have detailed the most obvious effects which the discovery of lighting with coal-gas must
inevitably produce upon the arts and upon domestic economy; its primary advantages—its
views—its limits, and the resources it presents to industry and public economy. I have
endeavoured to show how far its application is safe, and in what respect it is entitled to public
approbation and national encouragement.
Page 7
It may not be improper, before concluding, to inform the reader, that my qualifications for the
task I have undertaken are founded upon many years experience, during which time, I
possessed peculiar opportunities to witness and verify the most extended series of operations
that ever have been made for the purpose of ascertaining the practicability, safety, and general
nature of the art of applying coal-gas as a substitute for tallow and oil; and which have, as it
were, fixed the fate of this art. The numerous experiments I instituted, upon a large scale, by
desire of the Gas-Light Company, for the purpose of adducing them in my evidence before
the House of Commons, and House of Lords, on a former occasion, have enabled me to
collect such information as could not have been obtained by other means. The substance of
these results (which are printed by order of Government,) are incorporated in this Treatise,
together with such other facts and observations as have presented themselves in the routine of
my profession elsewhere.
To generalize the results of my observations, and to make them practically useful to the
public, is the aim of the present publication, and I need scarcely add, that their suffrages to
the zeal and industry, at least, with which I have endeavoured to attain my object, will be a
source of infinite satisfaction.
FREDRICK ACCUM
task I have undertaken are founded upon many years experience, during which time, I
possessed peculiar opportunities to witness and verify the most extended series of operations
that ever have been made for the purpose of ascertaining the practicability, safety, and general
nature of the art of applying coal-gas as a substitute for tallow and oil; and which have, as it
were, fixed the fate of this art. The numerous experiments I instituted, upon a large scale, by
desire of the Gas-Light Company, for the purpose of adducing them in my evidence before
the House of Commons, and House of Lords, on a former occasion, have enabled me to
collect such information as could not have been obtained by other means. The substance of
these results (which are printed by order of Government,) are incorporated in this Treatise,
together with such other facts and observations as have presented themselves in the routine of
my profession elsewhere.
To generalize the results of my observations, and to make them practically useful to the
public, is the aim of the present publication, and I need scarcely add, that their suffrages to
the zeal and industry, at least, with which I have endeavoured to attain my object, will be a
source of infinite satisfaction.
FREDRICK ACCUM
Page 8
Contents.
INTRODUCTORY OBSERVATION. Page 1.
Progress of the arts.—Influence of it upon the morals and condition of man.—Beneficial
tendency of chemical and mechanical improvements.—State of pre-eminence of people with
regard to civilization.—How to be estimated.—Flourishing state of those nations which have
shown the greatest activity in cultivating the useful arts, and establishing useful enterprises.
—General observations on this subject.—Extraordinary discoveries of modern times.—New
art of procuring light.—Object of the treatise.
PART I.
PRODUCTION OF ARTIFICIAL LIGHT, &c. 8.
Production of the flame generated during the combustion of certain bodies.—Characters of
flame when perfect.—Most luminous flame, how produced with the least consumption of
combustible matter.—Conditions necessary for that purpose.—Importance of this subject,
with regard to the production and supply of artificial light.—The flame of bodies may be
tinged.—Blue flame, red flame, green flame, &c.—Opinion concerning the origin of light
emitted by bodies burning with flame.—Philosophy of the subject.—Theory of the action of
the instruments of illumination.—Rude method of procuring light employed in some
countries.—Chemical action of candles, and lamps.—Agency of the tallow, oil, &c.—Office
of the wick.—Reason why tallow candles require snuffing, and wax candles snuff themselves
—Further observations on the subject.
METHOD OF ASCERTAINING THE ILLUMINATING POWER OF CANDLES,
LAMPS, AND OTHER LUMINOUS BODIES. 22.
Optical principle assumed as law for determining the relative strength of lights of different
kinds.—Admeasurement of the intensities of light.—Quantity of wax, tallow, oil, &c.
requisite for producing a light of a certain strength.—Method of increasing the light of tallow
candles, and to obviate the necessity of snuffing them.—A tallow candle placed in an
inclined position gives more light than when placed perpendicularly and snuffed with an
instrument.—Explanation of the fact.—Further observations on this subject.—Comparative
cost of the light obtained by burning tallow candles of different sorts and sizes.
PART II.
INTRODUCTORY OBSERVATION. Page 1.
Progress of the arts.—Influence of it upon the morals and condition of man.—Beneficial
tendency of chemical and mechanical improvements.—State of pre-eminence of people with
regard to civilization.—How to be estimated.—Flourishing state of those nations which have
shown the greatest activity in cultivating the useful arts, and establishing useful enterprises.
—General observations on this subject.—Extraordinary discoveries of modern times.—New
art of procuring light.—Object of the treatise.
PART I.
PRODUCTION OF ARTIFICIAL LIGHT, &c. 8.
Production of the flame generated during the combustion of certain bodies.—Characters of
flame when perfect.—Most luminous flame, how produced with the least consumption of
combustible matter.—Conditions necessary for that purpose.—Importance of this subject,
with regard to the production and supply of artificial light.—The flame of bodies may be
tinged.—Blue flame, red flame, green flame, &c.—Opinion concerning the origin of light
emitted by bodies burning with flame.—Philosophy of the subject.—Theory of the action of
the instruments of illumination.—Rude method of procuring light employed in some
countries.—Chemical action of candles, and lamps.—Agency of the tallow, oil, &c.—Office
of the wick.—Reason why tallow candles require snuffing, and wax candles snuff themselves
—Further observations on the subject.
METHOD OF ASCERTAINING THE ILLUMINATING POWER OF CANDLES,
LAMPS, AND OTHER LUMINOUS BODIES. 22.
Optical principle assumed as law for determining the relative strength of lights of different
kinds.—Admeasurement of the intensities of light.—Quantity of wax, tallow, oil, &c.
requisite for producing a light of a certain strength.—Method of increasing the light of tallow
candles, and to obviate the necessity of snuffing them.—A tallow candle placed in an
inclined position gives more light than when placed perpendicularly and snuffed with an
instrument.—Explanation of the fact.—Further observations on this subject.—Comparative
cost of the light obtained by burning tallow candles of different sorts and sizes.
PART II.
Page 9
GAS-LIGHT. 47.
Encouragement given by the legislature to the new system of procuring light.—Gas-light
company, incorporated by charter, to apply the new art of illumination by way of experiment,
on a large scale, to illuminate the streets and houses of the metropolis.—Power and
authorities granted to this corporate body.—are very restricted, and do not prevent other
individuals from entering into competition with them.—Boundaries of their experiments.—
limit of capital employed by them.—Power of His Majesty with regard to the gas-light
charter.
THEORY OF THE COMBUSTION OF COAL IN ELUCIDATION OF THE
NATURE OF GAS-LIGHT. 49.
Natural history of pit-coal.—Immediate constituent parts of coal.—Their relative quantities
—are different in different kinds of coal.—Phenomena, which happen during the combustion
of coal.—Analysis of coal by distillation.—Great waste of matter capable of producing light
and heat, in the usual mode of burning coal.—Proofs of this statement.—Theory of the
production of gas-light, compared with the production of light obtained by candles and
lamps.—Place which the discovery of lighting with gas occupies in the philosophical order
of knowledge.
HISTORICAL SKETCH OF THE RISE AND PROGRESS OF THE
APPLICATION OF COAL-GAS AS A SUBSTITUTE FOR PROCURING
ARTIFICIAL LIGHT. 55.
The discovery of the inflammable nature and application of coal-gas for the production of
artificial light, cannot be claimed by any body now living.—Early notices of the inflammable
property of the gas obtained by distilling coal.—Attempts to substitute it for tallow and oil.
—Experiments made with coal-gas by Dr. Clayton, Dr. Hales, and the Bishop of Llandaff.
—First successful attempt of lighting manufactories with gas.—Creditor and debtor account
concerning the expence of this mode of illumination, when compared with the light obtained
by tallow candles.—Claims of Mr. Murdoch with regard to the economical application of
coal-gas.—Claims of Mr. Winsor.—Experiments of Mr. Northern, Mr. Clegg, Mr. Cook,
Mr. Ackermann.—Economical statements of the gas-light illumination when compared with
the cost of the same quantity of light obtained by means of candles and lamps.
THEORY OF THE PRODUCTION OF GAS-LIGHT; AND DESCRIPTION OF A
PORTABLE APPARATUS FOR ILLUSTRATING, IN THE SMALL WAY, THE
GENERAL NATURE OF THE NEW SYSTEM OF PROCURING LIGHT. 77.
Philosophy of the production of coal-gas.—Characters of the various products which the gas-
light process affords, their quantities, and modes of obtaining them.—Quantity of gas
obtainable from a given weight of coal.—Illuminating power of a given bulk of coal-gas
compared with the illuminating power of a given weight of tallow candles.—Practical
directions with regard to the production of the gas from coal.—Its chemical constitution and
analysis.—Pit-coal is not the only substance which affords carburetted hidrogen gas.—This
gas exists ready formed in nature.—Mode of collecting it when found native.—Is given out
by all kinds of vegetable matter, submitted to distillation in close vessels.—Other sources of
obtaining this gazeous fluid.—Practical directions with regard to the method of obtaining
Encouragement given by the legislature to the new system of procuring light.—Gas-light
company, incorporated by charter, to apply the new art of illumination by way of experiment,
on a large scale, to illuminate the streets and houses of the metropolis.—Power and
authorities granted to this corporate body.—are very restricted, and do not prevent other
individuals from entering into competition with them.—Boundaries of their experiments.—
limit of capital employed by them.—Power of His Majesty with regard to the gas-light
charter.
THEORY OF THE COMBUSTION OF COAL IN ELUCIDATION OF THE
NATURE OF GAS-LIGHT. 49.
Natural history of pit-coal.—Immediate constituent parts of coal.—Their relative quantities
—are different in different kinds of coal.—Phenomena, which happen during the combustion
of coal.—Analysis of coal by distillation.—Great waste of matter capable of producing light
and heat, in the usual mode of burning coal.—Proofs of this statement.—Theory of the
production of gas-light, compared with the production of light obtained by candles and
lamps.—Place which the discovery of lighting with gas occupies in the philosophical order
of knowledge.
HISTORICAL SKETCH OF THE RISE AND PROGRESS OF THE
APPLICATION OF COAL-GAS AS A SUBSTITUTE FOR PROCURING
ARTIFICIAL LIGHT. 55.
The discovery of the inflammable nature and application of coal-gas for the production of
artificial light, cannot be claimed by any body now living.—Early notices of the inflammable
property of the gas obtained by distilling coal.—Attempts to substitute it for tallow and oil.
—Experiments made with coal-gas by Dr. Clayton, Dr. Hales, and the Bishop of Llandaff.
—First successful attempt of lighting manufactories with gas.—Creditor and debtor account
concerning the expence of this mode of illumination, when compared with the light obtained
by tallow candles.—Claims of Mr. Murdoch with regard to the economical application of
coal-gas.—Claims of Mr. Winsor.—Experiments of Mr. Northern, Mr. Clegg, Mr. Cook,
Mr. Ackermann.—Economical statements of the gas-light illumination when compared with
the cost of the same quantity of light obtained by means of candles and lamps.
THEORY OF THE PRODUCTION OF GAS-LIGHT; AND DESCRIPTION OF A
PORTABLE APPARATUS FOR ILLUSTRATING, IN THE SMALL WAY, THE
GENERAL NATURE OF THE NEW SYSTEM OF PROCURING LIGHT. 77.
Philosophy of the production of coal-gas.—Characters of the various products which the gas-
light process affords, their quantities, and modes of obtaining them.—Quantity of gas
obtainable from a given weight of coal.—Illuminating power of a given bulk of coal-gas
compared with the illuminating power of a given weight of tallow candles.—Practical
directions with regard to the production of the gas from coal.—Its chemical constitution and
analysis.—Pit-coal is not the only substance which affords carburetted hidrogen gas.—This
gas exists ready formed in nature.—Mode of collecting it when found native.—Is given out
by all kinds of vegetable matter, submitted to distillation in close vessels.—Other sources of
obtaining this gazeous fluid.—Practical directions with regard to the method of obtaining
Page 10
from coal, this gazeous substance, as best suited for illumination.—Chemical constitution of
coal-gas.—How ascertained.
UTILITY OF THE GAS-LIGHT ILLUMINATION WITH REGARD TO PUBLIC
AND PRIVATE ECONOMY. 99.
Objects to which the new system of lighting with gas may be beneficially applied.—Capital
advantages of the gas-light illumination.—Places and public edifices lighted with coal-gas in
this metropolis.—Situations best suited for the application of gas-lights.—places where it
cannot be used to advantage.—Illumination of barracks, arsenals, dock yards, &c. with coal-
gas.—Further observations on this subject.—Great heat produced by gas-lights.—Reason
why the flame of coal-gas produces more heat than the flame of candles and lamps.—
Admeasurement of the comparative degrees of heat produced by gas-lights, oil lamps, tallow
and wax candles, &c.—Gas lamps and burners, various kinds of.—Ornamental chandeliers
and candelabras, for applying coal-gas as a substitute for oil.—Other products obtainable
from coal besides gas.—Coke.—Its nature.—Combustion of it.—Produces a more strong and
lasting heat than coal.—Explanation of this fact.—Advantages resulting from the use of coke
as fuel.—Disadvantages of its application in certain circumstances.—Relative effect of heat
produced by equal quantities of coke and charcoal.—Method of measuring the comparative
effect of different kinds of fuel in producing heat.—Capital advantages resulting from the
application of coke, as fuel, in the art of burning lime.—Plaster of Paris, bricks, &c.—
Quantity of coke obtainable from a certain quantity of pit-coal.—Kind of coke best suited for
metallurgical operations.—Mode of obtaining it in the gas-light process.—Sort of coke best
adapted for kitchen and parlour fires.—Manufacture of it.—Coal tar.—How obtained.—Its
properties.—Earl of Dundonald’s method of manufacturing tar from coal.—Quantity of coal-
tar produced in the gas-light process from a given quantity of coal.—Characters of coal tar
obtained from Newcastle coal, differ from that produced from canel coal.—Coal pitch.—
Process for obtaining it.—Properties of coal-pitch.—Use of it in the arts.—quantity of coal-
pitch obtainable from a given quantity of tar.—Ammoniacal liquor produced during the
distillation of coal.—Its chemical constitution.—Quantity obtained from a given quantity of
coal.—General observation respecting the scheme of applying coal-gas as a substitute for
candles and lamps.—Effects which it must produce upon the arts and upon domestic
economy.—Its views.—Primary advantages.—Resources which it presents to industry and
public economy.—In what respect it is entitled to public approbation and national
encouragement.—Effects of prejudice against the introduction of new and useful discoveries.
—Have operated strongly in retarding the gas-light illumination.—Remarkable slowness
with which improvements of extended utility make their way into common use, contrasted
with the rapid adoption of fashionable changes.—Other causes unfavourable to the adoption
of new and useful plans.—Further observations on this subject.—The new system of lighting
with coal-gas can never supersede the use of candles and moveable lights.—Gas-light
illumination cannot prove injurious to the Greenland fishery—nor can it diminish the coal
trade—must prove beneficial to it.—The price of coal even when it is the highest cannot
materially affect the beneficial application of gas-lights.—Striking advantages to be derived
from the introduction of gas-lights into manufactories.—Principal expense which must
always attend the gas-light illumination.—Is the dead capital employed for erecting the
machinery.—Floating capital is small.—Advice to private individuals with regard to the
erection of a gas-light apparatus calculated for their own use.—Expence which must attend
coal-gas.—How ascertained.
UTILITY OF THE GAS-LIGHT ILLUMINATION WITH REGARD TO PUBLIC
AND PRIVATE ECONOMY. 99.
Objects to which the new system of lighting with gas may be beneficially applied.—Capital
advantages of the gas-light illumination.—Places and public edifices lighted with coal-gas in
this metropolis.—Situations best suited for the application of gas-lights.—places where it
cannot be used to advantage.—Illumination of barracks, arsenals, dock yards, &c. with coal-
gas.—Further observations on this subject.—Great heat produced by gas-lights.—Reason
why the flame of coal-gas produces more heat than the flame of candles and lamps.—
Admeasurement of the comparative degrees of heat produced by gas-lights, oil lamps, tallow
and wax candles, &c.—Gas lamps and burners, various kinds of.—Ornamental chandeliers
and candelabras, for applying coal-gas as a substitute for oil.—Other products obtainable
from coal besides gas.—Coke.—Its nature.—Combustion of it.—Produces a more strong and
lasting heat than coal.—Explanation of this fact.—Advantages resulting from the use of coke
as fuel.—Disadvantages of its application in certain circumstances.—Relative effect of heat
produced by equal quantities of coke and charcoal.—Method of measuring the comparative
effect of different kinds of fuel in producing heat.—Capital advantages resulting from the
application of coke, as fuel, in the art of burning lime.—Plaster of Paris, bricks, &c.—
Quantity of coke obtainable from a certain quantity of pit-coal.—Kind of coke best suited for
metallurgical operations.—Mode of obtaining it in the gas-light process.—Sort of coke best
adapted for kitchen and parlour fires.—Manufacture of it.—Coal tar.—How obtained.—Its
properties.—Earl of Dundonald’s method of manufacturing tar from coal.—Quantity of coal-
tar produced in the gas-light process from a given quantity of coal.—Characters of coal tar
obtained from Newcastle coal, differ from that produced from canel coal.—Coal pitch.—
Process for obtaining it.—Properties of coal-pitch.—Use of it in the arts.—quantity of coal-
pitch obtainable from a given quantity of tar.—Ammoniacal liquor produced during the
distillation of coal.—Its chemical constitution.—Quantity obtained from a given quantity of
coal.—General observation respecting the scheme of applying coal-gas as a substitute for
candles and lamps.—Effects which it must produce upon the arts and upon domestic
economy.—Its views.—Primary advantages.—Resources which it presents to industry and
public economy.—In what respect it is entitled to public approbation and national
encouragement.—Effects of prejudice against the introduction of new and useful discoveries.
—Have operated strongly in retarding the gas-light illumination.—Remarkable slowness
with which improvements of extended utility make their way into common use, contrasted
with the rapid adoption of fashionable changes.—Other causes unfavourable to the adoption
of new and useful plans.—Further observations on this subject.—The new system of lighting
with coal-gas can never supersede the use of candles and moveable lights.—Gas-light
illumination cannot prove injurious to the Greenland fishery—nor can it diminish the coal
trade—must prove beneficial to it.—The price of coal even when it is the highest cannot
materially affect the beneficial application of gas-lights.—Striking advantages to be derived
from the introduction of gas-lights into manufactories.—Principal expense which must
always attend the gas-light illumination.—Is the dead capital employed for erecting the
machinery.—Floating capital is small.—Advice to private individuals with regard to the
erection of a gas-light apparatus calculated for their own use.—Expence which must attend
Page 11
the application of the new system of lighting under different circumstances.—Entire new
scheme of illuminating streets, or small towns, with gas-lights; which would save all the
main pipes for conveying the gas through the streets as well as the branch pipes which
conduct the gas to the lamps.—Management of the gas-light machinery is extremely simple
and easy.—The apparatus not liable to be out of order.—Observations on the safety of the
gas-light illumination.—Misapprehension of the public concerning it.—Causes that have
alarmed the public concerning the application of the new lights.—Gas-lights cannot give rise
to those accidents which have so often arisen from the careless snuffing of candles, &c.—
Produce no embers or sparks.—Cannot fall, or be disturbed without becoming extinguished.
—Are the safest of all lights.—Impossibility of streets or towns lighted with gas to be thrown
suddenly into darkness by the fracture of the gas-pipes conveying the gas to the lamps—or
by the destruction of one or more of the gas-light machineries employed for preparing the
gas.—Illustration showing the absurdity of such mistaken notions.—Curious self-
extinguishing lamp, invented by Mr. Clegg.—His machine which measures and registers in
the absence of the observer, the quantity of gas delivered by a pipe communicating with a
gas-light main.—Leading characters of the new lights.—Objects and views which this art
embraces.—It must lessen the consumption of oil.—Occasion a defalcation in the revenue.
TABULAR VIEW, Exhibiting the quantity of Gas, Coke, Tar, Pitch, Essential Oil,
and Ammoniacal Liquor, obtainable from a given quantity of Coal: together with an
estimate of the quantity of Coal necessary to produce a quantity of Gas, capable of
yielding a Light equal in duration of time and intensity to that produced by Tallow
Candles of different kinds. 164.
DESCRIPTION OF THE GAS-LIGHT APPARATUS. 166.
METHOD of correcting the relative pressure of the Gasometer, so as to cause the gas
which it contains to be uniformly of an equal density. 181.
DIRECTIONS TO WORKMEN ATTENDING THE GAS-LIGHT APPARATUS. 182.
ESTIMATE of the price of a Gas-Light Apparatus. 185.
LONDON Price List of the most essential articles employed in the erection of a Gas-
light Apparatus. 186.
scheme of illuminating streets, or small towns, with gas-lights; which would save all the
main pipes for conveying the gas through the streets as well as the branch pipes which
conduct the gas to the lamps.—Management of the gas-light machinery is extremely simple
and easy.—The apparatus not liable to be out of order.—Observations on the safety of the
gas-light illumination.—Misapprehension of the public concerning it.—Causes that have
alarmed the public concerning the application of the new lights.—Gas-lights cannot give rise
to those accidents which have so often arisen from the careless snuffing of candles, &c.—
Produce no embers or sparks.—Cannot fall, or be disturbed without becoming extinguished.
—Are the safest of all lights.—Impossibility of streets or towns lighted with gas to be thrown
suddenly into darkness by the fracture of the gas-pipes conveying the gas to the lamps—or
by the destruction of one or more of the gas-light machineries employed for preparing the
gas.—Illustration showing the absurdity of such mistaken notions.—Curious self-
extinguishing lamp, invented by Mr. Clegg.—His machine which measures and registers in
the absence of the observer, the quantity of gas delivered by a pipe communicating with a
gas-light main.—Leading characters of the new lights.—Objects and views which this art
embraces.—It must lessen the consumption of oil.—Occasion a defalcation in the revenue.
TABULAR VIEW, Exhibiting the quantity of Gas, Coke, Tar, Pitch, Essential Oil,
and Ammoniacal Liquor, obtainable from a given quantity of Coal: together with an
estimate of the quantity of Coal necessary to produce a quantity of Gas, capable of
yielding a Light equal in duration of time and intensity to that produced by Tallow
Candles of different kinds. 164.
DESCRIPTION OF THE GAS-LIGHT APPARATUS. 166.
METHOD of correcting the relative pressure of the Gasometer, so as to cause the gas
which it contains to be uniformly of an equal density. 181.
DIRECTIONS TO WORKMEN ATTENDING THE GAS-LIGHT APPARATUS. 182.
ESTIMATE of the price of a Gas-Light Apparatus. 185.
LONDON Price List of the most essential articles employed in the erection of a Gas-
light Apparatus. 186.
Page 12
ERRATA.
Page 24, line 11, for too, read two.
48, 22, for corporated, read incorporated.
53, 7, for this combustion, read the combustion.
64, 24, for Cleg, read Clegg.
ibid 25, for communicates, read communicated.
65, erase the * and put it after the word Clegg, line 24, p. 64.
ibid 17, for attemps, read attempts.
125, 23, for degree, read degrees.
132, 25, for coal, read coal-tar.
Page 24, line 11, for too, read two.
48, 22, for corporated, read incorporated.
53, 7, for this combustion, read the combustion.
64, 24, for Cleg, read Clegg.
ibid 25, for communicates, read communicated.
65, erase the * and put it after the word Clegg, line 24, p. 64.
ibid 17, for attemps, read attempts.
125, 23, for degree, read degrees.
132, 25, for coal, read coal-tar.
Page 13
DIRECTIONS TO THE BINDER:
Plate I. facing the title; plate II. facing page 79; plate III. facing page 115; plate IV. facing page 119; plate V. facing page
120; and plates VI. and VII. at the end of the book.
A
PRACTICAL TREATISE
ON
GAS-LIGHT.
Plate I. facing the title; plate II. facing page 79; plate III. facing page 115; plate IV. facing page 119; plate V. facing page
120; and plates VI. and VII. at the end of the book.
A
PRACTICAL TREATISE
ON
GAS-LIGHT.
Page 14
INTRODUCTORY OBSERVATION.
INFLUENCE
OF
THE PROGRESS OF THE ARTS
UPON THE
MORALS AND CONDITION OF MAN.
It is an undoubted truth, that the successive improvements in the condition of man, from a
state of ignorance and barbarism, to that of the highest cultivation and refinement, are usually
effected by the aid of machinery and expedients, calculated to procure the necessaries, the
comforts, and the elegancies of life; and that the pre-eminence of any people in civilization
is, and ought ever to be, estimated by the proportional state of industry, and useful labour
existing among them.
In proof of this great and striking truth, no other argument requires to be offered, than an
immediate reference to the experience of all ages and places: the various nations of the earth,
the provinces of each nation, the towns, and even the villages of the same province, differ
from each other in their accommodations; and are in every respect more flourishing, the
greater their activity in establishing new channels of useful employ, calculated to procure the
necessaries and comforts of life. Hence the nations which have shewn the most ingenuity in
this way, are not only the richest, but also the most populous and the best defended: the
provinces of those nations, are seen to flourish likewise in proportion to their respective
degrees of activity in this respect, And from these exertions it is, as Smith[1] emphatically
remarks, that “the accommodation of an European prince does not always so much exceed
that of an industrious and frugal peasant, as the accommodation of the latter exceeds that of
many an African king, the absolute master of the lives and liberties of ten thousand naked
savages.”
[1] Wealth of Nations, chap. 1.
It was a strange notion of Rousseau to maintain that mankind were happier when they
resembled wild beasts, than with all the expanded knowledge of civilized life; and that the
cultivation of their understanding had tended to degenerate their virtues. There can be no
virtue but what is founded on a comprehensive estimate of the effects of human actions, and
an animal under the guidance of instinct can form no such estimate.
The variety of production, of wants, and fabrication of a civilized society, has given rise to
barter or exchange; mutual supply has increased the sub-division of labour, and improved the
INFLUENCE
OF
THE PROGRESS OF THE ARTS
UPON THE
MORALS AND CONDITION OF MAN.
It is an undoubted truth, that the successive improvements in the condition of man, from a
state of ignorance and barbarism, to that of the highest cultivation and refinement, are usually
effected by the aid of machinery and expedients, calculated to procure the necessaries, the
comforts, and the elegancies of life; and that the pre-eminence of any people in civilization
is, and ought ever to be, estimated by the proportional state of industry, and useful labour
existing among them.
In proof of this great and striking truth, no other argument requires to be offered, than an
immediate reference to the experience of all ages and places: the various nations of the earth,
the provinces of each nation, the towns, and even the villages of the same province, differ
from each other in their accommodations; and are in every respect more flourishing, the
greater their activity in establishing new channels of useful employ, calculated to procure the
necessaries and comforts of life. Hence the nations which have shewn the most ingenuity in
this way, are not only the richest, but also the most populous and the best defended: the
provinces of those nations, are seen to flourish likewise in proportion to their respective
degrees of activity in this respect, And from these exertions it is, as Smith[1] emphatically
remarks, that “the accommodation of an European prince does not always so much exceed
that of an industrious and frugal peasant, as the accommodation of the latter exceeds that of
many an African king, the absolute master of the lives and liberties of ten thousand naked
savages.”
[1] Wealth of Nations, chap. 1.
It was a strange notion of Rousseau to maintain that mankind were happier when they
resembled wild beasts, than with all the expanded knowledge of civilized life; and that the
cultivation of their understanding had tended to degenerate their virtues. There can be no
virtue but what is founded on a comprehensive estimate of the effects of human actions, and
an animal under the guidance of instinct can form no such estimate.
The variety of production, of wants, and fabrication of a civilized society, has given rise to
barter or exchange; mutual supply has increased the sub-division of labour, and improved the
Page 15
means of conveyance. Streams, roads, ships, and carriages have extended their beneficial
intercourse; confidence between man and man has advanced the moral principles of society,
and afforded a progression, of which the past gradation may indeed be traced, but to the
future part of which the imagination can scarcely form a probable outline. And as the moral
and physical powers of man expand, new resources and new agencies are made subservient
to our commands, which, in an earlier state of society, would have appeared altogether
visionary.
Who among the ancients would have listened to the extraordinary scheme of writing books
with such rapidity, that one man, by this new art, should perform the work of twenty
thousand amanuenses? What philosopher would have given credit to the daring project of
navigating the widest ocean?—or imagined the astonishing effect of gun-powder—or the
extended application of the steam engine? What mortal would have dared to dive to the
bottom of the sea—or to soar aloft into the air—or bid defiance to the thunder of the clouds?
Discoveries which have changed, as it were, the course of human affairs, and the effects of
which have already carried the intellectual operations of the human mind, to a height they
could by no other means have attained. The men of those early ages, in the confidence of
their own wisdom, might have derided these discoveries as impossible, or rejected them as
visionary; but to those, who enjoy the full effects of such, and numerous other successful
inventions, it becomes a duty to reason upon different principles, and to exert all means in
their power to give effect to the progress of useful knowledge.
The artificial production and supply of light during the absence of the sun, unquestionably
holds a distinguished rank among the most important arts of civilized life.
If we could for a moment suppose the privation of artificial light, it would follow as an
immediate consequence that the greatest part of the globe on which we dwell, would cease to
be the habitation of man. Whether he could ensnare or overtake those animals upon whose
unprepared remains he would then be compelled to feed—whether he might store the fruits
of the earth for his winter supply—what might be the physical and moral consequences of a
state of such desolation, may perhaps be conjectured; but no estimate can show its dreadful
magnitude. How much do our comforts, and how greatly does the extent of our powers, in the
common affairs of life, depend upon the production and supply of artificial light. The flame
of a single candle animates a family, every one follows his occupation, and no dread is felt of
the darkness of night. It might be a curious speculation to enquire how far, and in what
respects, the morals of men would become degraded by the want of this contrivance. But it is
sufficient on the present occasion, that, previous to entering upon a dissertation respecting a
new art of illumination, a train of ideas has slightly been hinted at, which cannot fail to show
its magnitude and importance. The methods of procuring and distributing light, during the
absence of the sun, have not hitherto attained the extent of their possible perfection: there is
yet a wide field for improvement in the construction of the instruments of illumination, and
the subject is highly deserving the attention of every individual.
The scheme of lighting houses, streets, and manufactories, by means of the inflammable gas,
obtainable by distillation from common pit-coal, professes to increase the wealth of the
nation, by adding to the number of its internal resources, and on this ground it is entitled, at
least, to a candid examination.
intercourse; confidence between man and man has advanced the moral principles of society,
and afforded a progression, of which the past gradation may indeed be traced, but to the
future part of which the imagination can scarcely form a probable outline. And as the moral
and physical powers of man expand, new resources and new agencies are made subservient
to our commands, which, in an earlier state of society, would have appeared altogether
visionary.
Who among the ancients would have listened to the extraordinary scheme of writing books
with such rapidity, that one man, by this new art, should perform the work of twenty
thousand amanuenses? What philosopher would have given credit to the daring project of
navigating the widest ocean?—or imagined the astonishing effect of gun-powder—or the
extended application of the steam engine? What mortal would have dared to dive to the
bottom of the sea—or to soar aloft into the air—or bid defiance to the thunder of the clouds?
Discoveries which have changed, as it were, the course of human affairs, and the effects of
which have already carried the intellectual operations of the human mind, to a height they
could by no other means have attained. The men of those early ages, in the confidence of
their own wisdom, might have derided these discoveries as impossible, or rejected them as
visionary; but to those, who enjoy the full effects of such, and numerous other successful
inventions, it becomes a duty to reason upon different principles, and to exert all means in
their power to give effect to the progress of useful knowledge.
The artificial production and supply of light during the absence of the sun, unquestionably
holds a distinguished rank among the most important arts of civilized life.
If we could for a moment suppose the privation of artificial light, it would follow as an
immediate consequence that the greatest part of the globe on which we dwell, would cease to
be the habitation of man. Whether he could ensnare or overtake those animals upon whose
unprepared remains he would then be compelled to feed—whether he might store the fruits
of the earth for his winter supply—what might be the physical and moral consequences of a
state of such desolation, may perhaps be conjectured; but no estimate can show its dreadful
magnitude. How much do our comforts, and how greatly does the extent of our powers, in the
common affairs of life, depend upon the production and supply of artificial light. The flame
of a single candle animates a family, every one follows his occupation, and no dread is felt of
the darkness of night. It might be a curious speculation to enquire how far, and in what
respects, the morals of men would become degraded by the want of this contrivance. But it is
sufficient on the present occasion, that, previous to entering upon a dissertation respecting a
new art of illumination, a train of ideas has slightly been hinted at, which cannot fail to show
its magnitude and importance. The methods of procuring and distributing light, during the
absence of the sun, have not hitherto attained the extent of their possible perfection: there is
yet a wide field for improvement in the construction of the instruments of illumination, and
the subject is highly deserving the attention of every individual.
The scheme of lighting houses, streets, and manufactories, by means of the inflammable gas,
obtainable by distillation from common pit-coal, professes to increase the wealth of the
nation, by adding to the number of its internal resources, and on this ground it is entitled, at
least, to a candid examination.
Page 16
The apparent slight that has been thrown upon this new breach of civil economy by some
individuals, who appear to be incapable of judging of its nature, has contributed to deter
sensible and well disposed persons from wishing it success. It is the more necessary to state
this fact, because, when a mistaken notion once becomes diffused, concerning the nature of a
new project, persons of the best intention are liable to become affected with wrong
impressions on their mind. I am neither a share holder, nor a governor, nor am I directly or
indirectly concerned in any gas-light association.
The object of the succeeding pages, simply is to rescue the art of illumination with coal-gas
from misconception and misrepresentation, and by a fair, and not overcharged statement of
its merits and its disadvantages, to appeal from prejudice and ignorance, to the good sense of
the community.
individuals, who appear to be incapable of judging of its nature, has contributed to deter
sensible and well disposed persons from wishing it success. It is the more necessary to state
this fact, because, when a mistaken notion once becomes diffused, concerning the nature of a
new project, persons of the best intention are liable to become affected with wrong
impressions on their mind. I am neither a share holder, nor a governor, nor am I directly or
indirectly concerned in any gas-light association.
The object of the succeeding pages, simply is to rescue the art of illumination with coal-gas
from misconception and misrepresentation, and by a fair, and not overcharged statement of
its merits and its disadvantages, to appeal from prejudice and ignorance, to the good sense of
the community.
Page 17
PART I.
PRODUCTION
OF
ARTIFICIAL LIGHT;
AND
THEORY
OF THE
ACTION OF CANDLES AND LAMPS.
The flame of burning bodies consists of such inflammable matter in the act of combustion as
is capable of existing in a gazeous state. When all circumstances are favorable to the
complete combustion of the products, the flame is perfect; if this is not the case, part of the
combustible body, capable of being converted into the gazeous state, passes through the
luminous flame unburnt, and exhibits the appearance of smoke. Soot therefore always
indicates an imperfect combustion. Hence flame is produced from those inflammable
substances only, which are either totally volatile when heat is applied to them, so as not to
alter their chemical habitudes—or which contain a quantity of combustible matter that is
readily volatilized into vapour by heat, or the elements necessary for producing such vapour
or gazeous products, when the chemical constitution of the body is altered by an increase of
temperature. And hence the flame of bodies is nothing else than the inflammable product,
either in a vaporous or in a permanently elastic gazeous state. Thus originates the flame of
wood and coal, when they are burned in their crude state. They contain the elements of a
quantity of inflammable matter, which is capable of assuming the gazeous state by the
application of heat, and subsequent new chemical arrangements of their constituent parts.
As the artificial light of lamps and candles is afforded by the flame they exhibit, it seems a
matter of considerable importance to society, to ascertain how the most luminous flame may
be produced with the least consumption of combustible matter. There does not appear to be
any danger of error in concluding, that the light emitted will be greatest when the matter is
completely consumed in the shortest time. It is therefore necessary, that the stream of
volatilized combustible gazeous matter should pass into the atmosphere with a certain
determinate velocity. If the quantity of this stream should not be duly proportioned; that is to
say, if it be too large, its internal parts will not be completely burned for want of contact with
the air. If its temperature be below that of ignition, it will not, in many cases, burn when it
comes into the open air. And there is a certain velocity at which the quantity of atmospherical
air which comes in contact with the vapour will be neither too great nor too small; for too
PRODUCTION
OF
ARTIFICIAL LIGHT;
AND
THEORY
OF THE
ACTION OF CANDLES AND LAMPS.
The flame of burning bodies consists of such inflammable matter in the act of combustion as
is capable of existing in a gazeous state. When all circumstances are favorable to the
complete combustion of the products, the flame is perfect; if this is not the case, part of the
combustible body, capable of being converted into the gazeous state, passes through the
luminous flame unburnt, and exhibits the appearance of smoke. Soot therefore always
indicates an imperfect combustion. Hence flame is produced from those inflammable
substances only, which are either totally volatile when heat is applied to them, so as not to
alter their chemical habitudes—or which contain a quantity of combustible matter that is
readily volatilized into vapour by heat, or the elements necessary for producing such vapour
or gazeous products, when the chemical constitution of the body is altered by an increase of
temperature. And hence the flame of bodies is nothing else than the inflammable product,
either in a vaporous or in a permanently elastic gazeous state. Thus originates the flame of
wood and coal, when they are burned in their crude state. They contain the elements of a
quantity of inflammable matter, which is capable of assuming the gazeous state by the
application of heat, and subsequent new chemical arrangements of their constituent parts.
As the artificial light of lamps and candles is afforded by the flame they exhibit, it seems a
matter of considerable importance to society, to ascertain how the most luminous flame may
be produced with the least consumption of combustible matter. There does not appear to be
any danger of error in concluding, that the light emitted will be greatest when the matter is
completely consumed in the shortest time. It is therefore necessary, that the stream of
volatilized combustible gazeous matter should pass into the atmosphere with a certain
determinate velocity. If the quantity of this stream should not be duly proportioned; that is to
say, if it be too large, its internal parts will not be completely burned for want of contact with
the air. If its temperature be below that of ignition, it will not, in many cases, burn when it
comes into the open air. And there is a certain velocity at which the quantity of atmospherical
air which comes in contact with the vapour will be neither too great nor too small; for too
Page 18
much air will diminish the temperature of the stream of combustible matter so much as very
considerably to impede the desired effect, and too little will render the combustion languid.
We have an example of a flame too large in the mouths of the chimneys of furnaces, where
the luminous part is merely superficial, or of the thickness of about an inch or two, according
to circumstances, and the internal part, though hot, will not set fire to paper passed into it
through an iron tube; the same defect of air preventing the combustion of the paper, as
prevented the interior fluid itself from burning. And in the lamp of Argand we see the
advantage of an internal current of air, which renders the combustion perfect by the
application of air on both sides of a thin flame. So likewise a small flame is always whiter
and more luminous than a larger; and a short snuff of a candle giving out less combustible
matter in proportion to the circumambient air; the quantity of light becomes increased to
eight or ten times what a long snuff would have afforded.
The light of bodies burning with flame, exists previously either combined with the
combustible body, or with the substance which supports the combustion. We know that light
exists in some bodies as a constituent part, since it is disengaged from them when they enter
into new combinations, but we are unable to obtain in a separate state the basis with which it
was combined.
That in many cases the light evolved by artificial means is derived from the combustible
body, is obvious, if we recollect that the colour of the light emitted during the process of
combustion varies, and that this variation usually depends not upon the medium which
supports the process of combustion, but upon the combustible body itself. Hence the colour
of the flame of certain combustibles, even of the purest kind may be tinged by the admixture
of various substances.
The flame of a common candle is far from being of an uniform colour. The lowest part is
always blue; and when the flame is sufficiently elongated, so as to be just ready to smoke, the
tip is red or brown.
As for the colours of flames that arise from coals, wood, and other usual combustibles, their
variety, which hardly amounts to a few shades of red or purple, intermixed with the bright
yellow light, seems principally to arise from the greater or less admixture of aqueous vapour,
dense smoke, or, in short, of other incombustible products which pass through the luminous
flame unburnt.
Spirit of wine burns with a blueish flame. The flame of sulphur has nearly the same tinge.
The flame of zinc is of a bright greenish white. The flame of most of the preparations of
copper, or of the substances with which they are mixed, is vivid green. Spirit of wine, mixed
with common salt, when set on fire, burns with a very unpleasant effect, as may be
experienced by looking at the spectators who are illuminated by such light. If a spoonful of
spirit of wine and a little boracic acid, or nitrate of copper be stirred together in a cup, and
then be set on fire, the flame will be beautifully green. If spirit of wine be mixed with nitrate
of strontia, it will, afterwards, on being inflamed, burn with a carmine red colour. Muriate of
lime tinges the flame of burning spirit of wine of an orange colour.[2]
considerably to impede the desired effect, and too little will render the combustion languid.
We have an example of a flame too large in the mouths of the chimneys of furnaces, where
the luminous part is merely superficial, or of the thickness of about an inch or two, according
to circumstances, and the internal part, though hot, will not set fire to paper passed into it
through an iron tube; the same defect of air preventing the combustion of the paper, as
prevented the interior fluid itself from burning. And in the lamp of Argand we see the
advantage of an internal current of air, which renders the combustion perfect by the
application of air on both sides of a thin flame. So likewise a small flame is always whiter
and more luminous than a larger; and a short snuff of a candle giving out less combustible
matter in proportion to the circumambient air; the quantity of light becomes increased to
eight or ten times what a long snuff would have afforded.
The light of bodies burning with flame, exists previously either combined with the
combustible body, or with the substance which supports the combustion. We know that light
exists in some bodies as a constituent part, since it is disengaged from them when they enter
into new combinations, but we are unable to obtain in a separate state the basis with which it
was combined.
That in many cases the light evolved by artificial means is derived from the combustible
body, is obvious, if we recollect that the colour of the light emitted during the process of
combustion varies, and that this variation usually depends not upon the medium which
supports the process of combustion, but upon the combustible body itself. Hence the colour
of the flame of certain combustibles, even of the purest kind may be tinged by the admixture
of various substances.
The flame of a common candle is far from being of an uniform colour. The lowest part is
always blue; and when the flame is sufficiently elongated, so as to be just ready to smoke, the
tip is red or brown.
As for the colours of flames that arise from coals, wood, and other usual combustibles, their
variety, which hardly amounts to a few shades of red or purple, intermixed with the bright
yellow light, seems principally to arise from the greater or less admixture of aqueous vapour,
dense smoke, or, in short, of other incombustible products which pass through the luminous
flame unburnt.
Spirit of wine burns with a blueish flame. The flame of sulphur has nearly the same tinge.
The flame of zinc is of a bright greenish white. The flame of most of the preparations of
copper, or of the substances with which they are mixed, is vivid green. Spirit of wine, mixed
with common salt, when set on fire, burns with a very unpleasant effect, as may be
experienced by looking at the spectators who are illuminated by such light. If a spoonful of
spirit of wine and a little boracic acid, or nitrate of copper be stirred together in a cup, and
then be set on fire, the flame will be beautifully green. If spirit of wine be mixed with nitrate
of strontia, it will, afterwards, on being inflamed, burn with a carmine red colour. Muriate of
lime tinges the flame of burning spirit of wine of an orange colour.[2]
Page 19
[2] See Chemical Amusement, comprising minute instructions for performing a series of striking and interesting
chemical experiments, p. 8, &c.
Before we consider the general nature of Gas-Light, it will be necessary to give a short sketch
of the theory and action of the instruments of illumination employed for supplying light,
together with some other facts connected with the artificial production and distribution of
light; such a proceeding will enable us to understand the general nature of the new system of
illumination which it is the object of this Essay to explain.
To procure light for the ordinary purposes of life, we are acquainted with no other ready
means than the process of combustion.
The rude method of illumination consists, as is sufficiently known, in successively burning
certain masses of fuel in the solid state: common fires answer this purpose in the apartments
of houses, and in some light-houses. Small fires of resinous wood, and the bituminous fossil,
called canel-coal, are in some countries applied to the same end, but the most general and
useful contrivance is that in which fat, or oil, of an animal or vegetable kind is burned by
means of a wick, and these contrivances comprehend candles and lamps.
In the lamp the combustible substance must be one of those which retain their fluidity at the
ordinary temperature of the atmosphere. The candle is formed of a material which is not
fusible but at a temperature considerably elevated.
All these substances must be rendered volatile before they can produce a flame, but for this
purpose it is sufficient to volatilize a small quantity of any of them, successively; for this
small quantity will suffice to give a useful light, and hence we must admire the simple, yet
wonderful contrivance of a common candle or lamp. These bodies contain a considerable
quantity of the combustible substance, sufficient to last several hours; they have likewise, in a
particular place, a slender piece of spongy vegetable substance, called the wick, which in fact
is the fire-place, or laboratory where the whole operation is conducted.
There are three articles which demand our attention in the lamp—the oil, the wick, and the
supply of air. It is required that the oil should be readily inflammable; the office of the wick
appears to be chiefly, if not solely, to convey the oil by capillary attraction to the place of
combustion; as the oil is decomposed into carburetted hydrogen gas and other products, other
oil succeeds, and in this way a continual current and maintenance of flame is effected.
When a candle is for the first time lighted, a degree of heat is given to the wick, sufficient
first to melt, and next to decompose the tallow surrounding its lower surface; and just in this
part the newly generated gas and vapour is, by admixture with the air, converted into a blue
flame; which, almost instantaneously encompassing the whole body of the vapour,
communicates so much heat to it, as to make it emit a yellowish white light. The tallow now
liquefied, as fast as it boils away at the top of the wick, is, by the capillary attraction of the
same wick, drawn up to supply the place of what is consumed by the cotton. The congeries of
capillary tubes, which form the wick, is black, because it is converted into coal; a
circumstance common to it with all other vegetable and animal substances, when part of the
carbon and hydrogen which enter into their composition having been acted on by
combustion, the remainder and other fixed parts are by any means whatever covered and
chemical experiments, p. 8, &c.
Before we consider the general nature of Gas-Light, it will be necessary to give a short sketch
of the theory and action of the instruments of illumination employed for supplying light,
together with some other facts connected with the artificial production and distribution of
light; such a proceeding will enable us to understand the general nature of the new system of
illumination which it is the object of this Essay to explain.
To procure light for the ordinary purposes of life, we are acquainted with no other ready
means than the process of combustion.
The rude method of illumination consists, as is sufficiently known, in successively burning
certain masses of fuel in the solid state: common fires answer this purpose in the apartments
of houses, and in some light-houses. Small fires of resinous wood, and the bituminous fossil,
called canel-coal, are in some countries applied to the same end, but the most general and
useful contrivance is that in which fat, or oil, of an animal or vegetable kind is burned by
means of a wick, and these contrivances comprehend candles and lamps.
In the lamp the combustible substance must be one of those which retain their fluidity at the
ordinary temperature of the atmosphere. The candle is formed of a material which is not
fusible but at a temperature considerably elevated.
All these substances must be rendered volatile before they can produce a flame, but for this
purpose it is sufficient to volatilize a small quantity of any of them, successively; for this
small quantity will suffice to give a useful light, and hence we must admire the simple, yet
wonderful contrivance of a common candle or lamp. These bodies contain a considerable
quantity of the combustible substance, sufficient to last several hours; they have likewise, in a
particular place, a slender piece of spongy vegetable substance, called the wick, which in fact
is the fire-place, or laboratory where the whole operation is conducted.
There are three articles which demand our attention in the lamp—the oil, the wick, and the
supply of air. It is required that the oil should be readily inflammable; the office of the wick
appears to be chiefly, if not solely, to convey the oil by capillary attraction to the place of
combustion; as the oil is decomposed into carburetted hydrogen gas and other products, other
oil succeeds, and in this way a continual current and maintenance of flame is effected.
When a candle is for the first time lighted, a degree of heat is given to the wick, sufficient
first to melt, and next to decompose the tallow surrounding its lower surface; and just in this
part the newly generated gas and vapour is, by admixture with the air, converted into a blue
flame; which, almost instantaneously encompassing the whole body of the vapour,
communicates so much heat to it, as to make it emit a yellowish white light. The tallow now
liquefied, as fast as it boils away at the top of the wick, is, by the capillary attraction of the
same wick, drawn up to supply the place of what is consumed by the cotton. The congeries of
capillary tubes, which form the wick, is black, because it is converted into coal; a
circumstance common to it with all other vegetable and animal substances, when part of the
carbon and hydrogen which enter into their composition having been acted on by
combustion, the remainder and other fixed parts are by any means whatever covered and
Page 20
defended from the action of the air. In this case, the burning substance owes its protection to
the surrounding flame. For when the wick, by the continual wasting of the tallow, becomes
too long to support itself in a perpendicular situation, the top of it projects out of the cone
formed by the flame, and thus being exposed to the action of the air, is ignited, loses its
blackness, and is converted into ashes; but that part of the combustible which is successively
rendered volatile by the heat of the flame is not all burnt, but part of it escapes in the form of
smoke through the middle of the flame, because that part cannot come in contact with the
oxygen of the surrounding atmosphere; hence it follows, that with a large wick and a large
flame, this waste of combustible matter is proportionately much greater than with a small
wick and a small flame. In fact, when the wick is not greater than a single thread of cotton,
the flame, though very small, is, however, peculiarly bright, and free from smoke; whereas in
lamps, with very large wicks, such as are often suspended before butchers’ shops, or with
those of the lamp-lighters, the smoke is very offensive, and in great measure eclipses the light
of the flame.
A candle differs from a lamp in one very essential circumstance; viz. that the oil or tallow is
liquefied, only as it comes into the vicinity of the combustion; and this fluid is retained in the
hollow of the part, which is still concrete, and forms a kind of cup. The wick, therefore,
should not, on this account, be too thin, because if this were the case, it would not carry off
the material as fast as it becomes fused; and the consequence would be, that it would gutter
or run down the sides of the candle: and as this inconvenience arises from the fusibility of the
tallow it is plain that a more fusible candle will require a larger wick; or that the wick of a
wax candle may be made thinner than that of one of tallow. The flame of a tallow candle will
of course be yellow, smoky, and obscure, except for a short time after snuffing. When a
candle with a thick wick is first lighted, and the wick snuffed short, the flame is perfect and
luminous, unless its diameter be very great; in which last case, there is an opake part in the
middle, where the combustion is impeded for want of air. As the wick becomes longer, the
interval between its upper extremity and the apex of the flame is diminished; and
consequently the tallow which issues from that extremity, having a less space of ignition to
pass through, is less completely burned, and passes off partly in smoke. This evil increases,
until at length the upper extremity of the wick projects beyond the flame and forms a support
for an accumulation of soot which is afforded by the imperfect combustion, and which retains
its figure, until, by the descent of the flame, the external air can have access to the upper
extremity; but in this case, the requisite combustion which might snuff it, is not effected; for
the portion of tallow emitted by the long wick is not only too large to be perfectly burned, but
also carries off much of the heat of the flame, while it assumes the elastic state. By this
diminished combustion, and increased afflux of half decomposed oil, a portion of coal or soot
is deposited on the upper part of the wick, which gradually accumulates, and at length
assumes the appearance of a fungus. The candle then does not give more than one-tenth of
the light which the due combustion of its materials would produce; and, on this account,
tallow candles require continual snuffing. But if we direct our attention to a wax candle, we
find that as its wick lengthens, the light indeed becomes less. The wick, however, being thin
and flexible, does not long occupy its place in the centre of the flame; neither does it, even in
that situation, enlarge the diameter of the flame, so as to prevent the access of air to its
internal part. When its length is too great for the vertical position, it bends on one side; and
its extremity, coming in contact with air, is burned to ashes; excepting such a portion as is
the surrounding flame. For when the wick, by the continual wasting of the tallow, becomes
too long to support itself in a perpendicular situation, the top of it projects out of the cone
formed by the flame, and thus being exposed to the action of the air, is ignited, loses its
blackness, and is converted into ashes; but that part of the combustible which is successively
rendered volatile by the heat of the flame is not all burnt, but part of it escapes in the form of
smoke through the middle of the flame, because that part cannot come in contact with the
oxygen of the surrounding atmosphere; hence it follows, that with a large wick and a large
flame, this waste of combustible matter is proportionately much greater than with a small
wick and a small flame. In fact, when the wick is not greater than a single thread of cotton,
the flame, though very small, is, however, peculiarly bright, and free from smoke; whereas in
lamps, with very large wicks, such as are often suspended before butchers’ shops, or with
those of the lamp-lighters, the smoke is very offensive, and in great measure eclipses the light
of the flame.
A candle differs from a lamp in one very essential circumstance; viz. that the oil or tallow is
liquefied, only as it comes into the vicinity of the combustion; and this fluid is retained in the
hollow of the part, which is still concrete, and forms a kind of cup. The wick, therefore,
should not, on this account, be too thin, because if this were the case, it would not carry off
the material as fast as it becomes fused; and the consequence would be, that it would gutter
or run down the sides of the candle: and as this inconvenience arises from the fusibility of the
tallow it is plain that a more fusible candle will require a larger wick; or that the wick of a
wax candle may be made thinner than that of one of tallow. The flame of a tallow candle will
of course be yellow, smoky, and obscure, except for a short time after snuffing. When a
candle with a thick wick is first lighted, and the wick snuffed short, the flame is perfect and
luminous, unless its diameter be very great; in which last case, there is an opake part in the
middle, where the combustion is impeded for want of air. As the wick becomes longer, the
interval between its upper extremity and the apex of the flame is diminished; and
consequently the tallow which issues from that extremity, having a less space of ignition to
pass through, is less completely burned, and passes off partly in smoke. This evil increases,
until at length the upper extremity of the wick projects beyond the flame and forms a support
for an accumulation of soot which is afforded by the imperfect combustion, and which retains
its figure, until, by the descent of the flame, the external air can have access to the upper
extremity; but in this case, the requisite combustion which might snuff it, is not effected; for
the portion of tallow emitted by the long wick is not only too large to be perfectly burned, but
also carries off much of the heat of the flame, while it assumes the elastic state. By this
diminished combustion, and increased afflux of half decomposed oil, a portion of coal or soot
is deposited on the upper part of the wick, which gradually accumulates, and at length
assumes the appearance of a fungus. The candle then does not give more than one-tenth of
the light which the due combustion of its materials would produce; and, on this account,
tallow candles require continual snuffing. But if we direct our attention to a wax candle, we
find that as its wick lengthens, the light indeed becomes less. The wick, however, being thin
and flexible, does not long occupy its place in the centre of the flame; neither does it, even in
that situation, enlarge the diameter of the flame, so as to prevent the access of air to its
internal part. When its length is too great for the vertical position, it bends on one side; and
its extremity, coming in contact with air, is burned to ashes; excepting such a portion as is
Page 21
defended by the continual afflux of melted wax, which is volatilized, and completely burned,
by the surrounding flame. Hence it appears, that the difficult fusibility of wax renders it
practicable to burn a large quantity of fluid by means of a small wick, and that this small
wick, by turning on one side in consequence of its flexibility, performs the operation of
snuffing itself, in a much more accurate manner than can ever be performed mechanically.
From the above statement it appears, that the important object to society of rendering tallow
candles equal to those of wax, does not at all depend on the combustibility of the respective
materials, but upon a mechanical advantage in the cup, which is afforded by the inferior
degree of fusibility in the wax: and that, in order to obtain this valuable object, one of the
following effects must be produced: either the tallow must be burned in a lamp, to avoid the
gradual progression of the flame along the wick; or some means must be devised to enable
the candle to snuff itself, as the wax-candle does; or the tallow itself must be rendered less
fusible by some chemical process. The object is, in a commercial point of view, entitled to
assiduous and extensive investigation. Chemists in general suppose the hardness or less
fusibility of wax to arise from oxygen. Mr. Nicholson[3] is led by various considerations to
imagine, that the spontaneous snuffing of candles made of tallow or other fusible materials,
will scarcely be effected but by the discovery of some material for the wick, which shall be
voluminous enough to absorb the tallow, and at the same time sufficiently flexible to bend on
one side.
[3] Philosophical Journal, 4to Series, Vol. I. p. 70.
METHOD
OF
ASCERTAINING THE ILLUMINATING POWER
OF
CANDLES, LAMPS, GAS-LIGHTS,
AND
OTHER LUMINOUS BODIES.
Though the eye is not fitted to judge of the proportional force of different lights, it can
distinguish, in many cases with great precision, when two similar surfaces, presented
together, are equally illuminated. But as the lucid particles are darted in right lines, they must
spread uniformly, and hence their density will diminish in the duplicate ratio of their
distance. From the respective situations, therefore, of the centres of divergency, when the
contrasted surfaces become equally bright, we may easily compute their relative degrees of
intensity.
For this purpose it is assumed as a principle, that the same quantity of light, diverging in all
directions from a luminous body, remains undiminished in all distances from the centre of
divergency. Thus we must suppose, that the quantity of light falling on every body, is the
same as would have fallen on the places occupied by the shadow; and if there were any doubt
of the truth of the supposition, it might be confirmed by some simple experiment. Therefore,
by the surrounding flame. Hence it appears, that the difficult fusibility of wax renders it
practicable to burn a large quantity of fluid by means of a small wick, and that this small
wick, by turning on one side in consequence of its flexibility, performs the operation of
snuffing itself, in a much more accurate manner than can ever be performed mechanically.
From the above statement it appears, that the important object to society of rendering tallow
candles equal to those of wax, does not at all depend on the combustibility of the respective
materials, but upon a mechanical advantage in the cup, which is afforded by the inferior
degree of fusibility in the wax: and that, in order to obtain this valuable object, one of the
following effects must be produced: either the tallow must be burned in a lamp, to avoid the
gradual progression of the flame along the wick; or some means must be devised to enable
the candle to snuff itself, as the wax-candle does; or the tallow itself must be rendered less
fusible by some chemical process. The object is, in a commercial point of view, entitled to
assiduous and extensive investigation. Chemists in general suppose the hardness or less
fusibility of wax to arise from oxygen. Mr. Nicholson[3] is led by various considerations to
imagine, that the spontaneous snuffing of candles made of tallow or other fusible materials,
will scarcely be effected but by the discovery of some material for the wick, which shall be
voluminous enough to absorb the tallow, and at the same time sufficiently flexible to bend on
one side.
[3] Philosophical Journal, 4to Series, Vol. I. p. 70.
METHOD
OF
ASCERTAINING THE ILLUMINATING POWER
OF
CANDLES, LAMPS, GAS-LIGHTS,
AND
OTHER LUMINOUS BODIES.
Though the eye is not fitted to judge of the proportional force of different lights, it can
distinguish, in many cases with great precision, when two similar surfaces, presented
together, are equally illuminated. But as the lucid particles are darted in right lines, they must
spread uniformly, and hence their density will diminish in the duplicate ratio of their
distance. From the respective situations, therefore, of the centres of divergency, when the
contrasted surfaces become equally bright, we may easily compute their relative degrees of
intensity.
For this purpose it is assumed as a principle, that the same quantity of light, diverging in all
directions from a luminous body, remains undiminished in all distances from the centre of
divergency. Thus we must suppose, that the quantity of light falling on every body, is the
same as would have fallen on the places occupied by the shadow; and if there were any doubt
of the truth of the supposition, it might be confirmed by some simple experiment. Therefore,
Page 22
it follows, that, since the shadow of a square inch of any surface occupies at twice the
distance of the surface from the luminous point the space of four square inches, the intensity
of the light diminishes as the square of the distance increases. If, consequently, we remove
two sources of light to such distances from an object that they may illuminate it in equal
degrees, we may conclude that their original intensities are inversely as the squares of the
distances.
Hence, if two lights of unequal illuminating powers shine upon the same surface at equal
obliquities, and an opake body be interposed between them and the illuminated surface, the
two shadows produced, must differ in blackness or intensity in the same degree. For the
shadow formed by intercepting the greater light, will be illuminated by the smaller light only,
and reversely the other shadow will be illuminated by the greater light: that is to say, the
stronger light will be attended with the deeper shadow. Now it is easy, by removing the
stronger light to a greater distance, to render the shadow which it produces at the common
surface equal to that afforded by the less. Experiments of this kind may be conveniently made
by fastening a sheet of white paper against the wall of a room; the two lights, of whatever
nature they are, intended to be compared, must then be placed so that the ray of light from
each shall fall with nearly the same angle of incidence upon the middle of the paper. In this
situation, if a book or other object be held to intercept part of the light which would have
fallen on the paper, the two shadows may be made to appear as in this figure;
where A represents the surface illuminated by one of the lights only; B, the surface
illuminated by the other light; C, the perfect shadow from which both lights are excluded. It
will easily be understood that the lights about D and E, near the angle F, will fall with equal
incidences when the double shadow is made to occupy the middle of the paper; and
consequently, if one or both of the lights be removed directly towards or from the paper, as
the appearances may require, until the two shadows at E and D have the same intensity, the
quantities of light emitted by each will be as the squares of the distances from the paper. By
some experiments made in this way, the degree of illumination of different lights may readily
be ascertained to the tenth part of the whole. And, by experiments of this kind, many useful
particulars may be shewn. For, since the cost and duration of candles, and the consumption of
oil in lamps, are easily ascertainable, it may be shewn whether more or less light is obtained
at the same expence during a given time, by burning a number of small candles instead of
one or more of greater thickness. It will therefore be easy to compare the power of different
kinds of lamps or candles, or gas lights, so as to determine the relative cost of each particular
kind of the combustible substance employed for furnishing light:—for example, if a candle
and a gas-burner supplying coal-gas, adjusted by a stop-cock, produce the same darkness of
shadow, at the same distance from the wall, the strength or intensity of light is the same. An
distance of the surface from the luminous point the space of four square inches, the intensity
of the light diminishes as the square of the distance increases. If, consequently, we remove
two sources of light to such distances from an object that they may illuminate it in equal
degrees, we may conclude that their original intensities are inversely as the squares of the
distances.
Hence, if two lights of unequal illuminating powers shine upon the same surface at equal
obliquities, and an opake body be interposed between them and the illuminated surface, the
two shadows produced, must differ in blackness or intensity in the same degree. For the
shadow formed by intercepting the greater light, will be illuminated by the smaller light only,
and reversely the other shadow will be illuminated by the greater light: that is to say, the
stronger light will be attended with the deeper shadow. Now it is easy, by removing the
stronger light to a greater distance, to render the shadow which it produces at the common
surface equal to that afforded by the less. Experiments of this kind may be conveniently made
by fastening a sheet of white paper against the wall of a room; the two lights, of whatever
nature they are, intended to be compared, must then be placed so that the ray of light from
each shall fall with nearly the same angle of incidence upon the middle of the paper. In this
situation, if a book or other object be held to intercept part of the light which would have
fallen on the paper, the two shadows may be made to appear as in this figure;
where A represents the surface illuminated by one of the lights only; B, the surface
illuminated by the other light; C, the perfect shadow from which both lights are excluded. It
will easily be understood that the lights about D and E, near the angle F, will fall with equal
incidences when the double shadow is made to occupy the middle of the paper; and
consequently, if one or both of the lights be removed directly towards or from the paper, as
the appearances may require, until the two shadows at E and D have the same intensity, the
quantities of light emitted by each will be as the squares of the distances from the paper. By
some experiments made in this way, the degree of illumination of different lights may readily
be ascertained to the tenth part of the whole. And, by experiments of this kind, many useful
particulars may be shewn. For, since the cost and duration of candles, and the consumption of
oil in lamps, are easily ascertainable, it may be shewn whether more or less light is obtained
at the same expence during a given time, by burning a number of small candles instead of
one or more of greater thickness. It will therefore be easy to compare the power of different
kinds of lamps or candles, or gas lights, so as to determine the relative cost of each particular
kind of the combustible substance employed for furnishing light:—for example, if a candle
and a gas-burner supplying coal-gas, adjusted by a stop-cock, produce the same darkness of
shadow, at the same distance from the wall, the strength or intensity of light is the same. An
Page 23
uniform degree of intensity of the gas-light may readily be produced, by opening or shutting
the stop-cock, if more or less be required, and the candle is carefully snuffed to produce the
most regular and greatest quantity of light. The size of the flame in experiments of this kind
of course becomes unnecessary, and will vary very much with the quality of the coal gas. The
bulk of the gas consumed, and the quantity of tallow used, by weighing the candle before and
after the experiment, furnish the data for ascertaining the relative costs of tallow and gas-
light, when compared with each other.
From experiments made by Count Rumford, concerning the quantity of materials requisite
for producing a light of a certain intensity for a given time: it was found that we must burn of
wax 100, of tallow 101, of oil, in an Argand’s lamp, 129, of an ill-snuffed tallow candle 229
parts, by weight. And with regard to the quantity of carburetted hydrogen, or coal-gas, I have
found that from 18 to 20 cubic feet (according to the purity of the gas) are required to give a
light equal in duration and in illuminating powers to 1lb. of tallow candles, six to the pound,
provided they were set up and burnt out one after another.[4]
[4] 112lbs. of Newcastle coal, called Tanfield Moor, produce, upon an average, from 250 to 300 cubic feet of
gas, fit for illumination.
FURTHER ILLUSTRATIONS
OF THE
MODE OF COMPUTING THE RELATIVE COST OR VALUE
OF
LIGHT,
EMITTED BY MEANS OF
CANDLES, LAMPS, & OTHER BODIES.
It is sufficiently known that the light of a candle, which is so exceedingly brilliant when first
snuffed, is very speedily diminished to one-half and is usually not more than one-fifth or one-
sixth before the uneasiness of the eye induces us to snuff it.[5] Whence it follows, that if
candles could be made so as not to require snuffing, the average quantity of light afforded by
the same quantity of combustible matter would be more than doubled.
[5] Ezekiel Walker.—Nicholson’s Journal, Vol. IV. 8vo. Series.
When a lighted candle is so placed as neither to require snuffing or produce smoke, it is
reasonable to conclude that the whole of the combustible matter which is consumed is
converted to the purpose of generating light; and that the intensities of light afforded in a
given time, by candles of different dimensions, are in proportion to the quantity of matter
consumed. That is to say; when candles are made of the same materials, if one candle
produce twice as much light as another, the former will in the same time lose twice as much
weight as the latter.
To prove the truth of this position, Mr. Walker made the experiments contained in the
following
TABLE.
the stop-cock, if more or less be required, and the candle is carefully snuffed to produce the
most regular and greatest quantity of light. The size of the flame in experiments of this kind
of course becomes unnecessary, and will vary very much with the quality of the coal gas. The
bulk of the gas consumed, and the quantity of tallow used, by weighing the candle before and
after the experiment, furnish the data for ascertaining the relative costs of tallow and gas-
light, when compared with each other.
From experiments made by Count Rumford, concerning the quantity of materials requisite
for producing a light of a certain intensity for a given time: it was found that we must burn of
wax 100, of tallow 101, of oil, in an Argand’s lamp, 129, of an ill-snuffed tallow candle 229
parts, by weight. And with regard to the quantity of carburetted hydrogen, or coal-gas, I have
found that from 18 to 20 cubic feet (according to the purity of the gas) are required to give a
light equal in duration and in illuminating powers to 1lb. of tallow candles, six to the pound,
provided they were set up and burnt out one after another.[4]
[4] 112lbs. of Newcastle coal, called Tanfield Moor, produce, upon an average, from 250 to 300 cubic feet of
gas, fit for illumination.
FURTHER ILLUSTRATIONS
OF THE
MODE OF COMPUTING THE RELATIVE COST OR VALUE
OF
LIGHT,
EMITTED BY MEANS OF
CANDLES, LAMPS, & OTHER BODIES.
It is sufficiently known that the light of a candle, which is so exceedingly brilliant when first
snuffed, is very speedily diminished to one-half and is usually not more than one-fifth or one-
sixth before the uneasiness of the eye induces us to snuff it.[5] Whence it follows, that if
candles could be made so as not to require snuffing, the average quantity of light afforded by
the same quantity of combustible matter would be more than doubled.
[5] Ezekiel Walker.—Nicholson’s Journal, Vol. IV. 8vo. Series.
When a lighted candle is so placed as neither to require snuffing or produce smoke, it is
reasonable to conclude that the whole of the combustible matter which is consumed is
converted to the purpose of generating light; and that the intensities of light afforded in a
given time, by candles of different dimensions, are in proportion to the quantity of matter
consumed. That is to say; when candles are made of the same materials, if one candle
produce twice as much light as another, the former will in the same time lose twice as much
weight as the latter.
To prove the truth of this position, Mr. Walker made the experiments contained in the
following
TABLE.
Page 24
Weight
Distance
No. of of the
of the
the No. of the Time of Candles Strength
Candles
Experi- Candles. burning. consumed of Light.
from the
ment. in a given
Wall.
time.
h. oz. dr. Feet.
1 3 0 0 15 1 7
1 - 3 3 0 1 11⁄2 1 + 7
Mould 3 0 0 15 1 7
1 2 55 0 15 1 8
2 - 3 2 55 1 0 1 + 8
Mould 2 55 0 15 1 8
1 3 0 0 153⁄4 1 8
3 - 3 3 0 1 2 11⁄8 83⁄4
Mould 3 0 0 0 1 9
5 3 0 1 5 1.18 83⁄4
4 -
Mould 3 0 1 11⁄8 1. 8
These experiments, Mr. Walker informs us, were made in the following manner:—
Three candles, the dimensions of which are given in the table, against 1, 3, and mould. These
were first weighed, and then lighted at the same instant. At the end of the time inserted in the
third column of the above table, they were extinguished and weighed again, and the loss of
weight of each candle is contained in the fourth column.
The three first experiments were made under such favourable circumstance, that there was
little doubt of their results being more accurate than what practical utility requires, but the
fourth experiment cannot be depended on so much, in consequence of the variable light of
No. 5. This candle was moved so often to keep the two shadows equal, that it was found
necessary to set down its mean distance from the wall by estimation; but as this was done
before the candles were weighed, the experimenter’s mind could not be under the influence
of partiality for a system.
The method which Mr. Walker employed in comparing one light with another in each
experiment, was that which has been described page 24.
Distance
No. of of the
of the
the No. of the Time of Candles Strength
Candles
Experi- Candles. burning. consumed of Light.
from the
ment. in a given
Wall.
time.
h. oz. dr. Feet.
1 3 0 0 15 1 7
1 - 3 3 0 1 11⁄2 1 + 7
Mould 3 0 0 15 1 7
1 2 55 0 15 1 8
2 - 3 2 55 1 0 1 + 8
Mould 2 55 0 15 1 8
1 3 0 0 153⁄4 1 8
3 - 3 3 0 1 2 11⁄8 83⁄4
Mould 3 0 0 0 1 9
5 3 0 1 5 1.18 83⁄4
4 -
Mould 3 0 1 11⁄8 1. 8
These experiments, Mr. Walker informs us, were made in the following manner:—
Three candles, the dimensions of which are given in the table, against 1, 3, and mould. These
were first weighed, and then lighted at the same instant. At the end of the time inserted in the
third column of the above table, they were extinguished and weighed again, and the loss of
weight of each candle is contained in the fourth column.
The three first experiments were made under such favourable circumstance, that there was
little doubt of their results being more accurate than what practical utility requires, but the
fourth experiment cannot be depended on so much, in consequence of the variable light of
No. 5. This candle was moved so often to keep the two shadows equal, that it was found
necessary to set down its mean distance from the wall by estimation; but as this was done
before the candles were weighed, the experimenter’s mind could not be under the influence
of partiality for a system.
The method which Mr. Walker employed in comparing one light with another in each
experiment, was that which has been described page 24.
Page 25
1. The experiments were made at different times, and the light of the mould candle was made
the standard, with which the lights of the others were compared; but it must not be
understood, that this candle gave the same strength of light in every experiment.
2. The sign + in the 5th column, signifies that the candle against which it is placed, gave a
stronger light than the others.
From the experiments contained in the table, it appears to be an established law, where
combustion is complete, that the quantities of light produced by tallow candles, are in the
complicate ratio of their times of burning and weights of matter consumed.
For if their quantities of matter be equal, and times of burning the same, they will give equal
quantities of light, by the experiments.
And if the times of burning be equal, the quantities of light will be directly as their weights of
matter expended.
Therefore the light is universally in the compound ratio of the time of burning and weight of
matter consumed.
If the law which Mr. Walker has endeavoured to prove, both by reason and experiment, be
admitted, we have a standard with which we may compare the strength of any other light.
Let a small mould candle, when lighted, be so placed as neither to produce smoke nor require
snuffing, and it will lose an ounce of its weight in three hours. Let this quantity of light
produced under these circumstances, be represented by 1.00.
Then should this candle at any other time, lose more or less of its weight in three hours than
an ounce, the quantity of light will be still known, because the quantity of light in a given
time is directly as the weight of the candle consumed.[6]
[6] To investigate rules for this purpose, 1. Let M represent the mould candle, a its distance from the wall, on
which the shadows were compared, x its quantity of matter consumed in a given time, (t) and Q the quantity of
light emitted by M in the same time: 2. Let m represent any other candle, b its distance from the same wall, and
y its quantity of matter consumed, in the time t.
Then as the intensities of light are directly as the squares of the distances of the two candles from the wall, we
b2 + Q
have as a2 : Q ∷ b2 : = the quantity of light, emitted by m in the time.
a2
Then let us suppose that the quantities of light are directly as the quantities of matter consumed in the time t,
y+Q
and we have, As x : Q ∷ y : = the quantity of light emitted by m in that time, by hypothesis.
x
b2 + Q Y+Q
Now, when (Theo. 1.) is = (Theo. 2.) the quantities of light of M and m are directly as their
a 2 X
quantities of matter consumed in any given time.
METHOD
OF INCREASING
THE LIGHT OF TALLOW CANDLES,
the standard, with which the lights of the others were compared; but it must not be
understood, that this candle gave the same strength of light in every experiment.
2. The sign + in the 5th column, signifies that the candle against which it is placed, gave a
stronger light than the others.
From the experiments contained in the table, it appears to be an established law, where
combustion is complete, that the quantities of light produced by tallow candles, are in the
complicate ratio of their times of burning and weights of matter consumed.
For if their quantities of matter be equal, and times of burning the same, they will give equal
quantities of light, by the experiments.
And if the times of burning be equal, the quantities of light will be directly as their weights of
matter expended.
Therefore the light is universally in the compound ratio of the time of burning and weight of
matter consumed.
If the law which Mr. Walker has endeavoured to prove, both by reason and experiment, be
admitted, we have a standard with which we may compare the strength of any other light.
Let a small mould candle, when lighted, be so placed as neither to produce smoke nor require
snuffing, and it will lose an ounce of its weight in three hours. Let this quantity of light
produced under these circumstances, be represented by 1.00.
Then should this candle at any other time, lose more or less of its weight in three hours than
an ounce, the quantity of light will be still known, because the quantity of light in a given
time is directly as the weight of the candle consumed.[6]
[6] To investigate rules for this purpose, 1. Let M represent the mould candle, a its distance from the wall, on
which the shadows were compared, x its quantity of matter consumed in a given time, (t) and Q the quantity of
light emitted by M in the same time: 2. Let m represent any other candle, b its distance from the same wall, and
y its quantity of matter consumed, in the time t.
Then as the intensities of light are directly as the squares of the distances of the two candles from the wall, we
b2 + Q
have as a2 : Q ∷ b2 : = the quantity of light, emitted by m in the time.
a2
Then let us suppose that the quantities of light are directly as the quantities of matter consumed in the time t,
y+Q
and we have, As x : Q ∷ y : = the quantity of light emitted by m in that time, by hypothesis.
x
b2 + Q Y+Q
Now, when (Theo. 1.) is = (Theo. 2.) the quantities of light of M and m are directly as their
a 2 X
quantities of matter consumed in any given time.
METHOD
OF INCREASING
THE LIGHT OF TALLOW CANDLES,
Page 26
AND TO OBVIATE THE
NECESSITY OF SNUFFING THEM.
Mr. Ezekiel Walker has shewn that, if a trifling alteration be made in the method of using
common tallow candles, they will become excellent substitutes for those of wax.
A common candle, weighing one-tenth of a pound, containing fourteen single threads of fine
cotton, placed so as to form an angle of 30 degrees[7] with the perpendicular, and lighted,
requires no snuffing; and what is much more valuable for some purposes, it gives a light that
is nearly uniform in strength without the least smoke. These effects are thus produced:
[7] Candlesticks may be made to hold the candle at this angle, or they may be so contrived as to hold the candle
at any angle at pleasure.
When a candle burns in an inclined position, most part of the flame rises perpendicularly
from the upper side of the wick, and when viewed in a certain direction, it appears in the
form of an obtuse angled triangle. And as the end of the wick projects beyond the flame at the
obtuse angle, it meets with the air, and is completely burnt to ashes: hence it is rendered
incapable of acting as a conductor to carry off part of the combustible matter in the form of
smoke. By this spontaneous mode of snuffing, that part of the wick which is acted upon by
the flame continues of the same length, and the flame itself very nearly of the same strength
and magnitude[8].
[8] The wick’s not being uniformly twisted throughout, may occasion a little variation in the dimensions of the
flame.
The advantages which may be derived from candles that require no snuffing and afford no
smoke, may be readily understood; but these candles have another property which ought not
to be passed over in silence. A candle snuffed by an instrument gives a very fluctuating light,
which, in viewing near objects is highly injurious to the eye; and this is an inconvenience
which no shade can remove. But when a candle is snuffed spontaneously, it gives a light so
perfectly steady and so uniformly bright, that the adjustments of the eye remain at rest, and
distinct vision is performed without pain, and without uneasiness.
Candles, on which Mr. Walker has made experiments, are described in the following
TABLE.
No. of
No. of
candles
single
to the Length
threads
No. pound in
of fine
avoir- inches.
cotton
dupoise
in the wick.
weight.
1 14 8.5 10
2 13 9. 12
3 10 9.74 14
NECESSITY OF SNUFFING THEM.
Mr. Ezekiel Walker has shewn that, if a trifling alteration be made in the method of using
common tallow candles, they will become excellent substitutes for those of wax.
A common candle, weighing one-tenth of a pound, containing fourteen single threads of fine
cotton, placed so as to form an angle of 30 degrees[7] with the perpendicular, and lighted,
requires no snuffing; and what is much more valuable for some purposes, it gives a light that
is nearly uniform in strength without the least smoke. These effects are thus produced:
[7] Candlesticks may be made to hold the candle at this angle, or they may be so contrived as to hold the candle
at any angle at pleasure.
When a candle burns in an inclined position, most part of the flame rises perpendicularly
from the upper side of the wick, and when viewed in a certain direction, it appears in the
form of an obtuse angled triangle. And as the end of the wick projects beyond the flame at the
obtuse angle, it meets with the air, and is completely burnt to ashes: hence it is rendered
incapable of acting as a conductor to carry off part of the combustible matter in the form of
smoke. By this spontaneous mode of snuffing, that part of the wick which is acted upon by
the flame continues of the same length, and the flame itself very nearly of the same strength
and magnitude[8].
[8] The wick’s not being uniformly twisted throughout, may occasion a little variation in the dimensions of the
flame.
The advantages which may be derived from candles that require no snuffing and afford no
smoke, may be readily understood; but these candles have another property which ought not
to be passed over in silence. A candle snuffed by an instrument gives a very fluctuating light,
which, in viewing near objects is highly injurious to the eye; and this is an inconvenience
which no shade can remove. But when a candle is snuffed spontaneously, it gives a light so
perfectly steady and so uniformly bright, that the adjustments of the eye remain at rest, and
distinct vision is performed without pain, and without uneasiness.
Candles, on which Mr. Walker has made experiments, are described in the following
TABLE.
No. of
No. of
candles
single
to the Length
threads
No. pound in
of fine
avoir- inches.
cotton
dupoise
in the wick.
weight.
1 14 8.5 10
2 13 9. 12
3 10 9.74 14
Page 27
4 8 10. 20
5 6 10.25 24
Mould 6 13.
Number 1, 2, and 3. These candles, when lighted and placed to form an angle of 30° with the
perpendicular, require no snuffing: they give lights which are nearly equal, and combustion
proceeds so regularly, that no part of the melted tallow escapes unconsumed, except from
accidental causes.
No. 4, placed at the angle mentioned above, and lighted, requires no snuffing: it gives a light
very little stronger than No. 1, but its colour is not quite so white, nor its flame so steady.
No. 5. This candle, placed at an angle of 30°, and lighted, requires no snuffing; its flame is
rather fluctuating, and not so white as No. 4, nor is its strength of light much greater than No.
1. The melted tallow sometimes overflows when the air in the room is put in motion; yet the
light of this candle is much improved by being placed in an inclined position.
The mould candle, treated in the same manner, affords a very pure steady flame, without
smoke and without snuffing, and its strength of light is about equal to that of No. 1.
The experiments have not been sufficiently numerous to determine with precision which of
these candles affords the most light at a given expence, but the few experiments which have
been made seem to indicate, that the quantity of light is nearly as the quantity of combustible
matter consumed, and thus a candle which is used in the manner pointed out gives more light
than a candle of the same dimension set perpendicularly and snuffed, because one part of a
candle that is snuffed, is thrown away, and another part flies off in the form of smoke. And
this is not the only inconvenience that attends the using candles in this manner, and which the
other method is free from, for the light which it gives is of a bad quality, on account of its
being variable and undulating.
From the time that a candle is snuffed till it wants snuffing again, its strength of light scarcely
continues the same for a single minute. And that variation which frequently takes place in the
height of the flame, is a matter of still more serious consequence.
The flame of a long candle placed vertically when it is snuffed burns steadily, is about two
inches high, but it very frequently rises to the height of four inches or upwards; drops down
again in a moment, till it is less than three inches, and then rises again. In this manner the
flame continues in motion for some time before it returns to its original dimensions. But it
does not continue long in a quiescent state before it begins a new series of undulations. In
this manner the candle burns till the top of the wick is seen near the apex of the flame,
carrying off clouds of smoke. In this state of things the eye becomes uneasy for want of light,
and the snuffers are applied to remove the inconvenience.
Mr. Walker further observes, that it is these sudden changes, and not the nature of candle-
light itself, that do so much injury to the eye of the student and artist; and that that injury may
be easily prevented, by laying aside the snuffers, and in the place of one large candle, let two
small ones be used in the manner stated.
5 6 10.25 24
Mould 6 13.
Number 1, 2, and 3. These candles, when lighted and placed to form an angle of 30° with the
perpendicular, require no snuffing: they give lights which are nearly equal, and combustion
proceeds so regularly, that no part of the melted tallow escapes unconsumed, except from
accidental causes.
No. 4, placed at the angle mentioned above, and lighted, requires no snuffing: it gives a light
very little stronger than No. 1, but its colour is not quite so white, nor its flame so steady.
No. 5. This candle, placed at an angle of 30°, and lighted, requires no snuffing; its flame is
rather fluctuating, and not so white as No. 4, nor is its strength of light much greater than No.
1. The melted tallow sometimes overflows when the air in the room is put in motion; yet the
light of this candle is much improved by being placed in an inclined position.
The mould candle, treated in the same manner, affords a very pure steady flame, without
smoke and without snuffing, and its strength of light is about equal to that of No. 1.
The experiments have not been sufficiently numerous to determine with precision which of
these candles affords the most light at a given expence, but the few experiments which have
been made seem to indicate, that the quantity of light is nearly as the quantity of combustible
matter consumed, and thus a candle which is used in the manner pointed out gives more light
than a candle of the same dimension set perpendicularly and snuffed, because one part of a
candle that is snuffed, is thrown away, and another part flies off in the form of smoke. And
this is not the only inconvenience that attends the using candles in this manner, and which the
other method is free from, for the light which it gives is of a bad quality, on account of its
being variable and undulating.
From the time that a candle is snuffed till it wants snuffing again, its strength of light scarcely
continues the same for a single minute. And that variation which frequently takes place in the
height of the flame, is a matter of still more serious consequence.
The flame of a long candle placed vertically when it is snuffed burns steadily, is about two
inches high, but it very frequently rises to the height of four inches or upwards; drops down
again in a moment, till it is less than three inches, and then rises again. In this manner the
flame continues in motion for some time before it returns to its original dimensions. But it
does not continue long in a quiescent state before it begins a new series of undulations. In
this manner the candle burns till the top of the wick is seen near the apex of the flame,
carrying off clouds of smoke. In this state of things the eye becomes uneasy for want of light,
and the snuffers are applied to remove the inconvenience.
Mr. Walker further observes, that it is these sudden changes, and not the nature of candle-
light itself, that do so much injury to the eye of the student and artist; and that that injury may
be easily prevented, by laying aside the snuffers, and in the place of one large candle, let two
small ones be used in the manner stated.
Page 28
The following observations on this subject are copied from the Monthly Magazine, 1805, p.
206.
“It is scarcely necessary to observe, that the combustion of candles proceeds the quicker in
proportion as the inclination is greater. From the experiments which I have made, I should
consider an angle of forty degrees with the perpendicular as the maximum of inclination,
beyond which several considerable inconveniencies would occur; and I should take 25
degrees as the minimum of inclination, less than which does not sufficiently expose the point
of the wick to the action of the air.
“By those who are much in the habit of reading or writing by candle-light, it will also be
esteemed no inconsiderable addition to the advantages already mentioned, that the trouble of
seeking and applying the snuffers is superseded. A candle of common size in a vertical
position, requires the application of the snuffers forty-five times during its complete
consumption.
“But I found an obstacle to the adoption of Mr. Walker’s plan, which, from the inclined
position of the candle, it did not immediately occur to me by what means to counteract. Any
agitation of the air of the room, occasioned either by the opening or shutting of a door, or by
the quick passage of a person near the candle, caused the melted tallow to run over, or, in
more familiar language, caused the candle to gutter; which, with the candle in this position,
became an insuperable bar to the use of it.
“For the prevention of this inconvenience, I have had a wire skeleton-shade adapted to a rod
bearing the same inclination as the candle, and which at bottom joins the candlestick in an
horizontal line of about two inches, terminating in a nozzle fitting that of the candlestick.—
The distance of this rod from the candlestick, or, which is the same thing, the length of the
foot or horizontal line, is of course to be determined by the distance between the two circles
which form the upper and lower apertures of the shade.—It may serve, perhaps, more
familiarly to describe this part of the apparatus, to state, that it bears a perfect resemblance to
the two first strokes of the written figure 4; and the third stroke, if carried up as high as the
first, and made sloping instead of upright, will very well represent the situation of the candle.
“When a strong light, for the purposes of reading or writing, be required, a white silk or
paper may be used, as is common, over the skeleton; but when it be required that the light
should be dispersed over the room, a glass of a similar shape may be adopted, for the purpose
of preventing the flame from being influenced by any agitation of the air of the room. If the
upper circle of the shade be four inches in diameter, the apex of the flame will be within it
during more than half the time of the complete consumption of the candle; the shade will not,
therefore, require adjusting for the purpose of preventing injury to the silk, or whatever else
may be used over the skeleton, more than once during that time.
“Being myself much averse to the interruptions which a candle used in a vertical position
occasions, and which, though short, may, under some circumstances, be highly vexatious, I
wish to extend to others a benefit which I prize rather highly.”
Lord Stanhope[9] has published a simple method of manufacturing candles, which, according
to his Lordship’s statement, is superior to the method usually employed. The principles upon
206.
“It is scarcely necessary to observe, that the combustion of candles proceeds the quicker in
proportion as the inclination is greater. From the experiments which I have made, I should
consider an angle of forty degrees with the perpendicular as the maximum of inclination,
beyond which several considerable inconveniencies would occur; and I should take 25
degrees as the minimum of inclination, less than which does not sufficiently expose the point
of the wick to the action of the air.
“By those who are much in the habit of reading or writing by candle-light, it will also be
esteemed no inconsiderable addition to the advantages already mentioned, that the trouble of
seeking and applying the snuffers is superseded. A candle of common size in a vertical
position, requires the application of the snuffers forty-five times during its complete
consumption.
“But I found an obstacle to the adoption of Mr. Walker’s plan, which, from the inclined
position of the candle, it did not immediately occur to me by what means to counteract. Any
agitation of the air of the room, occasioned either by the opening or shutting of a door, or by
the quick passage of a person near the candle, caused the melted tallow to run over, or, in
more familiar language, caused the candle to gutter; which, with the candle in this position,
became an insuperable bar to the use of it.
“For the prevention of this inconvenience, I have had a wire skeleton-shade adapted to a rod
bearing the same inclination as the candle, and which at bottom joins the candlestick in an
horizontal line of about two inches, terminating in a nozzle fitting that of the candlestick.—
The distance of this rod from the candlestick, or, which is the same thing, the length of the
foot or horizontal line, is of course to be determined by the distance between the two circles
which form the upper and lower apertures of the shade.—It may serve, perhaps, more
familiarly to describe this part of the apparatus, to state, that it bears a perfect resemblance to
the two first strokes of the written figure 4; and the third stroke, if carried up as high as the
first, and made sloping instead of upright, will very well represent the situation of the candle.
“When a strong light, for the purposes of reading or writing, be required, a white silk or
paper may be used, as is common, over the skeleton; but when it be required that the light
should be dispersed over the room, a glass of a similar shape may be adopted, for the purpose
of preventing the flame from being influenced by any agitation of the air of the room. If the
upper circle of the shade be four inches in diameter, the apex of the flame will be within it
during more than half the time of the complete consumption of the candle; the shade will not,
therefore, require adjusting for the purpose of preventing injury to the silk, or whatever else
may be used over the skeleton, more than once during that time.
“Being myself much averse to the interruptions which a candle used in a vertical position
occasions, and which, though short, may, under some circumstances, be highly vexatious, I
wish to extend to others a benefit which I prize rather highly.”
Lord Stanhope[9] has published a simple method of manufacturing candles, which, according
to his Lordship’s statement, is superior to the method usually employed. The principles upon
Page 29
which the process depends are the following:—First, the wick of the candle is to have only
three-fourths of the usual number of cotton threads, if the candle be of wax or spermaceti;
and only two-thirds of the usual number, if the candle be of tallow. Secondly, it is required
that the wick in all cases be perfectly free from moisture, a circumstance seldom attended to
in the manufacturing of candles; and thirdly, to deprive the wick of wax candles, of all the air
which is entangled in its fibres, and this may conveniently be done, by boiling it in melted
wax, till no more air bubbles, or froth appear on the surface of the fluid.
[9] Repository of Arts, Vol. I, p. 86.
If these circumstances be attended to, three candles of any size thus prepared, last as long as
four of the same size manufactured in the common way. The light which they afford is
superior and more steady than the light of common candles; and lastly, candles made in this
manner, whether of wax, spermaceti, or tallow, do not require to be snuffed as often. Besides
all this, they flame much less, and are consequently better for writing, reading, working and
drawing, than candles made by the common method.
The following observations will enable any person who is willing to try the candles
manufactured according to Lord Stanhope’s plan, to ascertain the real value of the
improvements suggested by his Lordship. It shews also the result of some experiments, made
to ascertain the expence of burning oil in lamps with wicks of various sizes.
A taper lamp, with eight threads of cotton, will consume in one hour 225⁄1000 oz. of spermaceti
oil: at six shillings per gallon, the expence of burning twelve hours is 13.71 farthings.
At seven shillings, it is 15.995 farthings.
At eight shillings, it is 18.280 farthings.
N. B. This gives as good a light as tallow candles of eight and ten in the pound. This lamp
seldom wants snuffing, and casts a steady and strong light.
A taper, chamber, or watch lamp, with four ordinary threads of cotton in the wick, consumes
1.664 oz. of spermaceti oil in one hour: the oil at seven shillings per gallon, the expence of
burning twelve hours, 7.02 farthings.
At eight shillings, it is 8.022 farthings.
At nine shillings, it is 9.024 farthings.
TABLE,
Exhibiting a series of experiments, made with a view to determine the real and comparative
expence of burning candles of different sorts and sizes.
The expence in twelve hours
Number of Time The time
Weight when candles are at 12s.
candles one that
of one per dozen, which also shews
in one candle one pound
candle. the proportion of expence
pound. lasted. will last.
at any price, per dozen.
three-fourths of the usual number of cotton threads, if the candle be of wax or spermaceti;
and only two-thirds of the usual number, if the candle be of tallow. Secondly, it is required
that the wick in all cases be perfectly free from moisture, a circumstance seldom attended to
in the manufacturing of candles; and thirdly, to deprive the wick of wax candles, of all the air
which is entangled in its fibres, and this may conveniently be done, by boiling it in melted
wax, till no more air bubbles, or froth appear on the surface of the fluid.
[9] Repository of Arts, Vol. I, p. 86.
If these circumstances be attended to, three candles of any size thus prepared, last as long as
four of the same size manufactured in the common way. The light which they afford is
superior and more steady than the light of common candles; and lastly, candles made in this
manner, whether of wax, spermaceti, or tallow, do not require to be snuffed as often. Besides
all this, they flame much less, and are consequently better for writing, reading, working and
drawing, than candles made by the common method.
The following observations will enable any person who is willing to try the candles
manufactured according to Lord Stanhope’s plan, to ascertain the real value of the
improvements suggested by his Lordship. It shews also the result of some experiments, made
to ascertain the expence of burning oil in lamps with wicks of various sizes.
A taper lamp, with eight threads of cotton, will consume in one hour 225⁄1000 oz. of spermaceti
oil: at six shillings per gallon, the expence of burning twelve hours is 13.71 farthings.
At seven shillings, it is 15.995 farthings.
At eight shillings, it is 18.280 farthings.
N. B. This gives as good a light as tallow candles of eight and ten in the pound. This lamp
seldom wants snuffing, and casts a steady and strong light.
A taper, chamber, or watch lamp, with four ordinary threads of cotton in the wick, consumes
1.664 oz. of spermaceti oil in one hour: the oil at seven shillings per gallon, the expence of
burning twelve hours, 7.02 farthings.
At eight shillings, it is 8.022 farthings.
At nine shillings, it is 9.024 farthings.
TABLE,
Exhibiting a series of experiments, made with a view to determine the real and comparative
expence of burning candles of different sorts and sizes.
The expence in twelve hours
Number of Time The time
Weight when candles are at 12s.
candles one that
of one per dozen, which also shews
in one candle one pound
candle. the proportion of expence
pound. lasted. will last.
at any price, per dozen.
Page 30
Farthings and
Oz. Dr. Hr. Min. Hr. Min.
hundredth parts.
A small 183⁄4 0 14 3 15 59 26 9.70
wick. 19 0 131⁄2 2 40 50 34 11.40
A large 161⁄2 0 151⁄2 2 40 44 2 13.08
wick. 12 1 51⁄4 3 27 41 24 13.92
103⁄4 1 8 3 36 38 24 15.00
73⁄4 2 1 4 9 32 12 17.88
8 2 0 4 15 34 0 16.94
53⁄4 2 13 5 19 30 15 19.06
Mould Moulds at 14d.
candles. Each. per dozen.
With 37⁄8 2 12 7 20 42 39 15.74
wax’d 4 4 0 9 3 36 20 18.56
wick. 3 5 23⁄4 17 30 52 30 16.825
The time each candle lasted, was taken from an average of several trials on each size.
It has been suggested by Dr. Franklin, that the flame of two candles joined, gives a much
stronger light than both of them separately. The same, has been observed by Mr. Warren, to
be the case with flames of gas-lights, which, when combined, give a much stronger light than
they would afford, when in a separate state.
Indeed, in all cases, where flames for producing light are placed near to each other, it is
always beneficial to preserve the heat of the flame as much as possible. One of the most
simple methods of doing this, is no doubt, the placing of the several flames together, and as
near as possible to each other without touching, in order that they may mutually cover and
defend each other against the powerful cooling influence of the surrounding cold bodies. This
principle is now employed in the Liverpool lamp, which acts by several flat or ribband wicks
placed in the form of a cylinder. The power of illumination of this lamp is superior in effect
and more economical than any other lamp in use—and as flame is perfectly transparent to the
light of another flame which passes through it, there is no danger of loss of light on account
of the flames covering each other.
Oz. Dr. Hr. Min. Hr. Min.
hundredth parts.
A small 183⁄4 0 14 3 15 59 26 9.70
wick. 19 0 131⁄2 2 40 50 34 11.40
A large 161⁄2 0 151⁄2 2 40 44 2 13.08
wick. 12 1 51⁄4 3 27 41 24 13.92
103⁄4 1 8 3 36 38 24 15.00
73⁄4 2 1 4 9 32 12 17.88
8 2 0 4 15 34 0 16.94
53⁄4 2 13 5 19 30 15 19.06
Mould Moulds at 14d.
candles. Each. per dozen.
With 37⁄8 2 12 7 20 42 39 15.74
wax’d 4 4 0 9 3 36 20 18.56
wick. 3 5 23⁄4 17 30 52 30 16.825
The time each candle lasted, was taken from an average of several trials on each size.
It has been suggested by Dr. Franklin, that the flame of two candles joined, gives a much
stronger light than both of them separately. The same, has been observed by Mr. Warren, to
be the case with flames of gas-lights, which, when combined, give a much stronger light than
they would afford, when in a separate state.
Indeed, in all cases, where flames for producing light are placed near to each other, it is
always beneficial to preserve the heat of the flame as much as possible. One of the most
simple methods of doing this, is no doubt, the placing of the several flames together, and as
near as possible to each other without touching, in order that they may mutually cover and
defend each other against the powerful cooling influence of the surrounding cold bodies. This
principle is now employed in the Liverpool lamp, which acts by several flat or ribband wicks
placed in the form of a cylinder. The power of illumination of this lamp is superior in effect
and more economical than any other lamp in use—and as flame is perfectly transparent to the
light of another flame which passes through it, there is no danger of loss of light on account
of the flames covering each other.
Page 31
PART II.
GAS-LIGHT.
PRELIMINARY OBSERVATION.
A new art of procuring artificial light, which consists in burning the gazeous fluid obtained
by distillation from common pit-coal, has of late engaged the attention of the public, under
the name of gas-light.
The encouragement that has been given for some years past by the legislature to this system
of lighting, has induced certain individuals to apply the coal-gas light for the illumination of
streets, houses, roads, and public edifices. And it is sufficiently known that a company has
been incorporated by charter under the name of the “Gas Light and Coke Company,” to apply
this new art of procuring light, by way of experiment, on a large scale, in lighting the streets
of the metropolis.[10]
[10] An Act for granting certain powers and authorities to a company to be incorporated by charter, called the
“Gas Light and Coke Company,” for making inflammable air for the lighting of the streets of the metropolis,
&c.—Session 1810, 50th Geo. III.
The power and authorities granted to this corporate body are very restricted and moderate.
The individuals composing it have no exclusive privilege; their charter does not prevent other
persons from entering into competition with them. Their operations are confined to the
metropolis where they are bound to furnish not only a stronger and better light to such streets
and parishes as chuse to be lighted with gas, but also at a cheaper price than shall be paid for
lighting the said streets with oil in the usual manner. The corporation is not permitted to
traffic in machinery for manufacturing or conveying the gas into private houses, their capital
or joint stock is limited to 200,000l. and His Majesty has the power of declaring the gas-light
charter void, if the company fail to fulfil the terms of it.
THEORY
OF
THE COMBUSTION OF COAL
IN
ELUCIDATION OF THE NATURE AND PRODUCTION
GAS-LIGHT.
PRELIMINARY OBSERVATION.
A new art of procuring artificial light, which consists in burning the gazeous fluid obtained
by distillation from common pit-coal, has of late engaged the attention of the public, under
the name of gas-light.
The encouragement that has been given for some years past by the legislature to this system
of lighting, has induced certain individuals to apply the coal-gas light for the illumination of
streets, houses, roads, and public edifices. And it is sufficiently known that a company has
been incorporated by charter under the name of the “Gas Light and Coke Company,” to apply
this new art of procuring light, by way of experiment, on a large scale, in lighting the streets
of the metropolis.[10]
[10] An Act for granting certain powers and authorities to a company to be incorporated by charter, called the
“Gas Light and Coke Company,” for making inflammable air for the lighting of the streets of the metropolis,
&c.—Session 1810, 50th Geo. III.
The power and authorities granted to this corporate body are very restricted and moderate.
The individuals composing it have no exclusive privilege; their charter does not prevent other
persons from entering into competition with them. Their operations are confined to the
metropolis where they are bound to furnish not only a stronger and better light to such streets
and parishes as chuse to be lighted with gas, but also at a cheaper price than shall be paid for
lighting the said streets with oil in the usual manner. The corporation is not permitted to
traffic in machinery for manufacturing or conveying the gas into private houses, their capital
or joint stock is limited to 200,000l. and His Majesty has the power of declaring the gas-light
charter void, if the company fail to fulfil the terms of it.
THEORY
OF
THE COMBUSTION OF COAL
IN
ELUCIDATION OF THE NATURE AND PRODUCTION
Page 32
OF
GAS LIGHT.
Pit-coal exists in this island in strata, which, as far as concerns many hundred generations
after us, may be pronounced inexhaustible; and is so admirably adapted, both for domestic
purposes and the uses of the arts, that it is justly regarded as a most essential constituent of
our national wealth. Like all other bituminous substances, it is composed of a fixed
carbonaceous base or bitumen, united to more or less earthy and saline matter constituting the
ashes left behind when this substance is burnt. The proportions of these parts differ
considerably, in different kinds of coal; and according to the prevalency of one or other of
them, so the coal is more or less combustible, and possesses the characters of perfect pit-coal;
and by various shades, passes from the most inflammable canel-coal, into blind, Kilkenny, or
stone-coal; and, lastly, into a variety of earthy or stony substances; which, although they are
inflammable, do not merit the appellation of coal.
Every body knows that when pit-coals are burning in our grates, a flame more or less
luminous issues from them, and that they frequently emit beautiful streams of flame
remarkably bright. But besides the flame, which is a peculiar gas in the state of combustion,
heat expels from coal an aqueous vapour, loaded with several kinds of ammoniacal salts, a
thick viscid fluid resembling tar, and some gases that are not of a combustible nature. The
consequence of which is, that the flame of a coal-fire is continually wavering and changing,
both in shape, as well as brilliance and in colour, so that what one moment gave a beautiful
bright light, in the next, perhaps, is obscured by a stream of thick smoke.
But if coals, instead of being suffered to burn in this way, are submitted to distillation in close
vessels, all its immediate constituent parts may be collected. The bituminous part is melted
out in the form of tar. There is disengaged at the same time, a large quantity of an aqueous
fluid, contaminated with a portion of oil, and various ammoniacal salts. A large quantity of
carburetted hidrogen, and other uninflammable gases, make their appearance, and the fixed
base of the coal remains behind in the distillatory apparatus in the form of a carbonaceous
substance, called coke.
All these products may be separately collected in different vessels. The carburetted hidrogen,
or coal-gas, may be freed from the non-inflammable gases, and afterwards forced in streams
out of small appertures, which, when lighted, may serve as the flame of a candle to illuminate
a room or any other place. It is thus, that from pit-coal a native production of this country, we
may procure a pure, lasting, and copious light; which, in other cases, must be derived from
expensive materials, in part imported from abroad.
It is chiefly upon the power of collecting the products afforded by coal, with convenience and
cheapness, that the promoters of the gas-light illumination found their claims to public
encouragement. They conceive that the flame which pit-coal yields, as it is now consumed, is
turned to very little advantage: it is not only confined to one place, where a red heat is more
wanted than a brilliant flame, but it is obscured, and sometimes entirely smothered, by the
quantity of incombustible materials that ascend along with it and pollute the atmosphere.
GAS LIGHT.
Pit-coal exists in this island in strata, which, as far as concerns many hundred generations
after us, may be pronounced inexhaustible; and is so admirably adapted, both for domestic
purposes and the uses of the arts, that it is justly regarded as a most essential constituent of
our national wealth. Like all other bituminous substances, it is composed of a fixed
carbonaceous base or bitumen, united to more or less earthy and saline matter constituting the
ashes left behind when this substance is burnt. The proportions of these parts differ
considerably, in different kinds of coal; and according to the prevalency of one or other of
them, so the coal is more or less combustible, and possesses the characters of perfect pit-coal;
and by various shades, passes from the most inflammable canel-coal, into blind, Kilkenny, or
stone-coal; and, lastly, into a variety of earthy or stony substances; which, although they are
inflammable, do not merit the appellation of coal.
Every body knows that when pit-coals are burning in our grates, a flame more or less
luminous issues from them, and that they frequently emit beautiful streams of flame
remarkably bright. But besides the flame, which is a peculiar gas in the state of combustion,
heat expels from coal an aqueous vapour, loaded with several kinds of ammoniacal salts, a
thick viscid fluid resembling tar, and some gases that are not of a combustible nature. The
consequence of which is, that the flame of a coal-fire is continually wavering and changing,
both in shape, as well as brilliance and in colour, so that what one moment gave a beautiful
bright light, in the next, perhaps, is obscured by a stream of thick smoke.
But if coals, instead of being suffered to burn in this way, are submitted to distillation in close
vessels, all its immediate constituent parts may be collected. The bituminous part is melted
out in the form of tar. There is disengaged at the same time, a large quantity of an aqueous
fluid, contaminated with a portion of oil, and various ammoniacal salts. A large quantity of
carburetted hidrogen, and other uninflammable gases, make their appearance, and the fixed
base of the coal remains behind in the distillatory apparatus in the form of a carbonaceous
substance, called coke.
All these products may be separately collected in different vessels. The carburetted hidrogen,
or coal-gas, may be freed from the non-inflammable gases, and afterwards forced in streams
out of small appertures, which, when lighted, may serve as the flame of a candle to illuminate
a room or any other place. It is thus, that from pit-coal a native production of this country, we
may procure a pure, lasting, and copious light; which, in other cases, must be derived from
expensive materials, in part imported from abroad.
It is chiefly upon the power of collecting the products afforded by coal, with convenience and
cheapness, that the promoters of the gas-light illumination found their claims to public
encouragement. They conceive that the flame which pit-coal yields, as it is now consumed, is
turned to very little advantage: it is not only confined to one place, where a red heat is more
wanted than a brilliant flame, but it is obscured, and sometimes entirely smothered, by the
quantity of incombustible materials that ascend along with it and pollute the atmosphere.
Page 33
That much inflammable matter is thus lost, is evident from facts that come under our daily
observation. We often see a flame suddenly burst from the densest smoke, and as suddenly
disappear; and if a light be applied to the little jets that issue from the bituminous parts of the
coal, they will catch fire, and burn with a bright flame. A considerable quantity of a gazeous
fluid, capable of affording light and heat continually escapes up the chimney, whilst another
part is occasionally ignited, and exhibits the phenomena of the flame and light of the fire.
The theory of the production of gas-light is therefore analogous to the action of a lamp or
candle. The wick of a candle being surrounded by the flame, is in the same situation of the
pit-coal exposed to distillation. The office of the wick is chiefly to convey tallow, by capillary
attraction, to the place of combustion. As it is decomposed into carburetted hidrogen gas it is
consumed and flies off, another portion succeeds; and in this way a continued current of
tallow and maintenance of flame are effected. See page 15.
The combustion of oil by means of a lamp depends on similar circumstances. The tubes
formed by the wick serve the same office as a retort placed in a heated furnace through which
the inflammable liquid is transmitted. The oil is drawn up into these ignited tubes, and is
decomposed into carburetted hidrogen gas, and from the combustion of this gas the
illumination proceeds. See p. 15. What then does the gas-light system attempt? Nothing more
than to generate, by means of sufficient furnaces and a reservoir of sufficient capacity,
desired quantities of the gas, which is the same material of the flame of candles or lamps; and
then by passing it through pipes to any desired distance, to exhibit it there at the mouths of
the conducting tubes, so that it may be ignited for any desired purpose. The only difference
between this process and that of an ordinary candle or lamp, consists in having the furnace at
the manufactory, instead of its being in the wick of the candle or lamp—in having the
inflammable material distilled at the station, instead of its present exhibitions in oil, wax, or
tallow, and then in transmitting the gas to any required distance, and igniting it at the orifice
of the conducting pipe instead of igniting it at the apex of the wick. The principle is rational,
and justified by the universal mode in which all light is produced. Indeed, this discovery
ranks among the numerous recent applications of chemical science to the purposes of life,
which promise to be of the most general utility.
It is evident from the outline here given of the production and application of coal-gas, that all
the uses of pit-coal are not exhausted; it will be sufficient to observe, that the complete
analysis of coal, which has been hitherto confined to the laboratory of the chemist, requiring
skill and nicety in the operator, and attended with great trouble and expence, is now so far
simplified, that many chaldrons of coals may be decomposed by one gas-light apparatus in
the space of six hours, and all the component parts produced in their most useful shape, at an
expence out of all proportion below the value of the products.
SKETCH
OF
THE RISE AND PROGRESS
OF THE
observation. We often see a flame suddenly burst from the densest smoke, and as suddenly
disappear; and if a light be applied to the little jets that issue from the bituminous parts of the
coal, they will catch fire, and burn with a bright flame. A considerable quantity of a gazeous
fluid, capable of affording light and heat continually escapes up the chimney, whilst another
part is occasionally ignited, and exhibits the phenomena of the flame and light of the fire.
The theory of the production of gas-light is therefore analogous to the action of a lamp or
candle. The wick of a candle being surrounded by the flame, is in the same situation of the
pit-coal exposed to distillation. The office of the wick is chiefly to convey tallow, by capillary
attraction, to the place of combustion. As it is decomposed into carburetted hidrogen gas it is
consumed and flies off, another portion succeeds; and in this way a continued current of
tallow and maintenance of flame are effected. See page 15.
The combustion of oil by means of a lamp depends on similar circumstances. The tubes
formed by the wick serve the same office as a retort placed in a heated furnace through which
the inflammable liquid is transmitted. The oil is drawn up into these ignited tubes, and is
decomposed into carburetted hidrogen gas, and from the combustion of this gas the
illumination proceeds. See p. 15. What then does the gas-light system attempt? Nothing more
than to generate, by means of sufficient furnaces and a reservoir of sufficient capacity,
desired quantities of the gas, which is the same material of the flame of candles or lamps; and
then by passing it through pipes to any desired distance, to exhibit it there at the mouths of
the conducting tubes, so that it may be ignited for any desired purpose. The only difference
between this process and that of an ordinary candle or lamp, consists in having the furnace at
the manufactory, instead of its being in the wick of the candle or lamp—in having the
inflammable material distilled at the station, instead of its present exhibitions in oil, wax, or
tallow, and then in transmitting the gas to any required distance, and igniting it at the orifice
of the conducting pipe instead of igniting it at the apex of the wick. The principle is rational,
and justified by the universal mode in which all light is produced. Indeed, this discovery
ranks among the numerous recent applications of chemical science to the purposes of life,
which promise to be of the most general utility.
It is evident from the outline here given of the production and application of coal-gas, that all
the uses of pit-coal are not exhausted; it will be sufficient to observe, that the complete
analysis of coal, which has been hitherto confined to the laboratory of the chemist, requiring
skill and nicety in the operator, and attended with great trouble and expence, is now so far
simplified, that many chaldrons of coals may be decomposed by one gas-light apparatus in
the space of six hours, and all the component parts produced in their most useful shape, at an
expence out of all proportion below the value of the products.
SKETCH
OF
THE RISE AND PROGRESS
OF THE
Page 34
DISCOVERY AND APPLICATION
OF
COAL-GAS,
AS A SUBSTITUTE FOR PROCURING
ARTIFICIAL LIGHT.
To assist the reader in comprehending the nature and object of substituting coal-gas for tallow
or oil, for the purpose of obtaining light, it may be proper to touch slightly upon the
successive discoveries that have been made as to the decomposition of coal, and the
application of its different ingredients. Such a sketch will add to the many examples that
occur in the history of science and art, showing the slow progress of mankind in following up
known principles, or extracting from acknowledged facts every possible advantage.
In the Philosophical Transactions of the Royal Society, V. XLI. so long ago as the year 1739,
is recorded a paper, exhibiting an account of some experiments made by Dr. James Clayton,
from which it appears that the inflammable nature of coal-gas was then already known. Dr.
Clayton having distilled Newcastle coal, obtained, as products of the process, an aqueous
fluid, a black oil, and an inflammable gas, which he caught in bladders, and by pricking these
he was enabled to inflame the gas at pleasure.
It is further known, that in the beginning of the last century, Dr. Hales[11] on submitting pit-
coal to a chemical examination, found, that during the ignition of this fossil in close vessels,
nearly one-third of the coal became volatilized in the form of an inflammable vapour. Hence
the discovery of the inflammable nature of coal-gas can no longer be claimed by any person
now living.
[11] Vegetab. Statics, vol. I.
In the year 1767, the Bishop of Llandaff[12] examined the nature of the vapour and gazeous
products evolved during the distillation of pit-coal. This learned philosopher noticed, that the
volatile product is not only inflammable as it issues from the distillatory vessel, but that it
also retained its inflammability after having been made to pass through water, and suffered to
ascend through two high curved tubes. The solid matters obtained by this venerable prelate,
were, an aqueous ammoniacal fluid, a tenaceous oil, resembling tar, an ammoniacal liquor,
and a spongy coal, or coke.
[12] Watson’s Chemical Essays, vol. II.
The first discovery and application of the use of coal-gas for the purpose of illumination is
claimed by Mr. Murdoch.
Dr. W. Henry of Manchester, has published the following account[13] of this discovery.
[13] Thompson’s System of Chemistry, vol. I. p. 52.
“In the year 1792, at which time Mr. Murdoch resided at Redruth, in Cornwall, he
commenced a series of experiments upon the quantity and quality of the gases contained in
different substances. In the course of these he remarked, that the gas obtained by distillation
OF
COAL-GAS,
AS A SUBSTITUTE FOR PROCURING
ARTIFICIAL LIGHT.
To assist the reader in comprehending the nature and object of substituting coal-gas for tallow
or oil, for the purpose of obtaining light, it may be proper to touch slightly upon the
successive discoveries that have been made as to the decomposition of coal, and the
application of its different ingredients. Such a sketch will add to the many examples that
occur in the history of science and art, showing the slow progress of mankind in following up
known principles, or extracting from acknowledged facts every possible advantage.
In the Philosophical Transactions of the Royal Society, V. XLI. so long ago as the year 1739,
is recorded a paper, exhibiting an account of some experiments made by Dr. James Clayton,
from which it appears that the inflammable nature of coal-gas was then already known. Dr.
Clayton having distilled Newcastle coal, obtained, as products of the process, an aqueous
fluid, a black oil, and an inflammable gas, which he caught in bladders, and by pricking these
he was enabled to inflame the gas at pleasure.
It is further known, that in the beginning of the last century, Dr. Hales[11] on submitting pit-
coal to a chemical examination, found, that during the ignition of this fossil in close vessels,
nearly one-third of the coal became volatilized in the form of an inflammable vapour. Hence
the discovery of the inflammable nature of coal-gas can no longer be claimed by any person
now living.
[11] Vegetab. Statics, vol. I.
In the year 1767, the Bishop of Llandaff[12] examined the nature of the vapour and gazeous
products evolved during the distillation of pit-coal. This learned philosopher noticed, that the
volatile product is not only inflammable as it issues from the distillatory vessel, but that it
also retained its inflammability after having been made to pass through water, and suffered to
ascend through two high curved tubes. The solid matters obtained by this venerable prelate,
were, an aqueous ammoniacal fluid, a tenaceous oil, resembling tar, an ammoniacal liquor,
and a spongy coal, or coke.
[12] Watson’s Chemical Essays, vol. II.
The first discovery and application of the use of coal-gas for the purpose of illumination is
claimed by Mr. Murdoch.
Dr. W. Henry of Manchester, has published the following account[13] of this discovery.
[13] Thompson’s System of Chemistry, vol. I. p. 52.
“In the year 1792, at which time Mr. Murdoch resided at Redruth, in Cornwall, he
commenced a series of experiments upon the quantity and quality of the gases contained in
different substances. In the course of these he remarked, that the gas obtained by distillation
Page 35
from coal, peat, wood, and other inflammable substances, burnt with great brilliancy upon
being set fire to; and it occurred to him, that by confining and conducting it through tubes, it
might be employed as an economical substitute for lamps and candles. The distillation was
performed in iron retorts, and the gas conducted through tinned iron and copper tubes to the
distance of 70 feet. At this termination, as well as at intermediate points, the gas was set fire
to, as it passed through apertures of different diameters and forms, purposely varied with a
view of ascertaining which would answer best. In some the gas issued through a number of
small holes like the head of a watering pan; in others it was thrown out in thin long sheets;
and again in others in circular ones, upon the principle of Argand’s lamp. Bags of leather and
of varnished silk, bladders, and vessels of tinned iron, were filled with the gas, which was set
fire to, and carried about from room to room, with a view of ascertaining how far it could be
made to answer the purpose of a moveable or transferable light. Trials were likewise made of
the different quantities and qualities of gas produced by coals of various descriptions, such as
the Swansea, Haverfordwest, Newcastle, Shropshire, Staffordshire, and some kinds of Scotch
coals.
“Mr. Murdoch’s constant occupations prevented his giving farther attention to the subject at
that time; but he again availed himself of a moment of leisure to repeat his experiments upon
coal and peat at Old Cumnock, in Ayrshire, in 1797; and it may be proper to notice that both
these, and the former ones, were exhibited to numerous spectators, who, if necessary, can
attest them. In 1798, he constructed an apparatus at Soho Foundry, which was applied during
many successive nights to the lighting of the building; when the experiments upon different
apertures were repeated and extended upon a large scale. Various methods were also
practised of washing and purifying the air, to get rid of the smoke and smell. These
experiments were continued, with occasional interruptions, until the epoch of the peace in the
spring of 1802, when the illumination of the Soho manufactory afforded an opportunity of
making a public display of the new lights; and they were made to constitute a principal
feature in that exhibition.”
In the year 1803 and 1804, Mr. Winsor exhibited at the Lyceum in London the general nature
of this new mode of illumination though the machinery for procuring, and the manner of
purifying the gas, he kept a secret. He exhibited the mode of conducting the gas through the
house, and a number of devices for chandeliers, lamps, and burners, by which it might be
applied. Among these he proposed long flexible tubes suspended from the ceiling, or wall of
the room, and at the end communicating with burners or lamps of different kinds. This
gentleman showed also by experiment, that the flame of the gas-light, produced no smoke;
that it was not so dangerous as the flame of candles or lamps; that it could not produce
sparks; and that it was not so readily extinguished by gusts of wind or torrents of rain.
Mr. Winsor’s display of gas-lights took place more than two years before Mr. Murdoch’s
priority of right was heard of.
In stating these facts I do not mean to say that Mr. Murdoch derived the hint of applying the
coal-gas from the previous exhibition of Mr. Winsor, because it is quite within the bounds of
probability that the ideas of Mr. Murdoch may have arisen totally independent of all
acquaintance with Mr. Winsor’s.
being set fire to; and it occurred to him, that by confining and conducting it through tubes, it
might be employed as an economical substitute for lamps and candles. The distillation was
performed in iron retorts, and the gas conducted through tinned iron and copper tubes to the
distance of 70 feet. At this termination, as well as at intermediate points, the gas was set fire
to, as it passed through apertures of different diameters and forms, purposely varied with a
view of ascertaining which would answer best. In some the gas issued through a number of
small holes like the head of a watering pan; in others it was thrown out in thin long sheets;
and again in others in circular ones, upon the principle of Argand’s lamp. Bags of leather and
of varnished silk, bladders, and vessels of tinned iron, were filled with the gas, which was set
fire to, and carried about from room to room, with a view of ascertaining how far it could be
made to answer the purpose of a moveable or transferable light. Trials were likewise made of
the different quantities and qualities of gas produced by coals of various descriptions, such as
the Swansea, Haverfordwest, Newcastle, Shropshire, Staffordshire, and some kinds of Scotch
coals.
“Mr. Murdoch’s constant occupations prevented his giving farther attention to the subject at
that time; but he again availed himself of a moment of leisure to repeat his experiments upon
coal and peat at Old Cumnock, in Ayrshire, in 1797; and it may be proper to notice that both
these, and the former ones, were exhibited to numerous spectators, who, if necessary, can
attest them. In 1798, he constructed an apparatus at Soho Foundry, which was applied during
many successive nights to the lighting of the building; when the experiments upon different
apertures were repeated and extended upon a large scale. Various methods were also
practised of washing and purifying the air, to get rid of the smoke and smell. These
experiments were continued, with occasional interruptions, until the epoch of the peace in the
spring of 1802, when the illumination of the Soho manufactory afforded an opportunity of
making a public display of the new lights; and they were made to constitute a principal
feature in that exhibition.”
In the year 1803 and 1804, Mr. Winsor exhibited at the Lyceum in London the general nature
of this new mode of illumination though the machinery for procuring, and the manner of
purifying the gas, he kept a secret. He exhibited the mode of conducting the gas through the
house, and a number of devices for chandeliers, lamps, and burners, by which it might be
applied. Among these he proposed long flexible tubes suspended from the ceiling, or wall of
the room, and at the end communicating with burners or lamps of different kinds. This
gentleman showed also by experiment, that the flame of the gas-light, produced no smoke;
that it was not so dangerous as the flame of candles or lamps; that it could not produce
sparks; and that it was not so readily extinguished by gusts of wind or torrents of rain.
Mr. Winsor’s display of gas-lights took place more than two years before Mr. Murdoch’s
priority of right was heard of.
In stating these facts I do not mean to say that Mr. Murdoch derived the hint of applying the
coal-gas from the previous exhibition of Mr. Winsor, because it is quite within the bounds of
probability that the ideas of Mr. Murdoch may have arisen totally independent of all
acquaintance with Mr. Winsor’s.
Page 36
The claims of invention, or the determination of the right of priority, concerns the public only
so far as the honour and estimation of any useful discovery conferred on the inventor may
induce other individuals to devote their talents to similar pursuits; by means of which, more
discoveries may be made, and the subject of human invention become extended, or rendered
more useful. For as the mere benefits which mankind may derive from any particular
discovery, they are certainly more indebted to the person who first applied the discovery to
actual practice, than to him who first made it, and merely illustrated it by barren experiments.
Mr. Winsor certainly pressed on the mind of the public with unremitted perseverance and
diligence the extensive application of gas-light in the year 1802, but he made no new
discovery with regard to the composition of coal; he did not even invent the mode of
conducting the gas through tubes; and if he has pointed out the particulars of the process, he
has made a very important, though not the most brilliant improvement in this line of business.
Mr. Winsor’s publications are, perhaps, but ill adapted to promote his cause; and the
exaggerated calculation which the sanguine mind of a discoverer is naturally disposed to
indulge in, have, to superficial observers, thrown an air of ridicule and improbability on the
whole scheme of lighting with gas.
It may, however, be safely affirmed, that if the same facts had come forward, under the
sanction of some great name in the chemical or philosophical world, the public incredulity
would long since have been subdued; and the plan, which for many years has been struggling
for existence, would have been eagerly adopted as a national object.
On the 18th of May, 1804, Mr. Frederick Albert Winsor, took out a patent for combining the
saving and purifying of the inflammable gas (for producing light and heat), the ammonia, tar,
and other products of pit-coal, with the manufacture of a superior kind of coke (see
Repertory, 2d Series, v. 172). And, lately, the same gentleman has taken out a second patent,
for further improvements in these processes.
In the year 1805, Mr. Northern, of Leeds, also directed the attention of the public to the
application of coal-gas, as a substitute for tallow light, as will be seen by the following
extract of the Monthly Magazine for April, 1805.
“I distilled in a retort, 50 ounces of pit-coal in a red heat, which gave 6 ounces of a liquid
matter covered with oil, more or less fluid as the heat was increased or diminished. About 26
ounces of cinder remained in the retort; the rest came over in the form of air, as it was
collected in the pneumatic apparatus. I mixed part of it with atmospherical air, and fired it
with the electric spark with a tolerable explosion, which proves it to be hydrogene.—Whether
any of the other gases were mixed with it, I did not then determine. In the receiver I found a
fluid of an acid taste, with a great quantity of oil, and, at the bottom, a substance resembling
tar.
“The apparatus I make use of for producing light is a refiner’s crucible, the top of which
(after filling with coal) I close with a metal cover, luted with clay or other luting, so as to
prevent the escape of the gas; a metal pipe is soldered into the cover, bent so as to come
under the shelf in the pneumatic trough, over which I place a jar with a stop-cock and a small
tube; the jar being previously filled with water, the crucible I place on the common or other
fire as is most convenient; and as the heat increases in it, the gas is forced rapidly through the
so far as the honour and estimation of any useful discovery conferred on the inventor may
induce other individuals to devote their talents to similar pursuits; by means of which, more
discoveries may be made, and the subject of human invention become extended, or rendered
more useful. For as the mere benefits which mankind may derive from any particular
discovery, they are certainly more indebted to the person who first applied the discovery to
actual practice, than to him who first made it, and merely illustrated it by barren experiments.
Mr. Winsor certainly pressed on the mind of the public with unremitted perseverance and
diligence the extensive application of gas-light in the year 1802, but he made no new
discovery with regard to the composition of coal; he did not even invent the mode of
conducting the gas through tubes; and if he has pointed out the particulars of the process, he
has made a very important, though not the most brilliant improvement in this line of business.
Mr. Winsor’s publications are, perhaps, but ill adapted to promote his cause; and the
exaggerated calculation which the sanguine mind of a discoverer is naturally disposed to
indulge in, have, to superficial observers, thrown an air of ridicule and improbability on the
whole scheme of lighting with gas.
It may, however, be safely affirmed, that if the same facts had come forward, under the
sanction of some great name in the chemical or philosophical world, the public incredulity
would long since have been subdued; and the plan, which for many years has been struggling
for existence, would have been eagerly adopted as a national object.
On the 18th of May, 1804, Mr. Frederick Albert Winsor, took out a patent for combining the
saving and purifying of the inflammable gas (for producing light and heat), the ammonia, tar,
and other products of pit-coal, with the manufacture of a superior kind of coke (see
Repertory, 2d Series, v. 172). And, lately, the same gentleman has taken out a second patent,
for further improvements in these processes.
In the year 1805, Mr. Northern, of Leeds, also directed the attention of the public to the
application of coal-gas, as a substitute for tallow light, as will be seen by the following
extract of the Monthly Magazine for April, 1805.
“I distilled in a retort, 50 ounces of pit-coal in a red heat, which gave 6 ounces of a liquid
matter covered with oil, more or less fluid as the heat was increased or diminished. About 26
ounces of cinder remained in the retort; the rest came over in the form of air, as it was
collected in the pneumatic apparatus. I mixed part of it with atmospherical air, and fired it
with the electric spark with a tolerable explosion, which proves it to be hydrogene.—Whether
any of the other gases were mixed with it, I did not then determine. In the receiver I found a
fluid of an acid taste, with a great quantity of oil, and, at the bottom, a substance resembling
tar.
“The apparatus I make use of for producing light is a refiner’s crucible, the top of which
(after filling with coal) I close with a metal cover, luted with clay or other luting, so as to
prevent the escape of the gas; a metal pipe is soldered into the cover, bent so as to come
under the shelf in the pneumatic trough, over which I place a jar with a stop-cock and a small
tube; the jar being previously filled with water, the crucible I place on the common or other
fire as is most convenient; and as the heat increases in it, the gas is forced rapidly through the
Page 37
water into the jar, and regularly displaces it. I then open the cock and put fire to the gas,
which makes its escape through the small tube, and immediately a most beautiful flame
ensues, perfectly free from smoke or smell of any kind. A larger light, but not so vivid or
clear, will be produced without passing the gas through water, but attended with a smoke
somewhat greater than that of a lamp charged with common oil.
“I have great hopes that some active mechanic or chemist will, in the end, hit on a plan to
produce light for large factories, and other purposes, at a much less expence, by the above or
similar means, than is at present produced from oil.”
Soon afterwards, Mr. Samuel Clegg[14] of Manchester, Engineer, communicated an account
of his method of lighting up manufactories with gas-light to the Society of Arts, for which he
received the silver medal.
[14] This gentleman is at present engineer to the Gas-Light Company.
Since that time, the application of gas-light has spread rapidly, and numerous manufactories
and other establishments have been lighted by coal-gas.
In France, the application of gas-lights to economical purposes, was pointed out long before
it was publicly introduced into this country. M. Le Bon had a house fitted up in Paris, in the
winter of 1802, so as to be entirely illuminated by gas-lights, which was seen by thousands
with admiration; and had a brevet d’invention (patent) granted to him by the French
government, for the art of producing light from wood, ignited in close vessels.
Many other attempts have been made to derive advantage from the different ingredients of
coal; but they are too obscure to merit particular enumeration.
In the year 1808, Mr. Murdoch presented to the Royal Society his account of the application
of gas-light, and was complimented with Count Romford’s medal for the same.
The following statement is taken from Mr. Murdoch’s paper.
“The whole of the rooms of the cotton mill of Mr. Lee, at Manchester, which is I believe the
most extensive in the United Kingdom, as well as its counting-houses and store-rooms, and
the adjacent dwelling house of Mr. Lee, are lighted with the gas from coal. The total quantity
of light used during the hours of burning has been ascertained, by a comparison of shadows,
(see page 23) to be about equal to the light which 2500 mould candles, of six to the pound,
would give; each of the candles with which the comparison was made consuming at the rate
of 4-10ths of an ounce (175 grains) of tallow per hour.
“The gas-burners are of two kinds: the one is upon the principle of the Argand lamp, and
resembles it in appearance; the other is a small curved tube with a conical end, having three
circular apertures or perforations, of about a thirtieth of an inch in diameter, one at the point
of the cone, and two lateral ones, through which the gas issues, forming three divergent jets
of flame, somewhat like a fleur-de-lis. The shape and general appearance of this tube has
procured it, among the workmen, the name of the cockspur burner.
“The number of burners employed in all the buildings amounts to 271 Argand, and 653
cockspurs, each of the former giving a light equal to that of four candles of the description
which makes its escape through the small tube, and immediately a most beautiful flame
ensues, perfectly free from smoke or smell of any kind. A larger light, but not so vivid or
clear, will be produced without passing the gas through water, but attended with a smoke
somewhat greater than that of a lamp charged with common oil.
“I have great hopes that some active mechanic or chemist will, in the end, hit on a plan to
produce light for large factories, and other purposes, at a much less expence, by the above or
similar means, than is at present produced from oil.”
Soon afterwards, Mr. Samuel Clegg[14] of Manchester, Engineer, communicated an account
of his method of lighting up manufactories with gas-light to the Society of Arts, for which he
received the silver medal.
[14] This gentleman is at present engineer to the Gas-Light Company.
Since that time, the application of gas-light has spread rapidly, and numerous manufactories
and other establishments have been lighted by coal-gas.
In France, the application of gas-lights to economical purposes, was pointed out long before
it was publicly introduced into this country. M. Le Bon had a house fitted up in Paris, in the
winter of 1802, so as to be entirely illuminated by gas-lights, which was seen by thousands
with admiration; and had a brevet d’invention (patent) granted to him by the French
government, for the art of producing light from wood, ignited in close vessels.
Many other attempts have been made to derive advantage from the different ingredients of
coal; but they are too obscure to merit particular enumeration.
In the year 1808, Mr. Murdoch presented to the Royal Society his account of the application
of gas-light, and was complimented with Count Romford’s medal for the same.
The following statement is taken from Mr. Murdoch’s paper.
“The whole of the rooms of the cotton mill of Mr. Lee, at Manchester, which is I believe the
most extensive in the United Kingdom, as well as its counting-houses and store-rooms, and
the adjacent dwelling house of Mr. Lee, are lighted with the gas from coal. The total quantity
of light used during the hours of burning has been ascertained, by a comparison of shadows,
(see page 23) to be about equal to the light which 2500 mould candles, of six to the pound,
would give; each of the candles with which the comparison was made consuming at the rate
of 4-10ths of an ounce (175 grains) of tallow per hour.
“The gas-burners are of two kinds: the one is upon the principle of the Argand lamp, and
resembles it in appearance; the other is a small curved tube with a conical end, having three
circular apertures or perforations, of about a thirtieth of an inch in diameter, one at the point
of the cone, and two lateral ones, through which the gas issues, forming three divergent jets
of flame, somewhat like a fleur-de-lis. The shape and general appearance of this tube has
procured it, among the workmen, the name of the cockspur burner.
“The number of burners employed in all the buildings amounts to 271 Argand, and 653
cockspurs, each of the former giving a light equal to that of four candles of the description
Page 38
above-mentioned; and each of the latter a light equal to two and a quarter of the same
candles; making therefore the total of the gas-light a little more than equal to that of 2500
candles, six to the pound. When thus regulated, the whole of the above burners require an
hourly supply of 1250 cubic feet of the gas produced from cannel-coal; the superior quality
and quantity of the gas produced from that material having given it a decided preference in
this situation over every other coal, notwithstanding its higher price.
“The time during which the gas-light is used may, upon an average of the whole year, be
stated at least at two hours per day of 24 hours. In some mills, where there is over work, it
will be three hours; and in the few where night work is still continued nearly 12 hours. But
taking two hours per day as the common average throughout the year, the consumption in
Messrs. Philips and Lee’s mill will be 1250 × 2 = 2500 cubic feet of gas per day; to produce
which 700 weight of cannel-coal is required in the retort. The price of the best Wiggan
cannel-coal (the sort used) is 131⁄2d. per cwt. (22s. 6d. per ton) delivered at the mill, or say
about eight shillings for the seven hundred weight. Multiplying by the number of working
days in the year (313,) the annual consumption of coal will be 110 tons, and its cost 125l.
“About one-third of the above quantity, or say forty tons of good common coal, value ten
shillings per ton, is required for fuel to heat the retorts, the annual amount of which is 20l.
“The 110 tons of cannel-coal, when distilled, produce about 70 tons of good coke, which is
sold upon the spot at 1s. 4d. per cwt. and will therefore amount annually to the sum of 93l.
“The quantity of tar produced from each ton of cannel-coal is from 11 to 12 ale gallons,
making a total annual produce of about 1250 ale gallons, which not having been yet sold, it
cannot yet be determined its value.
“The interest of the capital expended in the necessary apparatus and buildings, together with
what is considered as an ample allowance for wear and tear, is stated by Mr. Lee at about
550l. per annum, in which some allowance is made for this apparatus being made upon a
scale adequate to the supply of a still greater quantity of light, than he has occasion to make
use of.
“Mr. Lee is of opinion that the cost of attendance upon candles would be as much, if not
more, than upon the gas apparatus; so that, in forming the comparison, nothing need be stated
upon that score, on either side.
“The economical statement for one year, then, stands thus:
Cost of 110 tons of cannel coal £ 125
Ditto of 40 tons of common ditto, to carbonise 20
In all 145
Deduct the value of 70 tons of coke 93
The annual expenditure in coal, after deducting the value of the coke, and without
allowing any thing for the tar, is therefore 52
And the interest of capital sunk, and wear and tear of apparatus 550
Making the total expence of the gas apparatus per annum, about 600
candles; making therefore the total of the gas-light a little more than equal to that of 2500
candles, six to the pound. When thus regulated, the whole of the above burners require an
hourly supply of 1250 cubic feet of the gas produced from cannel-coal; the superior quality
and quantity of the gas produced from that material having given it a decided preference in
this situation over every other coal, notwithstanding its higher price.
“The time during which the gas-light is used may, upon an average of the whole year, be
stated at least at two hours per day of 24 hours. In some mills, where there is over work, it
will be three hours; and in the few where night work is still continued nearly 12 hours. But
taking two hours per day as the common average throughout the year, the consumption in
Messrs. Philips and Lee’s mill will be 1250 × 2 = 2500 cubic feet of gas per day; to produce
which 700 weight of cannel-coal is required in the retort. The price of the best Wiggan
cannel-coal (the sort used) is 131⁄2d. per cwt. (22s. 6d. per ton) delivered at the mill, or say
about eight shillings for the seven hundred weight. Multiplying by the number of working
days in the year (313,) the annual consumption of coal will be 110 tons, and its cost 125l.
“About one-third of the above quantity, or say forty tons of good common coal, value ten
shillings per ton, is required for fuel to heat the retorts, the annual amount of which is 20l.
“The 110 tons of cannel-coal, when distilled, produce about 70 tons of good coke, which is
sold upon the spot at 1s. 4d. per cwt. and will therefore amount annually to the sum of 93l.
“The quantity of tar produced from each ton of cannel-coal is from 11 to 12 ale gallons,
making a total annual produce of about 1250 ale gallons, which not having been yet sold, it
cannot yet be determined its value.
“The interest of the capital expended in the necessary apparatus and buildings, together with
what is considered as an ample allowance for wear and tear, is stated by Mr. Lee at about
550l. per annum, in which some allowance is made for this apparatus being made upon a
scale adequate to the supply of a still greater quantity of light, than he has occasion to make
use of.
“Mr. Lee is of opinion that the cost of attendance upon candles would be as much, if not
more, than upon the gas apparatus; so that, in forming the comparison, nothing need be stated
upon that score, on either side.
“The economical statement for one year, then, stands thus:
Cost of 110 tons of cannel coal £ 125
Ditto of 40 tons of common ditto, to carbonise 20
In all 145
Deduct the value of 70 tons of coke 93
The annual expenditure in coal, after deducting the value of the coke, and without
allowing any thing for the tar, is therefore 52
And the interest of capital sunk, and wear and tear of apparatus 550
Making the total expence of the gas apparatus per annum, about 600
Page 39
“That of candles, to give the same light, would be about 2000l. For each candle, consuming
at the rate of 4-10ths of an ounce of tallow per hour, the 2500 candles burning, upon an
average of the year, two hours per day, would, at one shilling per pound, the present price,
amount to nearly the sum of money above-mentioned.
“If the comparison were made upon an average of three hours per day, as in most cases,
would perhaps be nearer to the truth, and the tear and wear remaining nearly the same as on
the former case, the whole cost would not exceed 650l. while that of the tallow would be
3000l.”
Mr. Ackerman in this metropolis, has shown that the art of gas-light illumination is not
confined to great manufactories, but that its advantages are equally applicable to those on a
moderate scale. The whole of Mr. Ackerman’s establishment, his public library, warehouse,
printing-offices and work-shops, together with his dwelling house, from the kitchen to the
drawing-room, has, for these four years past, been lighted with gas, to the total exclusion of
all other lights. The result of the whole of this proceeding will be obvious from the following
letter:
To Mr. ACCUM.
Sir,
“In answer to your request with regard to my gas-lights, which I now have in my house, I take this mode of informing you,
that I charge two retorts with 240lbs. of coal, half cannel and half Newcastle, from which I extract 1000 cubic feet of gas. To
obtain this quantity of gas, when the retorts are cold, I use from 100 to 110lb. of common coals; but when they are in a
working state, that is to say, when they are once red hot, the carbonising fuel amounts to about 25lb. per retort. The bulk of
gas thus obtained supplies 40 Argand’s lamps, of the large size, for four hours per night, during the long winter evenings,
together with eight Argand’s lamps and about 22 single cockspur burners, for three hours per night: in addition to which my
printers employ 16 cockspur burners for ten hours per day to heat their plates instead of charcoal fire. In the depth of winter
we charge two retorts per day: but, upon an average, we work 365 retorts in 365 days.
Now 365 retorts containing 120lb. of coal each, make 43800lb. which is equal to ten chaldrons of Newcastle and eight tons
of cannel coal.
10 chaldrons of Newcastle coals, at 65s. make £ 32 10 0
8 tons of cannel coal,[15] (this coal is sold by weight) at 100s. per ton 40 0 0
7 chaldrons of common coals for carbonising, at 55s. 19 5 0
To wages paid the servant for attending the gas apparatus 30 0 0
Interest of money sunk 30 0 0
The wear and tear of the gas-light apparatus I consider to be equal to the wear and tear of lamps,
candlesticks, &c. employed for oil, tallow, &c.
Total expence of the gas lights 151 15 0
DEDUCT
23 chaldrons of coke, at 60s. per chaldron 69
Ammoniacal liquor 5
Tar 6
Charcoal employed by the copper-plate printers to heat their plates, which is now done with
the gas-light flame, cost, annually 25
Two chaldrons of coals minus used as fuel, for warming the house, since the adoption of the
gas-lights, at 65s. per chaldron 6 10
111 10 0
Nett expences of the gas-lights £ 40 5 0
The lights used in my Establishment, prior to the gas-lights, amounted annually to 160 0 0
My present system of lighting with gas costs, per ann. 40 5 0
at the rate of 4-10ths of an ounce of tallow per hour, the 2500 candles burning, upon an
average of the year, two hours per day, would, at one shilling per pound, the present price,
amount to nearly the sum of money above-mentioned.
“If the comparison were made upon an average of three hours per day, as in most cases,
would perhaps be nearer to the truth, and the tear and wear remaining nearly the same as on
the former case, the whole cost would not exceed 650l. while that of the tallow would be
3000l.”
Mr. Ackerman in this metropolis, has shown that the art of gas-light illumination is not
confined to great manufactories, but that its advantages are equally applicable to those on a
moderate scale. The whole of Mr. Ackerman’s establishment, his public library, warehouse,
printing-offices and work-shops, together with his dwelling house, from the kitchen to the
drawing-room, has, for these four years past, been lighted with gas, to the total exclusion of
all other lights. The result of the whole of this proceeding will be obvious from the following
letter:
To Mr. ACCUM.
Sir,
“In answer to your request with regard to my gas-lights, which I now have in my house, I take this mode of informing you,
that I charge two retorts with 240lbs. of coal, half cannel and half Newcastle, from which I extract 1000 cubic feet of gas. To
obtain this quantity of gas, when the retorts are cold, I use from 100 to 110lb. of common coals; but when they are in a
working state, that is to say, when they are once red hot, the carbonising fuel amounts to about 25lb. per retort. The bulk of
gas thus obtained supplies 40 Argand’s lamps, of the large size, for four hours per night, during the long winter evenings,
together with eight Argand’s lamps and about 22 single cockspur burners, for three hours per night: in addition to which my
printers employ 16 cockspur burners for ten hours per day to heat their plates instead of charcoal fire. In the depth of winter
we charge two retorts per day: but, upon an average, we work 365 retorts in 365 days.
Now 365 retorts containing 120lb. of coal each, make 43800lb. which is equal to ten chaldrons of Newcastle and eight tons
of cannel coal.
10 chaldrons of Newcastle coals, at 65s. make £ 32 10 0
8 tons of cannel coal,[15] (this coal is sold by weight) at 100s. per ton 40 0 0
7 chaldrons of common coals for carbonising, at 55s. 19 5 0
To wages paid the servant for attending the gas apparatus 30 0 0
Interest of money sunk 30 0 0
The wear and tear of the gas-light apparatus I consider to be equal to the wear and tear of lamps,
candlesticks, &c. employed for oil, tallow, &c.
Total expence of the gas lights 151 15 0
DEDUCT
23 chaldrons of coke, at 60s. per chaldron 69
Ammoniacal liquor 5
Tar 6
Charcoal employed by the copper-plate printers to heat their plates, which is now done with
the gas-light flame, cost, annually 25
Two chaldrons of coals minus used as fuel, for warming the house, since the adoption of the
gas-lights, at 65s. per chaldron 6 10
111 10 0
Nett expences of the gas-lights £ 40 5 0
The lights used in my Establishment, prior to the gas-lights, amounted annually to 160 0 0
My present system of lighting with gas costs, per ann. 40 5 0
Page 40
Balance in favor of the gas for one year £ 119 15 0
Page 41
[15] Although cannel-coal sells at nearly double the price of Newcastle coal, I use it in
preference to the latter, because it affords a larger portion of gas, and gives a much more
brilliant light.
Such is the simple statement of my present system of lighting, the brilliancy of which, when
contrasted with our former lights, bears the same comparison to them as a bright summer sun-shine
does to a murky November day: nor are we, as formerly, almost suffocated with the effluvia of
charcoal and fumes of candles and lamps. In addition to this, the damage sustained by the spilling of
oil and tallow upon prints, drawings, books and paper, &c. amounted annually to upwards of 50l. All
the workmen employed in my establishment consider their gas-lights as the greatest blessing; and I
have only to add, that the light we now enjoy, were it to be produced by means of Argand’s lamps or
candles, would cost at least 350l. per annum.
I am, with respect,
Strand, March 13, Yours,
1815. R. ACKERMAN.”
Another manufacturer who was one of the first that adopted the use of this
method of illumination in the small way, and who gave a statement of its
advantages to the public, is Mr. Cook, a manufacturer of metal toys, at
Birmingham, a clear-headed, prudent man, not apt to be dazzled by a
fanciful speculation, but governed in his transactions by a simple balance of
profit and loss. There is a naïveté in his own account of the process which
will amuse as well as instruct the reader.
“My apparatus is simply a small cast-iron pot, of about eight gallons, with a
cast-iron cover, which I lute to it with sand. Into this pot I put my coal. I
pass the gas through water into the gasometer or reservoir, which holds
about 400 gallons; and, by means of old gun-barrels, convey it all round my
shops. Now, from twenty or twenty-five pounds of coal, I make perhaps six
hundred gallons[16] of gas; for, when my reservoir is full, we are forced to
burn away the overplus in waste, unless we have work to use it as it is
made: but, in general, we go on making and using it, so that I cannot tell to
fifty or a hundred gallons;—and, in fact, a great deal depends on the coals,
some coals making much more than others. These twenty-five pounds of
coal put into the retort, and say twenty-five pounds more to heat the retort,
which is more than it does take one time with another, but I am willing to
say the utmost, are worth four-pence per day. From this four-pence we burn
eighteen or twenty lights during the winter season.”
[16] A wine-gallon is equal to 231 cubic inches.
preference to the latter, because it affords a larger portion of gas, and gives a much more
brilliant light.
Such is the simple statement of my present system of lighting, the brilliancy of which, when
contrasted with our former lights, bears the same comparison to them as a bright summer sun-shine
does to a murky November day: nor are we, as formerly, almost suffocated with the effluvia of
charcoal and fumes of candles and lamps. In addition to this, the damage sustained by the spilling of
oil and tallow upon prints, drawings, books and paper, &c. amounted annually to upwards of 50l. All
the workmen employed in my establishment consider their gas-lights as the greatest blessing; and I
have only to add, that the light we now enjoy, were it to be produced by means of Argand’s lamps or
candles, would cost at least 350l. per annum.
I am, with respect,
Strand, March 13, Yours,
1815. R. ACKERMAN.”
Another manufacturer who was one of the first that adopted the use of this
method of illumination in the small way, and who gave a statement of its
advantages to the public, is Mr. Cook, a manufacturer of metal toys, at
Birmingham, a clear-headed, prudent man, not apt to be dazzled by a
fanciful speculation, but governed in his transactions by a simple balance of
profit and loss. There is a naïveté in his own account of the process which
will amuse as well as instruct the reader.
“My apparatus is simply a small cast-iron pot, of about eight gallons, with a
cast-iron cover, which I lute to it with sand. Into this pot I put my coal. I
pass the gas through water into the gasometer or reservoir, which holds
about 400 gallons; and, by means of old gun-barrels, convey it all round my
shops. Now, from twenty or twenty-five pounds of coal, I make perhaps six
hundred gallons[16] of gas; for, when my reservoir is full, we are forced to
burn away the overplus in waste, unless we have work to use it as it is
made: but, in general, we go on making and using it, so that I cannot tell to
fifty or a hundred gallons;—and, in fact, a great deal depends on the coals,
some coals making much more than others. These twenty-five pounds of
coal put into the retort, and say twenty-five pounds more to heat the retort,
which is more than it does take one time with another, but I am willing to
say the utmost, are worth four-pence per day. From this four-pence we burn
eighteen or twenty lights during the winter season.”
[16] A wine-gallon is equal to 231 cubic inches.
Page 42
Thus are the candles which Mr. Cook used to employ, and which cost him
three shillings a day, entirely superseded. But, besides his expence in
candles, oil and cotton for soldering, used to cost him full 30l. a year; which
is entirely saved, as he now does all his soldering by the gas flame only. For
“in all trades in which the blow-pipe is used with oil and cotton, or where
charcoal is employed to produce a moderate heat, the gas flame will be
found much superior, both as to quickness and neatness in the work: the
flame is sharper, and is constantly ready for use; while, with oil and cotton
or charcoal, the workman is always obliged to wait for his lamp or coal
getting up; that is, till it is sufficiently on fire to do his work. Thus, a great
quantity of oil is always burned away useless; but, with the gas, the moment
the stop-cock is turned, the lamp is ready, and not a moment is lost.” We
must refer to Mr. Cook’s letter for the details of expence, which he gives
with faithful minuteness, and always leaning to the side unfavourable to the
gas. The result of the whole is, that he saves 30l. out of the 50l. which his
lights formerly cost him: and, when we consider that his calculation allows
the gas-lights to burn the whole year, and the candles only twenty weeks,
there can be little doubt, that the savings in this case follow nearly the same
proportion as in the former. If the apparatus be erected even on a smaller
scale, “the saving,” Mr. Cook assures us, “will still be considerable: for the
poor man, who lights only six candles, or uses one lamp, if the apparatus is
put up in the cheapest way possible, will find it only cost him 10l. or 12l.
which he will nearly, if not quite, save the first year.”
Mr. Ackerman having, in this town, set the example of lighting his
establishment with gas, several other individuals soon followed the attempt.
The following statement will show, that this species of light may be made
use of with the greatest advantage, upon a still smaller scale, where no great
nicety with regard to the apparatus for procuring gas is required. The
following report I have received from Messrs. Lloyd, of Queen Street,
Southwark, thimble manufacturers and whitesmiths, who have used the gas-
light for soldering and other purposes these five years past.
From 4 pecks or 1 bushel of coals, weighing 69lbs. for
which we now pay (1809) 1s. we produce 43⁄4 pecks of coke
and 1⁄2 peck of coal not carbonised remains in the distilling
pot, which together with the coke weighs 58lbs. 6 oz. value
at 1s. per bushel 0 1 4
three shillings a day, entirely superseded. But, besides his expence in
candles, oil and cotton for soldering, used to cost him full 30l. a year; which
is entirely saved, as he now does all his soldering by the gas flame only. For
“in all trades in which the blow-pipe is used with oil and cotton, or where
charcoal is employed to produce a moderate heat, the gas flame will be
found much superior, both as to quickness and neatness in the work: the
flame is sharper, and is constantly ready for use; while, with oil and cotton
or charcoal, the workman is always obliged to wait for his lamp or coal
getting up; that is, till it is sufficiently on fire to do his work. Thus, a great
quantity of oil is always burned away useless; but, with the gas, the moment
the stop-cock is turned, the lamp is ready, and not a moment is lost.” We
must refer to Mr. Cook’s letter for the details of expence, which he gives
with faithful minuteness, and always leaning to the side unfavourable to the
gas. The result of the whole is, that he saves 30l. out of the 50l. which his
lights formerly cost him: and, when we consider that his calculation allows
the gas-lights to burn the whole year, and the candles only twenty weeks,
there can be little doubt, that the savings in this case follow nearly the same
proportion as in the former. If the apparatus be erected even on a smaller
scale, “the saving,” Mr. Cook assures us, “will still be considerable: for the
poor man, who lights only six candles, or uses one lamp, if the apparatus is
put up in the cheapest way possible, will find it only cost him 10l. or 12l.
which he will nearly, if not quite, save the first year.”
Mr. Ackerman having, in this town, set the example of lighting his
establishment with gas, several other individuals soon followed the attempt.
The following statement will show, that this species of light may be made
use of with the greatest advantage, upon a still smaller scale, where no great
nicety with regard to the apparatus for procuring gas is required. The
following report I have received from Messrs. Lloyd, of Queen Street,
Southwark, thimble manufacturers and whitesmiths, who have used the gas-
light for soldering and other purposes these five years past.
From 4 pecks or 1 bushel of coals, weighing 69lbs. for
which we now pay (1809) 1s. we produce 43⁄4 pecks of coke
and 1⁄2 peck of coal not carbonised remains in the distilling
pot, which together with the coke weighs 58lbs. 6 oz. value
at 1s. per bushel 0 1 4
Page 43
we procure 6lbs. 4 oz. of tar which we use as pith—it saves
us 0 1 0
0 2 4
Deduct for coal 0 1 0
Profit on coke and tar 0 1 0
The gas yielded by the 4 pecks of coals in the pot, make 42
brilliant lights, which burn 7 hours. To keep 42 tallow
candles which were formerly used in the manufactory
burning for the same time, required 7lbs. which at 1s. per lb.
cost 0 7 0
To this, add profits on coke and tar 0 1 0
Gained out of every bushel of coal 0 8 0
“The gas-burners made use of in our manufactory produce jets of flame,
which in our business, where much soldering with the blow-pipe must be
done, have a decided superiority over Argand’s lamps. We are not nice
concerning the quality of the gas—a great part of it is burned from the
gasometer, without allowing it to purify itself in the gasometer, because our
gasometer is not large enough to store up the whole quantity of gas we want
for use.”
THEORY
OF
THE PRODUCTION OF GAS-LIGHT,
AND
DESCRIPTION
OF
A PORTABLE APPARATUS
FOR EXHIBITING, IN THE SMALL WAY, THE GENERAL
NATURE OF THIS SPECIES OF LIGHT.
To obtain carburetted hidrogen, or coal-gas, from common pit-coal, and to
apply it for the purposes of illumination, the coal is introduced into large
us 0 1 0
0 2 4
Deduct for coal 0 1 0
Profit on coke and tar 0 1 0
The gas yielded by the 4 pecks of coals in the pot, make 42
brilliant lights, which burn 7 hours. To keep 42 tallow
candles which were formerly used in the manufactory
burning for the same time, required 7lbs. which at 1s. per lb.
cost 0 7 0
To this, add profits on coke and tar 0 1 0
Gained out of every bushel of coal 0 8 0
“The gas-burners made use of in our manufactory produce jets of flame,
which in our business, where much soldering with the blow-pipe must be
done, have a decided superiority over Argand’s lamps. We are not nice
concerning the quality of the gas—a great part of it is burned from the
gasometer, without allowing it to purify itself in the gasometer, because our
gasometer is not large enough to store up the whole quantity of gas we want
for use.”
THEORY
OF
THE PRODUCTION OF GAS-LIGHT,
AND
DESCRIPTION
OF
A PORTABLE APPARATUS
FOR EXHIBITING, IN THE SMALL WAY, THE GENERAL
NATURE OF THIS SPECIES OF LIGHT.
To obtain carburetted hidrogen, or coal-gas, from common pit-coal, and to
apply it for the purposes of illumination, the coal is introduced into large
Page 44
iron cylinders, called retorts, to the apertures of which iron pipes are
adapted, terminating in a vessel, or vessels, destined to purify and collect
the gas. The retorts charged with coals and made air-tight, are placed upon
the fire, the action of which extricates the gazeous products from the coals,
together with an aqueous ammoniacal vapour, and a tenaceous bituminous
fluid, or tar, &c. The liquid substances are conveyed into proper vessels,
and the gazeous products are conducted, by means of pipes, under the
gasometer, where the gas is again washed, and remains ready for use. There
are also other pipes leading from the gasometer, which branch out into
smaller ramifications, until they terminate at the places where the lights are
wanted. The extremities of the pipes have small apertures, out of which the
gas issues, and the streams of gas being lighted at those apertures burn with
a clear and steady flame as long as the supply of gas continues. All the
pipes which come from the gasometer are furnished at their extremities with
stop-cocks to regulate the admission of the gas. The burners are formed in
various ways, either a tube ending with a simple orifice, at which the gas
issues in a stream, and if once lighted will continue to burn with the most
steady and regular light imaginable, as long as the gas is supplied; or two
concentric tubes of brass, or sheet-iron, are placed at a distance of a small
fraction of an inch from each other, and closed at the bottom. The gas which
enters between these cylinders, when lighted, forms an Argand lamp, which
is supplied by an internal and external current of air in the usual manner. Or
the two concentric tubes are closed at the top with a ring having small
perforations, out of which the gas alone can issue, thus forming small
distinct streams of light.
adapted, terminating in a vessel, or vessels, destined to purify and collect
the gas. The retorts charged with coals and made air-tight, are placed upon
the fire, the action of which extricates the gazeous products from the coals,
together with an aqueous ammoniacal vapour, and a tenaceous bituminous
fluid, or tar, &c. The liquid substances are conveyed into proper vessels,
and the gazeous products are conducted, by means of pipes, under the
gasometer, where the gas is again washed, and remains ready for use. There
are also other pipes leading from the gasometer, which branch out into
smaller ramifications, until they terminate at the places where the lights are
wanted. The extremities of the pipes have small apertures, out of which the
gas issues, and the streams of gas being lighted at those apertures burn with
a clear and steady flame as long as the supply of gas continues. All the
pipes which come from the gasometer are furnished at their extremities with
stop-cocks to regulate the admission of the gas. The burners are formed in
various ways, either a tube ending with a simple orifice, at which the gas
issues in a stream, and if once lighted will continue to burn with the most
steady and regular light imaginable, as long as the gas is supplied; or two
concentric tubes of brass, or sheet-iron, are placed at a distance of a small
fraction of an inch from each other, and closed at the bottom. The gas which
enters between these cylinders, when lighted, forms an Argand lamp, which
is supplied by an internal and external current of air in the usual manner. Or
the two concentric tubes are closed at the top with a ring having small
perforations, out of which the gas alone can issue, thus forming small
distinct streams of light.
Page 45
Larger image (279 kB)
The gas-apparatus, plate 2, will be found very convenient for exhibiting, in
the small way, the general nature of this new art of illumination, whilst at
the same time it may serve to ascertain, at a trifling expence, the
comparative value of different kinds of coals intended to be employed for
the production of this species of light, as well as other occasional purposes
connected with the gas-light system of illumination.
It consists of three distinct apparatus:—namely, a portable furnace, fig. 1,
plate 2, by means of which the gas is prepared—fig. 2, a purifyer, or
condenser, which separates and purifies the products obtained from the
coal, so as to render the gas fit for the purpose of illumination—fig. 3, a
gasometer, or reservoir for receiving and preserving the purified stock of
gas, and from which it may be transferred and distributed as occasion may
require. The following statement will explain more fully the general nature
of this portable chamber apparatus:—a, represents a cast iron retort, such as
is used for chemical operations in the small way. This retort rests upon a
tripod of hammered iron, placed upon the bars of the grate of the chemical
furnace. Into this retort the coals are put for furnishing the gas. It is
The gas-apparatus, plate 2, will be found very convenient for exhibiting, in
the small way, the general nature of this new art of illumination, whilst at
the same time it may serve to ascertain, at a trifling expence, the
comparative value of different kinds of coals intended to be employed for
the production of this species of light, as well as other occasional purposes
connected with the gas-light system of illumination.
It consists of three distinct apparatus:—namely, a portable furnace, fig. 1,
plate 2, by means of which the gas is prepared—fig. 2, a purifyer, or
condenser, which separates and purifies the products obtained from the
coal, so as to render the gas fit for the purpose of illumination—fig. 3, a
gasometer, or reservoir for receiving and preserving the purified stock of
gas, and from which it may be transferred and distributed as occasion may
require. The following statement will explain more fully the general nature
of this portable chamber apparatus:—a, represents a cast iron retort, such as
is used for chemical operations in the small way. This retort rests upon a
tripod of hammered iron, placed upon the bars of the grate of the chemical
furnace. Into this retort the coals are put for furnishing the gas. It is
Page 46
provided with a solid iron stopper ground air-tight into the mouth of the
retort, and the stopper is secured in its place by an iron wedge passing over
it in the centre; by means of which the mouth of the retort when charged
with coal is readily made air-tight, and the stopper may easily be removed
by knocking out the iron wedge. b. is a metal pipe which conveys all the
distillatory products from the retort into the purifier fig. 2. This tube is bent
at right angles at the extremity where it enters the intermediate vessel fig. 2.
The purifier fig. 2, is divided into three compartments marked c. d. e. The
first compartment is filled with water, and by means of it an air-tight
communication is established with the retort which furnishes the gas. The
second compartment, d, contains a solution of caustic pot-ash composed of
about 2 parts of caustic pot-ash and 16 of water, or a mixture of quick-lime
and water of the consistence of very thin cream. The object of this
compartment is to separate the non-inflammable gases and other products
evolved during the distillation of the coal, from the carburetted hidrogen or
coal-gas, so as to render it fit for use. The third compartment e is left empty
to receive the tar and other liquid products. Into the first compartment c, all
the gazeous and liquid products are delivered, as they become evolved
during the distillation, by means of the pipe b. The compartment d, of the
purifier, or alcali vessel, is furnished with a wide perpendicular pipe, which
serves to make an air-tight communication with the retort, by allowing the
tube b, to pass readily through it. From the chamber c, the liquid and
gazeous products pass to the tar-chamber, or compartment e, by means of
the descending pipe f. The tar and other condensible substances are
therefore deposited at e, whilst the gazeous products alone ascend from the
tar-chamber e, by the pipe g, and down again the pipe h, (which is closed at
the top) into the compartment d, of the vessel or purifier, fig. 2. The gas
being thus made to pass from the compartment e, up into the pipe g, and
down the pipe h, (which is closed at the top) into the purifier d, is brought
into contact with the liquor in that vessel, where it is opposed to a pressure
in proportion to the perpendicular height of the column of liquid which it
contains. The funnel in the compartment c, is considerably higher than the
purifying apparatus, it therefore allows the liquid which it contains, when
pressed upon by the gas, to ascend into it, without overflowing the
apparatus, and to descend again as the pressure diminishes—i is another
wide-mouth funnel, by means of which the chamber d, is filled with the
alcaline solution, or mixture of lime and water. The carbonic acid gas and
retort, and the stopper is secured in its place by an iron wedge passing over
it in the centre; by means of which the mouth of the retort when charged
with coal is readily made air-tight, and the stopper may easily be removed
by knocking out the iron wedge. b. is a metal pipe which conveys all the
distillatory products from the retort into the purifier fig. 2. This tube is bent
at right angles at the extremity where it enters the intermediate vessel fig. 2.
The purifier fig. 2, is divided into three compartments marked c. d. e. The
first compartment is filled with water, and by means of it an air-tight
communication is established with the retort which furnishes the gas. The
second compartment, d, contains a solution of caustic pot-ash composed of
about 2 parts of caustic pot-ash and 16 of water, or a mixture of quick-lime
and water of the consistence of very thin cream. The object of this
compartment is to separate the non-inflammable gases and other products
evolved during the distillation of the coal, from the carburetted hidrogen or
coal-gas, so as to render it fit for use. The third compartment e is left empty
to receive the tar and other liquid products. Into the first compartment c, all
the gazeous and liquid products are delivered, as they become evolved
during the distillation, by means of the pipe b. The compartment d, of the
purifier, or alcali vessel, is furnished with a wide perpendicular pipe, which
serves to make an air-tight communication with the retort, by allowing the
tube b, to pass readily through it. From the chamber c, the liquid and
gazeous products pass to the tar-chamber, or compartment e, by means of
the descending pipe f. The tar and other condensible substances are
therefore deposited at e, whilst the gazeous products alone ascend from the
tar-chamber e, by the pipe g, and down again the pipe h, (which is closed at
the top) into the compartment d, of the vessel or purifier, fig. 2. The gas
being thus made to pass from the compartment e, up into the pipe g, and
down the pipe h, (which is closed at the top) into the purifier d, is brought
into contact with the liquor in that vessel, where it is opposed to a pressure
in proportion to the perpendicular height of the column of liquid which it
contains. The funnel in the compartment c, is considerably higher than the
purifying apparatus, it therefore allows the liquid which it contains, when
pressed upon by the gas, to ascend into it, without overflowing the
apparatus, and to descend again as the pressure diminishes—i is another
wide-mouth funnel, by means of which the chamber d, is filled with the
alcaline solution, or mixture of lime and water. The carbonic acid gas and
Page 47
sulphuretted hidrogen, evolved during the distillation of the coal, are thus
made to combine with the alcali or lime, in the compartment d, of the
purifier, forming carbonate and hidro-sulphuret of lime. The carburetted
hidrogen, being left more or less pure, is conveyed through the pipe k, into
the gasometer, fig. 3. The communication of the purifier, fig. 2, with the
gasometer, is made by means of the well-known water-valve l, placed so
that the communicating tube k, may be easily removed at pleasure—m, is a
cock for drawing off the tar, &c. n, a gauge-cock for ascertaining the height
of the liquid in the chamber d. The gasometer, fig. 3, the object of which is
to store up the gas, consists of two principal parts—namely, a large interior
vessel designed to contain the gas, and an outer cistern or vessel, of rather
greater capacity, in which the former is suspended, designed to contain the
water by which the gas is confined. The interior vessel which contains the
gas is suspended by chains or cords hung over pullies, to which weights are
attached, so as to nearly equipoise it. o is a pipe, which communicates with
the water-valve l, and by means of which the gas passes from the purifier,
fig. 2, into the gasometer. The upper end of this pipe is covered, in the
manner of a hood, by a cylindrical vessel p, open at bottom, but partially
immersed beneath the surface of the water contained in the outer cistern of
the gasometer, and perforated round near the lower edge with a number of
small holes. The gas displaces the water from this receiver p, and escapes
through the small holes, rising in bubbles through the water, so as to expose
a large surface to its action, that it may be properly washed, &c. After rising
through the water the gas enters the gasometer, which is suspended to move
up and down by the chains, pullies, and balance-weights, q. From the centre
of the gasometer a tube, r, descends, which includes a pipe, s, fixed
perpendicular from the bottom of the cistern. The fixed pipe r, forms a
guide to keep the gasometer always perpendicular. t is also an iron pipe
made fast in the centre of the inner vessel, and communicates with the
upright tube, s, in the outer vessel. This contrivance obliges the gas to pass
into the pipe t, whilst it also serves to keep the gasometer steady when
nearly out of the outer cistern.
When the operation commences, the gasometer is sunk down nearly to a
level with the surface of the water in the outer cistern, and is consequently
filled with water; but as the gas enters, it rises up to receive it. It is to be
noted, that the balance-weights q q, should not be quite so heavy as the
made to combine with the alcali or lime, in the compartment d, of the
purifier, forming carbonate and hidro-sulphuret of lime. The carburetted
hidrogen, being left more or less pure, is conveyed through the pipe k, into
the gasometer, fig. 3. The communication of the purifier, fig. 2, with the
gasometer, is made by means of the well-known water-valve l, placed so
that the communicating tube k, may be easily removed at pleasure—m, is a
cock for drawing off the tar, &c. n, a gauge-cock for ascertaining the height
of the liquid in the chamber d. The gasometer, fig. 3, the object of which is
to store up the gas, consists of two principal parts—namely, a large interior
vessel designed to contain the gas, and an outer cistern or vessel, of rather
greater capacity, in which the former is suspended, designed to contain the
water by which the gas is confined. The interior vessel which contains the
gas is suspended by chains or cords hung over pullies, to which weights are
attached, so as to nearly equipoise it. o is a pipe, which communicates with
the water-valve l, and by means of which the gas passes from the purifier,
fig. 2, into the gasometer. The upper end of this pipe is covered, in the
manner of a hood, by a cylindrical vessel p, open at bottom, but partially
immersed beneath the surface of the water contained in the outer cistern of
the gasometer, and perforated round near the lower edge with a number of
small holes. The gas displaces the water from this receiver p, and escapes
through the small holes, rising in bubbles through the water, so as to expose
a large surface to its action, that it may be properly washed, &c. After rising
through the water the gas enters the gasometer, which is suspended to move
up and down by the chains, pullies, and balance-weights, q. From the centre
of the gasometer a tube, r, descends, which includes a pipe, s, fixed
perpendicular from the bottom of the cistern. The fixed pipe r, forms a
guide to keep the gasometer always perpendicular. t is also an iron pipe
made fast in the centre of the inner vessel, and communicates with the
upright tube, s, in the outer vessel. This contrivance obliges the gas to pass
into the pipe t, whilst it also serves to keep the gasometer steady when
nearly out of the outer cistern.
When the operation commences, the gasometer is sunk down nearly to a
level with the surface of the water in the outer cistern, and is consequently
filled with water; but as the gas enters, it rises up to receive it. It is to be
noted, that the balance-weights q q, should not be quite so heavy as the
Page 48
gasometer, in order that some pressure may be exerted, to force the gas out
of the burners with a proper jet. The gas which issues from the retort enters
the purifier as stated already, and ascends the pipe o, into the vessel, p, from
which it displaces the water, and passes out at the small holes, as before
described, rising through the water into the gasometer, and raising it up: the
gas then passes away to the burners, u u. In this manner the process
proceeds until the whole of the volatile products of the coal in the retort is
evaporated. The use of the gasometer is, to equalize the emission of the gas
which comes from the retort more quickly at some time than others. When
this happens, the interior vessel rises up to receive it, and when the stream
from the retort diminishes, the weight of the gasometer expels its contents.
When the process is finished, the retort is suffered to cool, and its ground
stopper is then removed to replenish it with coal. The residue found in the
retort is coke. v v are cocks to let off any liquid that may collect in the pipe
o or t; for if the smallest portion of liquid were to obstruct the free passage
of the gas to the burners, the consequence would be, that the lights would
not burn steadily—they would, as it is called, dance, or become
extinguished. x is the main stop-cock which communicates with the burners
—these, of course, may be placed as convenience may require. z z are two
projecting parts in the top of the gasometer; they are intended to receive the
hood p, and the upper extremity of the pipe t, so as to allow the gasometer
to be wholly immersed into the cistern. The wheels or pullies of the
gasometer have a groove to allow the links of the chain to pass freely.
In this apparatus there is no provision made for the unequal pressure which
the gas suffers, accordingly as the gasometer is more or less immersed in
water. It will be observed that, in this apparatus, the weight of the interior
vessel is constantly increasing, in proportion as it fills with gas, and rises
out of the water, and consequently, if a constant, uniform, counterpoising
weight, equal only to that of the gasometer in the first moment of its rise, be
employed, the gas becomes gradually more and more compressed by that
part of the weight of the gasometer which is not counterpoised, and if its
pressure or quantity be then estimated by the bulk which it occupies,
without making allowance for the increasing pressure, a material error must
arise, and this, in the large way, would give rise to insurmountable
difficulties with regard to the regulation of the size of the flames; which
could not be rendered uniform.
of the burners with a proper jet. The gas which issues from the retort enters
the purifier as stated already, and ascends the pipe o, into the vessel, p, from
which it displaces the water, and passes out at the small holes, as before
described, rising through the water into the gasometer, and raising it up: the
gas then passes away to the burners, u u. In this manner the process
proceeds until the whole of the volatile products of the coal in the retort is
evaporated. The use of the gasometer is, to equalize the emission of the gas
which comes from the retort more quickly at some time than others. When
this happens, the interior vessel rises up to receive it, and when the stream
from the retort diminishes, the weight of the gasometer expels its contents.
When the process is finished, the retort is suffered to cool, and its ground
stopper is then removed to replenish it with coal. The residue found in the
retort is coke. v v are cocks to let off any liquid that may collect in the pipe
o or t; for if the smallest portion of liquid were to obstruct the free passage
of the gas to the burners, the consequence would be, that the lights would
not burn steadily—they would, as it is called, dance, or become
extinguished. x is the main stop-cock which communicates with the burners
—these, of course, may be placed as convenience may require. z z are two
projecting parts in the top of the gasometer; they are intended to receive the
hood p, and the upper extremity of the pipe t, so as to allow the gasometer
to be wholly immersed into the cistern. The wheels or pullies of the
gasometer have a groove to allow the links of the chain to pass freely.
In this apparatus there is no provision made for the unequal pressure which
the gas suffers, accordingly as the gasometer is more or less immersed in
water. It will be observed that, in this apparatus, the weight of the interior
vessel is constantly increasing, in proportion as it fills with gas, and rises
out of the water, and consequently, if a constant, uniform, counterpoising
weight, equal only to that of the gasometer in the first moment of its rise, be
employed, the gas becomes gradually more and more compressed by that
part of the weight of the gasometer which is not counterpoised, and if its
pressure or quantity be then estimated by the bulk which it occupies,
without making allowance for the increasing pressure, a material error must
arise, and this, in the large way, would give rise to insurmountable
difficulties with regard to the regulation of the size of the flames; which
could not be rendered uniform.
Page 49
Suppose the cistern or exterior vessel full of water, and the gasometer partly
filled with gas and partly with water, it is evident that the balance-weight
may be so adjusted, as to occasion an exact equilibrium, so that the external
air shall not tend to enter into the gasometer nor the gas to escape from it;
and in this case the water will stand exactly at the same level both within
the gasometer and within the outer cistern. On the contrary, if the balance-
weights be diminished, the gasometer will then press downwards from its
own gravity, and the water will stand lower in the gasometer than it does in
the cistern; in this case, the included air or gas will suffer a degree of
compression above that experienced by the external air, exactly
proportioned to the weight of a column of water, equal to the difference of
the external and internal surfaces of the water.
To compensate for this increasing weight of the gasometer, and render a
scale of equal graduations accurate, some have ingeniously adopted the plan
of a spiral pulley to the chain, which has the effect of gradually avoiding the
evil, but the best way of accomplishing it will be stated hereafter.
With regard to the philosophy or the production of coal-gas, it proves that
pit-coal contains solid hidrogen, carbon, and oxigen. When the intensity of
the heat has reached a certain degree, a part of the carbon unites with part of
the oxigen and produces carbonic acid, which by means of caloric is melted
into the gazeous state and forms carbonic acid gas; at the same time, part of
the hidrogen of the coal combines with another portion of carbon and
caloric, and forms the carburetted hidrogen gas, which varies considerably
in its constitution, according to the circumstances under which it is
produced; a portion of olifiant gas, carbonic oxid, hidrogen, and
sulphuretted hidrogen, is also produced during the process. The quantities
of these products vary according to the nature of the coal employed in the
process.
Pit-coal is not the only substance which affords carburetted hydrogen; this
gazeous fluid may be obtained in a great variety of ways, and with very
considerable differences in specific gravity and proportion of ingredients.
It is found plentifully native or ready formed on the surface of stagnant
waters, marshes, wet ditches, &c. through which, if examined closely, large
filled with gas and partly with water, it is evident that the balance-weight
may be so adjusted, as to occasion an exact equilibrium, so that the external
air shall not tend to enter into the gasometer nor the gas to escape from it;
and in this case the water will stand exactly at the same level both within
the gasometer and within the outer cistern. On the contrary, if the balance-
weights be diminished, the gasometer will then press downwards from its
own gravity, and the water will stand lower in the gasometer than it does in
the cistern; in this case, the included air or gas will suffer a degree of
compression above that experienced by the external air, exactly
proportioned to the weight of a column of water, equal to the difference of
the external and internal surfaces of the water.
To compensate for this increasing weight of the gasometer, and render a
scale of equal graduations accurate, some have ingeniously adopted the plan
of a spiral pulley to the chain, which has the effect of gradually avoiding the
evil, but the best way of accomplishing it will be stated hereafter.
With regard to the philosophy or the production of coal-gas, it proves that
pit-coal contains solid hidrogen, carbon, and oxigen. When the intensity of
the heat has reached a certain degree, a part of the carbon unites with part of
the oxigen and produces carbonic acid, which by means of caloric is melted
into the gazeous state and forms carbonic acid gas; at the same time, part of
the hidrogen of the coal combines with another portion of carbon and
caloric, and forms the carburetted hidrogen gas, which varies considerably
in its constitution, according to the circumstances under which it is
produced; a portion of olifiant gas, carbonic oxid, hidrogen, and
sulphuretted hidrogen, is also produced during the process. The quantities
of these products vary according to the nature of the coal employed in the
process.
Pit-coal is not the only substance which affords carburetted hydrogen; this
gazeous fluid may be obtained in a great variety of ways, and with very
considerable differences in specific gravity and proportion of ingredients.
It is found plentifully native or ready formed on the surface of stagnant
waters, marshes, wet ditches, &c. through which, if examined closely, large
Page 50
bubbles will be seen to rise in hot weather, and may be increased at pleasure
by stirring the bottom or mud with a stick.
In close still evenings if a lighted candle is held over the surface, flashes of
blue lambent flame may sometimes be perceived spreading to a
considerable distance. All that is not fabulous concerning the ignis fatuus is
probably derived from this source. This species of gas is termed for
distinction the carburetted hydrogen of marshes. In the purest form in which
it can be collected it is mixed with about 20 per cent. of azot or nitrogen.
To procure the gas for the purpose of philosophical amusement, fill a wide-
mouthed bottle with the water of the ditch, and keep it inverted therein with
a large funnel in its neck, then with a stick stir the mud at the bottom just
under the funnel, so as to cause the bubbles of air which rise from the mud
to enter into the bottle; when by thus stirring the mud in various places, the
air may be catched in the bottle.
Carburetted hidrogen gas is also given out very abundantly by all kinds of
vegetable matter when subjected to a scorching heat sufficient to
decompose them. When heated in close vessels much more gas is obtained
than when burnt in the open air. If moistened charcoal be put into an earthen
retort and heat be applied till the retort becomes ignited; gas will be
evolved, consisting partly of carbonic acid, and partly of carburetted
hidrogen. A gas of similar properties is obtained by causing steam to pass
through a tube filled with red-hot charcoal; by passing spirit of wine, or
camphor, through red-hot tubes; by distilling oils, wood, bones, wax and
tallow, or any animal or vegetable body whatever.
Indeed it would be endless to enumerate the various sources of this gazeous
fluid. A most curious variety of carburetted hidrogen gas has been
discovered by the associated Dutch chemists (Van Dieman, Troostwyck,
and others) which is procured from ether or alcohol, and has the remarkable
property of generating a heavy oil when in contact with chlorine gas. Hence
it has been termed oily carburetted hidrogen, or olifiant gas—it consists of
carburetted hydrogen, supersaturated with carbon. The oil generated is
heavier than water, whitish, and semi-transparent. By keeping, it becomes
yellow and limpid; its smell is highly fragrant and penetrating—its taste
somewhat sweet—it is partly soluble in water, imparting to it, its peculiar
by stirring the bottom or mud with a stick.
In close still evenings if a lighted candle is held over the surface, flashes of
blue lambent flame may sometimes be perceived spreading to a
considerable distance. All that is not fabulous concerning the ignis fatuus is
probably derived from this source. This species of gas is termed for
distinction the carburetted hydrogen of marshes. In the purest form in which
it can be collected it is mixed with about 20 per cent. of azot or nitrogen.
To procure the gas for the purpose of philosophical amusement, fill a wide-
mouthed bottle with the water of the ditch, and keep it inverted therein with
a large funnel in its neck, then with a stick stir the mud at the bottom just
under the funnel, so as to cause the bubbles of air which rise from the mud
to enter into the bottle; when by thus stirring the mud in various places, the
air may be catched in the bottle.
Carburetted hidrogen gas is also given out very abundantly by all kinds of
vegetable matter when subjected to a scorching heat sufficient to
decompose them. When heated in close vessels much more gas is obtained
than when burnt in the open air. If moistened charcoal be put into an earthen
retort and heat be applied till the retort becomes ignited; gas will be
evolved, consisting partly of carbonic acid, and partly of carburetted
hidrogen. A gas of similar properties is obtained by causing steam to pass
through a tube filled with red-hot charcoal; by passing spirit of wine, or
camphor, through red-hot tubes; by distilling oils, wood, bones, wax and
tallow, or any animal or vegetable body whatever.
Indeed it would be endless to enumerate the various sources of this gazeous
fluid. A most curious variety of carburetted hidrogen gas has been
discovered by the associated Dutch chemists (Van Dieman, Troostwyck,
and others) which is procured from ether or alcohol, and has the remarkable
property of generating a heavy oil when in contact with chlorine gas. Hence
it has been termed oily carburetted hidrogen, or olifiant gas—it consists of
carburetted hydrogen, supersaturated with carbon. The oil generated is
heavier than water, whitish, and semi-transparent. By keeping, it becomes
yellow and limpid; its smell is highly fragrant and penetrating—its taste
somewhat sweet—it is partly soluble in water, imparting to it, its peculiar
Page 51
smell. A portion of this gas always accompanies the common carburetted
hidrogen obtained from coal, and those sorts of coal that afford the largest
quantity of it are best suited for the production of gas-light.
The nature of carburetted hidrogen obtained from coal varies considerably
according to the conditions under which it is obtained. The first part is
always much heavier than the last, though still lighter than common air, and
holds in solution a portion of oil, for on standing for some time over water
it becomes lighter, and is found to require less oxygen for saturation than
before. The oil which it held suspended, then becomes precipitated. The
average specific gravity of the first and last gas mixed, which may be taken
as an average of the whole specific gravity is to that of common air as 2 to 3
—112lb. of common cannel coal produce at its minimum, from 350 to 360
cubic feet of carburetted hidrogen gas; but the same quantity of the best
Newcastle coal, that is to say, such as coke, which, when laid on the fire
readily undergoes a kind of semi-fusion, and sends out brilliant streams of
flame, produces upon an average from 300 to 360 cubic feet of this gazeous
fluid, besides a large portion of sulphuretted hidrogen, carbonic oxid and
carbonic acid. Half a cubic foot of this carburetted hidrogen, fresh prepared,
that is to say, holding in solution or suspension, a portion of the essential
oil, which is generated during the evolution of the gas, is equal in
illuminating power to from 170 to 180 grains of tallow, (being the quantity
consumed by a candle six to the pound in one hour.) Now, one pound
avoirdupoise is equal to 7000 grains, and consequently one pound of
candles of six in the pound, burning one at a time in succession, would last
(if we take 175 grains of tallow to be consumed in an hour) 7000 175
= 40
hours. To produce the same light we must burn one half of a cubic foot of
coal-gas per hour; therefore, one-half multiplied by forty hours is equal to
twenty cubic feet of gas in 40 hours, consequently equal to one pound of
candles, six to the pound, provided they were burnt one after another. One
hundred and twelve pounds of cannel-coal, produce, at its minimum, three
hundred and fifty cubic feet of gas; and are equal to three hundred and fifty,
divided by twenty, which last is equivalent to one pound of tallow, making
one hundred and twelve pounds of cannel-coal, equal to 350 20
= 171⁄2lbs. of
tallow. Further, one hundred and twelve pounds of cannel-coal, divided by
hidrogen obtained from coal, and those sorts of coal that afford the largest
quantity of it are best suited for the production of gas-light.
The nature of carburetted hidrogen obtained from coal varies considerably
according to the conditions under which it is obtained. The first part is
always much heavier than the last, though still lighter than common air, and
holds in solution a portion of oil, for on standing for some time over water
it becomes lighter, and is found to require less oxygen for saturation than
before. The oil which it held suspended, then becomes precipitated. The
average specific gravity of the first and last gas mixed, which may be taken
as an average of the whole specific gravity is to that of common air as 2 to 3
—112lb. of common cannel coal produce at its minimum, from 350 to 360
cubic feet of carburetted hidrogen gas; but the same quantity of the best
Newcastle coal, that is to say, such as coke, which, when laid on the fire
readily undergoes a kind of semi-fusion, and sends out brilliant streams of
flame, produces upon an average from 300 to 360 cubic feet of this gazeous
fluid, besides a large portion of sulphuretted hidrogen, carbonic oxid and
carbonic acid. Half a cubic foot of this carburetted hidrogen, fresh prepared,
that is to say, holding in solution or suspension, a portion of the essential
oil, which is generated during the evolution of the gas, is equal in
illuminating power to from 170 to 180 grains of tallow, (being the quantity
consumed by a candle six to the pound in one hour.) Now, one pound
avoirdupoise is equal to 7000 grains, and consequently one pound of
candles of six in the pound, burning one at a time in succession, would last
(if we take 175 grains of tallow to be consumed in an hour) 7000 175
= 40
hours. To produce the same light we must burn one half of a cubic foot of
coal-gas per hour; therefore, one-half multiplied by forty hours is equal to
twenty cubic feet of gas in 40 hours, consequently equal to one pound of
candles, six to the pound, provided they were burnt one after another. One
hundred and twelve pounds of cannel-coal, produce, at its minimum, three
hundred and fifty cubic feet of gas; and are equal to three hundred and fifty,
divided by twenty, which last is equivalent to one pound of tallow, making
one hundred and twelve pounds of cannel-coal, equal to 350 20
= 171⁄2lbs. of
tallow. Further, one hundred and twelve pounds of cannel-coal, divided by
Page 52
seventeen and a half of tallow make six and four-tenths of cannel-coal,
equal to one pound of tallow.
With regard to Newcastle coals[17], it may be stated that one chaldron of
Wall’s-End coal may be made to produce in the large way upwards of
11,000 cubic feet of crude gas; which, when properly purified, diminishes
to nearly 10,000 cubic feet.
[17] One chaldron of Newcastle coal weighs from 2850 to upwards of 2978lb.
The production of carburetted hydrogen, both with regard to quantity and
quality from the same kind of coal depends much upon the degree of
temperature employed in the distillatory process. If the tar and oil produced
during the evolution of the gas in its nascent state, be made to come in
contact with the sides of the red hot retorts, or if it be made to pass through
an iron cylinder or other vessel heated red hot, a large portion becomes
decomposed into carburetted hydrogen gas and olifiant gas, and thus a
much larger quantity of gas is produced than would be obtained without
such precaution from the same quantity of coal.[18]
[18] One pound of coal-tar produces 15 cubic feet of carburetted hidrogen abounding in
olifiant gas.
The distillation of the coal, (if gas be the chief object) should therefore not
be carried on too rapidly. Most of the retorts used in the large way, are
calculated for containing about one hundred weight of coal, and in general,
when previously heated, produce from two and one-half to three cubic feet
of gas, in four hours for each pound of coal they contain; but when the layer
of coals in them does not exceed four inches in depth, three and one-half to
four feet of gas may be obtained in the same time.
The retorts best calculated for large gas-light works are seven or eight foot
long (without the mouth-piece) and twelve inches in diameter, tapering
down to ten inches—if they are larger the coal which they contain cannot be
heated properly. The advantages that may be derived from the
circumstances before stated are of greater value in the gas-light
manufacture than is often imagined, and the quantity as well as the quality
of the gas is very much influenced by such circumstances. If coal be
distilled with a very low red heat scarcely observable by daylight, the gas
produced gives a feeble light—if the temperature be increased so that the
equal to one pound of tallow.
With regard to Newcastle coals[17], it may be stated that one chaldron of
Wall’s-End coal may be made to produce in the large way upwards of
11,000 cubic feet of crude gas; which, when properly purified, diminishes
to nearly 10,000 cubic feet.
[17] One chaldron of Newcastle coal weighs from 2850 to upwards of 2978lb.
The production of carburetted hydrogen, both with regard to quantity and
quality from the same kind of coal depends much upon the degree of
temperature employed in the distillatory process. If the tar and oil produced
during the evolution of the gas in its nascent state, be made to come in
contact with the sides of the red hot retorts, or if it be made to pass through
an iron cylinder or other vessel heated red hot, a large portion becomes
decomposed into carburetted hydrogen gas and olifiant gas, and thus a
much larger quantity of gas is produced than would be obtained without
such precaution from the same quantity of coal.[18]
[18] One pound of coal-tar produces 15 cubic feet of carburetted hidrogen abounding in
olifiant gas.
The distillation of the coal, (if gas be the chief object) should therefore not
be carried on too rapidly. Most of the retorts used in the large way, are
calculated for containing about one hundred weight of coal, and in general,
when previously heated, produce from two and one-half to three cubic feet
of gas, in four hours for each pound of coal they contain; but when the layer
of coals in them does not exceed four inches in depth, three and one-half to
four feet of gas may be obtained in the same time.
The retorts best calculated for large gas-light works are seven or eight foot
long (without the mouth-piece) and twelve inches in diameter, tapering
down to ten inches—if they are larger the coal which they contain cannot be
heated properly. The advantages that may be derived from the
circumstances before stated are of greater value in the gas-light
manufacture than is often imagined, and the quantity as well as the quality
of the gas is very much influenced by such circumstances. If coal be
distilled with a very low red heat scarcely observable by daylight, the gas
produced gives a feeble light—if the temperature be increased so that the
Page 53
distillatory vessel is of a dull redness, the light is more brilliant and of a
better colour—if a bright or cherry-red heat be employed the gas produced,
burns with a brilliant white flame, and if the heat be increased so far that the
retort is almost white hot, and consequently in danger of melting, the gas
given out, has little illuminating power, and burns with a clear blueish
flame;[19] or if the coal abounds in pyrites or sulphuret of iron, as is
sometimes the case with Newcastle coal, a large quantity of sulphuretted
hidrogen is likewise evolved, which although it increases the illuminating
power of the coal-gas, has the capital disadvantage, of producing an
intolerable suffocating odour, when the gas is burnt which is particularly
perceptible in low rooms illuminated with such gas.
[19] It is chiefly a mixture of carbonic oxid, and hydrogen gas.
These observations also apply to the distillation of tar, which when distilled
either in a vaporous or nascent state, during its first production from coal in
the ordinary process, or if it be submitted to a second distillation, mingled
with a fresh portion of pit-coal, a practice usually had recourse to when this
product cannot be disposed of more advantageously. The best depth of coal
in the retort for procuring excellent gas, and at the same time for yielding
the greatest quantity from the same weight in the shortest possible time, is
about six inches.
The brightness of the coal-gas flame is rather diminished when the gas has
been long kept over water, and hence for illumination it should be used as
soon as prepared, but of course properly purified.
The quantity of gas taken up by water is affected by temperature, because
the temperature increases its elasticity; the quantity of gas absorbed,
diminishes as the temperature increases, and increases as the temperature
diminishes. 1⁄27 part of its own bulk of pure coal-gas is absorbed by the
water over which it is confined in the gazometer.
The chemical constitution of this gazeous fluid is best ascertained by
burning it in a vessel of oxygen gas, over lime-water in a pneumatic
reservoir, by means of a bladder and bent brass pipe. Two products are then
obtained, viz. water and carbonic acid. That water is produced, may be
shown by burning a very small stream of the gas in a long funnel-shaped
better colour—if a bright or cherry-red heat be employed the gas produced,
burns with a brilliant white flame, and if the heat be increased so far that the
retort is almost white hot, and consequently in danger of melting, the gas
given out, has little illuminating power, and burns with a clear blueish
flame;[19] or if the coal abounds in pyrites or sulphuret of iron, as is
sometimes the case with Newcastle coal, a large quantity of sulphuretted
hidrogen is likewise evolved, which although it increases the illuminating
power of the coal-gas, has the capital disadvantage, of producing an
intolerable suffocating odour, when the gas is burnt which is particularly
perceptible in low rooms illuminated with such gas.
[19] It is chiefly a mixture of carbonic oxid, and hydrogen gas.
These observations also apply to the distillation of tar, which when distilled
either in a vaporous or nascent state, during its first production from coal in
the ordinary process, or if it be submitted to a second distillation, mingled
with a fresh portion of pit-coal, a practice usually had recourse to when this
product cannot be disposed of more advantageously. The best depth of coal
in the retort for procuring excellent gas, and at the same time for yielding
the greatest quantity from the same weight in the shortest possible time, is
about six inches.
The brightness of the coal-gas flame is rather diminished when the gas has
been long kept over water, and hence for illumination it should be used as
soon as prepared, but of course properly purified.
The quantity of gas taken up by water is affected by temperature, because
the temperature increases its elasticity; the quantity of gas absorbed,
diminishes as the temperature increases, and increases as the temperature
diminishes. 1⁄27 part of its own bulk of pure coal-gas is absorbed by the
water over which it is confined in the gazometer.
The chemical constitution of this gazeous fluid is best ascertained by
burning it in a vessel of oxygen gas, over lime-water in a pneumatic
reservoir, by means of a bladder and bent brass pipe. Two products are then
obtained, viz. water and carbonic acid. That water is produced, may be
shown by burning a very small stream of the gas in a long funnel-shaped
Page 54
tube open at both ends. The formation of carbonic acid is evinced, by the
copious precipitation of the lime-water in the foregoing experiment.
If carburetted hydrogen be mixed with a sufficient quantity of oxygen gas
or common air and fired by the electric spark, or by any other method, an
explosion takes place more or less violent according to the quantity of
carbonaceous matter condensed in the hydrocarbonat; and the remaining
gas consists of carbonic acid, together with any unconsumed gas, or excess
of oxygen, whilst the water condenses in drops on the sides of the vessel. A
few cubic inches of the mixed airs is as much as can be conveniently
managed at a single explosion; and when any portion of olefiant gas is
present, even this quantity will endanger very thick glass jars. A very vivid
red flame appears at the moment of the explosion, and a great enlargement
takes place in an instant, after which the bulk is suddenly reduced to much
less than the original quantity. When the carbonic acid is absorbed by lime-
water, if the gasses have been properly proportioned, no gazeous residue is
left, except accidental impurities. Though carburetted hydrogen gas, is
sometimes naturally produced in coal-mines, and occasionally mixes with
common air, producing dreadful explosions, yet when coal-gas is mixed
with common air, it does not explode unless the gas be to the air as 1 to 10
nearly. Such are the leading chemical habitudes of this gazeous product.
The varieties of carburetted hydrogen gas all agree in being inflammable;
but they possess this property in various degrees, as is evinced by the
variable brightness of the flame which they yield when set on fire.
“Messrs. Sobolewsky and Horrer, of St. Petersburgh, have employed wood
for the purpose of producing carburetted hydrogen gas. The pyroligneous
acid obtained in this operation, when freed from the empyreumatic oil with
which it is mixed, becomes acetous acid, and is applicable to all the uses of
vinegar. A cubic cord of wood equal to 2.133 French metres (a metre being
rather more than an English yard), yields 255 Paris pounds of charcoal, and
70 buckets of acid. The latter gives 30 pounds of tar, after the extraction of
it 50 buckets of good vinegar remain. The same quantity of wood furnishes
50,000 cubic feet of gas, sufficient for the supply of 4000 lamps for five
hours.”[20]
[20] See Repository of Arts, Vol. XI. No. 36, p. 341.
copious precipitation of the lime-water in the foregoing experiment.
If carburetted hydrogen be mixed with a sufficient quantity of oxygen gas
or common air and fired by the electric spark, or by any other method, an
explosion takes place more or less violent according to the quantity of
carbonaceous matter condensed in the hydrocarbonat; and the remaining
gas consists of carbonic acid, together with any unconsumed gas, or excess
of oxygen, whilst the water condenses in drops on the sides of the vessel. A
few cubic inches of the mixed airs is as much as can be conveniently
managed at a single explosion; and when any portion of olefiant gas is
present, even this quantity will endanger very thick glass jars. A very vivid
red flame appears at the moment of the explosion, and a great enlargement
takes place in an instant, after which the bulk is suddenly reduced to much
less than the original quantity. When the carbonic acid is absorbed by lime-
water, if the gasses have been properly proportioned, no gazeous residue is
left, except accidental impurities. Though carburetted hydrogen gas, is
sometimes naturally produced in coal-mines, and occasionally mixes with
common air, producing dreadful explosions, yet when coal-gas is mixed
with common air, it does not explode unless the gas be to the air as 1 to 10
nearly. Such are the leading chemical habitudes of this gazeous product.
The varieties of carburetted hydrogen gas all agree in being inflammable;
but they possess this property in various degrees, as is evinced by the
variable brightness of the flame which they yield when set on fire.
“Messrs. Sobolewsky and Horrer, of St. Petersburgh, have employed wood
for the purpose of producing carburetted hydrogen gas. The pyroligneous
acid obtained in this operation, when freed from the empyreumatic oil with
which it is mixed, becomes acetous acid, and is applicable to all the uses of
vinegar. A cubic cord of wood equal to 2.133 French metres (a metre being
rather more than an English yard), yields 255 Paris pounds of charcoal, and
70 buckets of acid. The latter gives 30 pounds of tar, after the extraction of
it 50 buckets of good vinegar remain. The same quantity of wood furnishes
50,000 cubic feet of gas, sufficient for the supply of 4000 lamps for five
hours.”[20]
[20] See Repository of Arts, Vol. XI. No. 36, p. 341.
Page 55
UTILITY
OF THE
GAS-LIGHT ILLUMINATION,
WITH REGARD TO
PUBLIC AND PRIVATE ECONOMY.
From what has been stated in the preceding pages it becomes obvious, that
a substance yielding an artificial light may be obtained from common coal
in immense quantities. The attempt to derive advantage from so valuable a
discovery is surely no idle speculation. Let us therefore now consider to
what objects of public and private utility this mode of procuring light may
be applied with effect. It is obvious that coal-gas may be preserved in a
reservoir for any length of time and that it may be conveyed by means of
tubes to any distance flowing equably and regularly like water. Those,
indeed, who have not seen the contrivance will find it difficult to imagine
with what ease it is managed. The gas may be distributed through an
infinity of ramifications of tubes with the utmost facility. Near the
termination of each of the tubes through which it flows, it is confined by a
valve or stop-cock, upon turning which, when required to be lighted, it
flows out in an equable stream and ascends by its specific levity. There is
nothing to indicate its presence; no noise at the opening of the stop-cock or
valve—no disturbance in the transparency of the atmosphere—it instantly
bursts on the approach of a lighted taper, into a brilliant, noiseless, steady
and beautiful flame. Its purity is attested by its not blacking or soiling in the
least degree the metallic orifice from which it issues, nor even a sheet of
white paper, or polished surface brought in contact with it. There is no
escape of combustible matter unconsumed, which is so great a nuisance in
all our common lights. The products of the combustion are water and
carbonic acid gas[21]. The accurate and elegant experiments of Dr. W. Henry
have shewn in the most satisfactory manner, that considerably less carbonic
acid is produced by the flame of coal-gas, than by that of oil, tallow, or
wax[22], which sufficiently refutes the absurd notions that have been
circulated respecting the pernicious effects of gas-lights. But if the gas from
Newcastle coal is badly prepared, or not deprived of the portion of
sulphuretted hydrogen, which it usually contains, it then emits fiery sparks
and produces a portion of sulphureous acid by virtue of the union of the
OF THE
GAS-LIGHT ILLUMINATION,
WITH REGARD TO
PUBLIC AND PRIVATE ECONOMY.
From what has been stated in the preceding pages it becomes obvious, that
a substance yielding an artificial light may be obtained from common coal
in immense quantities. The attempt to derive advantage from so valuable a
discovery is surely no idle speculation. Let us therefore now consider to
what objects of public and private utility this mode of procuring light may
be applied with effect. It is obvious that coal-gas may be preserved in a
reservoir for any length of time and that it may be conveyed by means of
tubes to any distance flowing equably and regularly like water. Those,
indeed, who have not seen the contrivance will find it difficult to imagine
with what ease it is managed. The gas may be distributed through an
infinity of ramifications of tubes with the utmost facility. Near the
termination of each of the tubes through which it flows, it is confined by a
valve or stop-cock, upon turning which, when required to be lighted, it
flows out in an equable stream and ascends by its specific levity. There is
nothing to indicate its presence; no noise at the opening of the stop-cock or
valve—no disturbance in the transparency of the atmosphere—it instantly
bursts on the approach of a lighted taper, into a brilliant, noiseless, steady
and beautiful flame. Its purity is attested by its not blacking or soiling in the
least degree the metallic orifice from which it issues, nor even a sheet of
white paper, or polished surface brought in contact with it. There is no
escape of combustible matter unconsumed, which is so great a nuisance in
all our common lights. The products of the combustion are water and
carbonic acid gas[21]. The accurate and elegant experiments of Dr. W. Henry
have shewn in the most satisfactory manner, that considerably less carbonic
acid is produced by the flame of coal-gas, than by that of oil, tallow, or
wax[22], which sufficiently refutes the absurd notions that have been
circulated respecting the pernicious effects of gas-lights. But if the gas from
Newcastle coal is badly prepared, or not deprived of the portion of
sulphuretted hydrogen, which it usually contains, it then emits fiery sparks
and produces a portion of sulphureous acid by virtue of the union of the
Page 56
oxygen of the air with the sulphur dissolved in the gas, the consequence of
which is, a suffocating odour, which is particularly observable in the higher
stratum of the air of apartments in which the gas is burnt. Such gas likewise
tarnishes all metallic bodies—it discolours the paintings effected with
metallic oxids, and always produces a suffocating odour very noxious to
health. It is freed from the sulphuretted hydrogen and may be rendered fit
for illumination by passing it repeatedly through very dilute solutions of
sub-acetate of lead, green sulphate of iron, quicklime and water, or hyper-
oxymuriate of lime.
[21] The water (which passes off in imperceptible vapour) is generated by part of the
oxygen of the air uniting with part of the hydrogen, which forms the great bulk of the coal-
gas: and the carbonic acid gas is produced by the union of another portion of the oxygen
uniting with the smaller portion of carbon, which is the other component part of the coal-
gas.
[22] 100 Cubic inches of carburetted hydrogen from coal, require for burning 220 cubic
inches of oxygen and produce 100 cubic inches of carbonic acid—100 cubic inches of the
same gas obtained from wax, require for burning 280 cubic inches of oxygen and produce
137 cubic inches of carbonic acid—100 cubic inches of the same gas procured from lamp-
oil, require 190 cubic inches of oxygen for burning, and produce 124 cubic inches of
carbonic acid.
The following lines relating to the salubrity of the gas-light illumination are copied from
Mr. Lee’s evidence in the House of Commons, when examined on that subject.
Question—“Is the health of your manufacturers at all affected by the use of gas?—Answer
—Not in the least, or I would not have adopted it. I believe I explained to the Committee,
that I used the gas-lights in my own house first.”
Q. “You have not seen the smallest alteration in the health of your workmen?—A. Not in
the least, for had I seen it, it would have been a fatal objection to it.”
Q. “And you say the same in regard to the use of the gas-lights in your own family?—A.
Certainly I do.”
As to the brilliancy of the flame, an appeal may be made to every one who
has witnessed the gas-light illumination, whether it be not superior to the
best wax candle-light, or the light of Argand’s lamps.
It may be described as a rich compact flame, burning with a white and
agreeable light. It is also perfectly steady, when the flame is limited to a
moderate size: in large masses, it is subject to that undulation which is
common to it with all flames of certain dimensions, and is caused by the
agitation of the surrounding atmosphere. The gas flame is entirely free from
smell. The coal-gas itself certainly has a disagreeable foetid odour before it
which is, a suffocating odour, which is particularly observable in the higher
stratum of the air of apartments in which the gas is burnt. Such gas likewise
tarnishes all metallic bodies—it discolours the paintings effected with
metallic oxids, and always produces a suffocating odour very noxious to
health. It is freed from the sulphuretted hydrogen and may be rendered fit
for illumination by passing it repeatedly through very dilute solutions of
sub-acetate of lead, green sulphate of iron, quicklime and water, or hyper-
oxymuriate of lime.
[21] The water (which passes off in imperceptible vapour) is generated by part of the
oxygen of the air uniting with part of the hydrogen, which forms the great bulk of the coal-
gas: and the carbonic acid gas is produced by the union of another portion of the oxygen
uniting with the smaller portion of carbon, which is the other component part of the coal-
gas.
[22] 100 Cubic inches of carburetted hydrogen from coal, require for burning 220 cubic
inches of oxygen and produce 100 cubic inches of carbonic acid—100 cubic inches of the
same gas obtained from wax, require for burning 280 cubic inches of oxygen and produce
137 cubic inches of carbonic acid—100 cubic inches of the same gas procured from lamp-
oil, require 190 cubic inches of oxygen for burning, and produce 124 cubic inches of
carbonic acid.
The following lines relating to the salubrity of the gas-light illumination are copied from
Mr. Lee’s evidence in the House of Commons, when examined on that subject.
Question—“Is the health of your manufacturers at all affected by the use of gas?—Answer
—Not in the least, or I would not have adopted it. I believe I explained to the Committee,
that I used the gas-lights in my own house first.”
Q. “You have not seen the smallest alteration in the health of your workmen?—A. Not in
the least, for had I seen it, it would have been a fatal objection to it.”
Q. “And you say the same in regard to the use of the gas-lights in your own family?—A.
Certainly I do.”
As to the brilliancy of the flame, an appeal may be made to every one who
has witnessed the gas-light illumination, whether it be not superior to the
best wax candle-light, or the light of Argand’s lamps.
It may be described as a rich compact flame, burning with a white and
agreeable light. It is also perfectly steady, when the flame is limited to a
moderate size: in large masses, it is subject to that undulation which is
common to it with all flames of certain dimensions, and is caused by the
agitation of the surrounding atmosphere. The gas flame is entirely free from
smell. The coal-gas itself certainly has a disagreeable foetid odour before it
Page 57
is burnt, so has the vapour of wax, oil, and tallow, as it comes from a lamp
or candle newly blown out. This concession proves nothing against the
flame of gas which is perfectly inodorous, a white handkerchief, passed
repeatedly through it and applied to the nose, excites no odour.
Another peculiar advantage of the gas flame is, that it may be applied in any
direction we please, as there is nothing to spill and the gas is propelled by a
certain force which is always the same, it will burn equally well in an
almost horizontal as in an upright position; and we can thus obviate two
great objections to all our artificial lights, that their least luminous end is
directed downwards where the light is generally most wanted, and that a
shade is cast below by the stand or support of the combustible matter.
The size, shape and intensity of the gas-flame may be regulated by simply
turning a stop-cock which supplies the gas to the burner. It may at
command be made to burn with an intensity sufficient to illuminate every
corner of a room, or so low and dim as barely to be perceived. It is
unnecessary to point out how valuable such lights may be in nurseries,
stables, warehouses, in the chambers of the sick, &c.
From the facility with which the gas-flame can be conveyed in any
direction, from the diversified application, size and shape which the flame
can be made to assume, there is no other kind of light so well calculated for
being made the subject of splendid illuminations.
Where lustres are required in the middle of a room, the best mode of
conducting the gas to the chandelier, is to pass the gas-pipe through the
ceiling from the room above, immediately over the lustre. This can be easily
done without injury to the apartment.
Where side-lights and chandeliers are required the tubes need never appear
in sight, but may be concealed in the wall or floor of the house. When
transparencies are wanted as decorations for halls, lobbies, &c. more than
light, recesses may be filled with different coloured media, or paintings, and
any intensity of light may be thrown on the object.
If a number of minute holes are made in the end of a gas pipe, it forms as
many jets de feu, which have a very brilliant appearance; these may
sometimes be placed in the focus of a parabolic reflector. In cases where the
or candle newly blown out. This concession proves nothing against the
flame of gas which is perfectly inodorous, a white handkerchief, passed
repeatedly through it and applied to the nose, excites no odour.
Another peculiar advantage of the gas flame is, that it may be applied in any
direction we please, as there is nothing to spill and the gas is propelled by a
certain force which is always the same, it will burn equally well in an
almost horizontal as in an upright position; and we can thus obviate two
great objections to all our artificial lights, that their least luminous end is
directed downwards where the light is generally most wanted, and that a
shade is cast below by the stand or support of the combustible matter.
The size, shape and intensity of the gas-flame may be regulated by simply
turning a stop-cock which supplies the gas to the burner. It may at
command be made to burn with an intensity sufficient to illuminate every
corner of a room, or so low and dim as barely to be perceived. It is
unnecessary to point out how valuable such lights may be in nurseries,
stables, warehouses, in the chambers of the sick, &c.
From the facility with which the gas-flame can be conveyed in any
direction, from the diversified application, size and shape which the flame
can be made to assume, there is no other kind of light so well calculated for
being made the subject of splendid illuminations.
Where lustres are required in the middle of a room, the best mode of
conducting the gas to the chandelier, is to pass the gas-pipe through the
ceiling from the room above, immediately over the lustre. This can be easily
done without injury to the apartment.
Where side-lights and chandeliers are required the tubes need never appear
in sight, but may be concealed in the wall or floor of the house. When
transparencies are wanted as decorations for halls, lobbies, &c. more than
light, recesses may be filled with different coloured media, or paintings, and
any intensity of light may be thrown on the object.
If a number of minute holes are made in the end of a gas pipe, it forms as
many jets de feu, which have a very brilliant appearance; these may
sometimes be placed in the focus of a parabolic reflector. In cases where the
Page 58
light is required to be thrown to a distance, other burners are constructed
upon the same principle as the Argand lamp, forming a cylinder of flame,
and admitting a current of air both to the inside and outside.
On comparing the flame of a gas-light with the flame of a candle whatever
its size may be, it appears just as yellow and dull as the flame of a common
lamp appears when compared with that of a lamp of Argand. The beautiful
whiteness of gas-light never fails to excite the surprize and admiration of
those who behold it for the first time.
A large edifice or manufactory lighted by gas, contrasted with one of the
same kind lighted by candles or lamps, resembles a street on the night of a
general illumination, compared with the glimmering light of its ordinary
parish lamps.
The intensity of one of the parish gas-light lamps, now exhibited in the
streets of this metropolis, will bear ample testimony of this assertion; the
light of the parish gas-lamps, is to the intensity of the parish oil lamps as 1
to 12.
One of the most obvious applications of the gas-light illumination
unquestionably consists in lighting streets, shops and houses; and let it be
observed that as this is found safe and economical, it proves all that the
most ardent friends of the gas-light system can desire. For in contending
with the common mode of lighting the streets and shops, the new lights
must beat out of the market the cheapest of all artificial lights; and as it has
succeeded in doing this it shews in the most satisfactory point of view, the
prodigious advantages of gas-lights when compared with the materials of
tallow and oil.
The original expence of laying the pipes for conveying the gas, together
with the cost of the machinery, is all that is required; the preparation of the
gas being itself a lucrative process, no doubt will pay all its expences
besides the interest of capital, and leave a surplus of profit.
Indeed the application of the coal-gas, as a substitute for tallow and oil, to
illuminate houses, shops, &c. is no longer problematical, a considerable
extent of this capital, together with numerous shops and houses being
already supplied with this species of light.[23]
upon the same principle as the Argand lamp, forming a cylinder of flame,
and admitting a current of air both to the inside and outside.
On comparing the flame of a gas-light with the flame of a candle whatever
its size may be, it appears just as yellow and dull as the flame of a common
lamp appears when compared with that of a lamp of Argand. The beautiful
whiteness of gas-light never fails to excite the surprize and admiration of
those who behold it for the first time.
A large edifice or manufactory lighted by gas, contrasted with one of the
same kind lighted by candles or lamps, resembles a street on the night of a
general illumination, compared with the glimmering light of its ordinary
parish lamps.
The intensity of one of the parish gas-light lamps, now exhibited in the
streets of this metropolis, will bear ample testimony of this assertion; the
light of the parish gas-lamps, is to the intensity of the parish oil lamps as 1
to 12.
One of the most obvious applications of the gas-light illumination
unquestionably consists in lighting streets, shops and houses; and let it be
observed that as this is found safe and economical, it proves all that the
most ardent friends of the gas-light system can desire. For in contending
with the common mode of lighting the streets and shops, the new lights
must beat out of the market the cheapest of all artificial lights; and as it has
succeeded in doing this it shews in the most satisfactory point of view, the
prodigious advantages of gas-lights when compared with the materials of
tallow and oil.
The original expence of laying the pipes for conveying the gas, together
with the cost of the machinery, is all that is required; the preparation of the
gas being itself a lucrative process, no doubt will pay all its expences
besides the interest of capital, and leave a surplus of profit.
Indeed the application of the coal-gas, as a substitute for tallow and oil, to
illuminate houses, shops, &c. is no longer problematical, a considerable
extent of this capital, together with numerous shops and houses being
already supplied with this species of light.[23]
Page 59
[23] The Liberty of Norton Falgate, as far as Bishopgate-street, is lighted with gas-light,
from the Chartered Company’s station at Norton Falgate; and gas-light pipes are laid from
that station as far as the west end of Cheapside, and in all the streets north of that great
thoroughfare.
In the West end of the Town, the main pipes for supplying the streets and houses with light
from the Gas-Light Company, extend through the most eligible parts; from their
Establishment in Peter-street, Westminster, along the line from Pall Mall to Temple-bar,
compleatly surrounding the parish of St. Martin’s in the Field. Main pipes are also placed
in the Hay-market, Coventry-street, Long-Acre, St. Martin’s-lane; and in the principal parts
of the parishes of St. James and St. Ann.
In the East end of the metropolis, the gas-light mains extend from Cornhill to St. Paul’s,
Wood-street, Fore-street, &c.—Consent has also been given to the incorporated Gas-Light
Company for laying their pipes in the parish of St. Stephen’s in the Field; St. Paul Covent-
garden; St. Mary-le-Strand; St. Clement Danes; St. George’s, Bloomsbury; St. Giles’s in
the Fields; St. Andrew’s, Holborn, above the bars; part of the parish of St. Mary-la-bonne;
besides several other districts, comprehending the whole of the city and suburbs of
Westminster.
Enough therefore, has been done to prove the possibility of lighting houses,
and streets, with gas, which would have been regarded twenty years ago as
an extravagant paradox.[24]
[24] I am informed by Mr. Clegg, the engineer of the Chartered Gas-Light Company,
under whose direction the new system of lighting is carried on, that the total length of pipe
laid down, as mains, in the streets of London amounts already to nearly 15 miles.
In the Eastern part of London, the same Company is engaged to lay their pipes in the
principal parts of Whitechapel, Spitalfields, St. Luke’s, and the adjoining neighbourhood.
One part of the city of London, extending from Temple-bar to the West end of Cheapside;
from Newgate-street to Holborn Bars, together with the intervening streets, is also
provided with pipes laid down by another gas-light association, who have opened a new
Establishment in Water-lane, Fleet-street, but are unconnected with the Chartered
Company. A third company is projected in Southwark, and a fourth in the Eastern district
of London, creating by a rivalry of interest, that laudable competition which always proves
beneficial to the public at large, and which cannot fail to accelerate the progress of this new
art of procuring light.
The Church of St. John the Evangelist in this metropolis has been
illuminated with gas-lights for upwards of two years: the lights employed in
this edifice is equal to 360 tallow candles eight to the pound. The avenues
to the House of Lords and House of Commons, Westminster-hall,
Westminster-bridge; the house and offices of the Speaker of the House of
Commons, the Mansion-house, and many other places, deserve to be
named, as having already adopted this species of illumination.
from the Chartered Company’s station at Norton Falgate; and gas-light pipes are laid from
that station as far as the west end of Cheapside, and in all the streets north of that great
thoroughfare.
In the West end of the Town, the main pipes for supplying the streets and houses with light
from the Gas-Light Company, extend through the most eligible parts; from their
Establishment in Peter-street, Westminster, along the line from Pall Mall to Temple-bar,
compleatly surrounding the parish of St. Martin’s in the Field. Main pipes are also placed
in the Hay-market, Coventry-street, Long-Acre, St. Martin’s-lane; and in the principal parts
of the parishes of St. James and St. Ann.
In the East end of the metropolis, the gas-light mains extend from Cornhill to St. Paul’s,
Wood-street, Fore-street, &c.—Consent has also been given to the incorporated Gas-Light
Company for laying their pipes in the parish of St. Stephen’s in the Field; St. Paul Covent-
garden; St. Mary-le-Strand; St. Clement Danes; St. George’s, Bloomsbury; St. Giles’s in
the Fields; St. Andrew’s, Holborn, above the bars; part of the parish of St. Mary-la-bonne;
besides several other districts, comprehending the whole of the city and suburbs of
Westminster.
Enough therefore, has been done to prove the possibility of lighting houses,
and streets, with gas, which would have been regarded twenty years ago as
an extravagant paradox.[24]
[24] I am informed by Mr. Clegg, the engineer of the Chartered Gas-Light Company,
under whose direction the new system of lighting is carried on, that the total length of pipe
laid down, as mains, in the streets of London amounts already to nearly 15 miles.
In the Eastern part of London, the same Company is engaged to lay their pipes in the
principal parts of Whitechapel, Spitalfields, St. Luke’s, and the adjoining neighbourhood.
One part of the city of London, extending from Temple-bar to the West end of Cheapside;
from Newgate-street to Holborn Bars, together with the intervening streets, is also
provided with pipes laid down by another gas-light association, who have opened a new
Establishment in Water-lane, Fleet-street, but are unconnected with the Chartered
Company. A third company is projected in Southwark, and a fourth in the Eastern district
of London, creating by a rivalry of interest, that laudable competition which always proves
beneficial to the public at large, and which cannot fail to accelerate the progress of this new
art of procuring light.
The Church of St. John the Evangelist in this metropolis has been
illuminated with gas-lights for upwards of two years: the lights employed in
this edifice is equal to 360 tallow candles eight to the pound. The avenues
to the House of Lords and House of Commons, Westminster-hall,
Westminster-bridge; the house and offices of the Speaker of the House of
Commons, the Mansion-house, and many other places, deserve to be
named, as having already adopted this species of illumination.
Page 60
Another advantageous application of the gas-light must be the supplying of
light-houses.
From the splendour and distinguishing forms which the gas-light flame is
capable of assuming, no light is better calculated for signal-lights than this.
By means of one single furnace as much gas might readily be procured as
would furnish a flame of sufficient intensity, during the longest winter
night, exceeding in brilliancy or intensity of light any light-house in Britain
or elsewhere.
If every light-house round this island were possessed of a gas-light furnace,
one-half part of the enormous expence which they at present require would
furnish a much more brilliant light. The cheapness of this light and its
efficacy for the purpose, would soon multiply the number of light-houses,
and thus most essentially contribute to the security of navigation on our
coast. The gas may be made to issue from tubes by long narrow slips, and a
surface of flame produced of any given dimensions, and free from all
smoke that would obscure the reflectors.
The ease with which the largest gas-light flame is instantly extinguished by
shutting the stop-cock, and the readiness with which a long line of gas
catches fire by applying a lighted taper to one extremity, are properties that
cannot fail to recommend it for the purposes of telegraphic communications
by night. Another application of the gas unquestionably might be the
lighting of barracks, arsenals, dock-yards, and other establishments where
much light is wanted in a small place.
The annual expence of lighting the barracks of Great Britain is said to fall
little short of 50,000l. a small part of which on the new plan, would supply
them with a much purer and safer light.
The uses of the gas-lights already enumerated must of themselves, justify us
in attaching great importance to the discovery, and if reduced to practice all
over the kingdom, would employ a large capital in a way the most
advantageous and productive. But the utility of this light will be almost
indefinitely increased to the use of private families. That such an
application is practicable, in all towns of Great Britain, is obvious, from
what has been done already, and that it would be highly economical and
ornamental, there can be little doubt.
light-houses.
From the splendour and distinguishing forms which the gas-light flame is
capable of assuming, no light is better calculated for signal-lights than this.
By means of one single furnace as much gas might readily be procured as
would furnish a flame of sufficient intensity, during the longest winter
night, exceeding in brilliancy or intensity of light any light-house in Britain
or elsewhere.
If every light-house round this island were possessed of a gas-light furnace,
one-half part of the enormous expence which they at present require would
furnish a much more brilliant light. The cheapness of this light and its
efficacy for the purpose, would soon multiply the number of light-houses,
and thus most essentially contribute to the security of navigation on our
coast. The gas may be made to issue from tubes by long narrow slips, and a
surface of flame produced of any given dimensions, and free from all
smoke that would obscure the reflectors.
The ease with which the largest gas-light flame is instantly extinguished by
shutting the stop-cock, and the readiness with which a long line of gas
catches fire by applying a lighted taper to one extremity, are properties that
cannot fail to recommend it for the purposes of telegraphic communications
by night. Another application of the gas unquestionably might be the
lighting of barracks, arsenals, dock-yards, and other establishments where
much light is wanted in a small place.
The annual expence of lighting the barracks of Great Britain is said to fall
little short of 50,000l. a small part of which on the new plan, would supply
them with a much purer and safer light.
The uses of the gas-lights already enumerated must of themselves, justify us
in attaching great importance to the discovery, and if reduced to practice all
over the kingdom, would employ a large capital in a way the most
advantageous and productive. But the utility of this light will be almost
indefinitely increased to the use of private families. That such an
application is practicable, in all towns of Great Britain, is obvious, from
what has been done already, and that it would be highly economical and
ornamental, there can be little doubt.
Page 61
By means of gas we may have a pure and agreeable light at command in
every room of our house, just as we have the command of water, with this
singular advantage, that these lights may burn for hours within an inch of
the most combustible substance without danger, because they neither can
burn down like a candle nor emit sparks. These properties make the gas-
lights a most desirable light on board our ships of war, where severe
regulations are necessary to prevent danger from fire, which after all are
frequently evaded. The gas-light might be used in the store-rooms, and even
in the powder magazine, and the captain would completely command the
supply of light by the possession of the key which opens and shuts the stop-
cock. A small apparatus which may be erected at a trifling expence would
be sufficient for that purpose.
In shops, counting-houses, and public offices, the advantages are a white
light, nearly equal to day-light, a warmth which almost supersedes the use
of fires, a total absence of smoke, smell, and vapour, and great economy of
labour.
The heat produced by gas-lights must be observed by every one who has
had an opportunity of attending to it in the most superficial manner, and the
reason why gas-lights produce more heat than oil or candle-light will not
appear strange to our chemical readers (and who is there now that does not
know something of chemistry?) when it is considered that the gas-light
flame condenses more air than the flame of oil and tallow, and consequently
must produce more heat.
The flame of gas may be produced in so large a surface, as to be applied to
heat the most spacious apartments as well as to light them.
If the gas is made to issue by a circular rim of about twelve inches diameter;
it forms a sort of an Argand lamp on a great scale, and it is manifest that a
circumference of three feet of flame will heat the air very rapidly, and with
such uniformity that we need no longer be exposed to the partial heating
occasioned by the strong draft of a large fire. A lamp of this description in
the centre of a large room, with a very small fire to secure a gradual renewal
of the air would enable us to enjoy the most healthful and agreeable
temperature.
every room of our house, just as we have the command of water, with this
singular advantage, that these lights may burn for hours within an inch of
the most combustible substance without danger, because they neither can
burn down like a candle nor emit sparks. These properties make the gas-
lights a most desirable light on board our ships of war, where severe
regulations are necessary to prevent danger from fire, which after all are
frequently evaded. The gas-light might be used in the store-rooms, and even
in the powder magazine, and the captain would completely command the
supply of light by the possession of the key which opens and shuts the stop-
cock. A small apparatus which may be erected at a trifling expence would
be sufficient for that purpose.
In shops, counting-houses, and public offices, the advantages are a white
light, nearly equal to day-light, a warmth which almost supersedes the use
of fires, a total absence of smoke, smell, and vapour, and great economy of
labour.
The heat produced by gas-lights must be observed by every one who has
had an opportunity of attending to it in the most superficial manner, and the
reason why gas-lights produce more heat than oil or candle-light will not
appear strange to our chemical readers (and who is there now that does not
know something of chemistry?) when it is considered that the gas-light
flame condenses more air than the flame of oil and tallow, and consequently
must produce more heat.
The flame of gas may be produced in so large a surface, as to be applied to
heat the most spacious apartments as well as to light them.
If the gas is made to issue by a circular rim of about twelve inches diameter;
it forms a sort of an Argand lamp on a great scale, and it is manifest that a
circumference of three feet of flame will heat the air very rapidly, and with
such uniformity that we need no longer be exposed to the partial heating
occasioned by the strong draft of a large fire. A lamp of this description in
the centre of a large room, with a very small fire to secure a gradual renewal
of the air would enable us to enjoy the most healthful and agreeable
temperature.
Page 62
From trials made on this subject, I am enabled to state, that three Argand’s
lamps, consuming five cubic feet of gas per hour, are sufficient to keep a
room 10 feet square at a temperature of 55° Fahr. when the air without
doors has a temperature of freezing.[25]
[25] Mr. Dalton’s method of ascertaining the comparative quantity or effects of heat
evolved during the combustion of different inflammable gases, and other substances
capable of burning with flame, as stated in his System of Chemistry, vol. I. p. 76, deserves
to be recommended to those who are more immediately interested in this subject. The
process, which is simple, easy, and accurate, is as follows:
Take a bladder of any size, (let us suppose for the sake of illustration, the bladder to hold or
to be equal in capacity to 30,000 grains of water,) and having furnished it with a stop-cock
and a small jet pipe, fill it with the combustible gas the heating power of which is to be
tried. Take also a tinned iron vessel with a concave bottom of the same capacity, pour into
it as much water as will make the vessel and water together equal to the above stated bulk
of water in the bladder, viz. 30,000 grains. This being done, set fire to the gas at the orifice
of the pipe, and bring the point of the flame under the bottom of the tinned vessel, and
suffer it to burn there, by squeezing the bladder till the whole of the gas is consumed. The
increase of temperature of the water in the tinned vessel being carefully noticed before and
after the experiment, gives very accurately the heating power of the given bulk of the
inflammable gas.
It was thus proved that—
Olefiant gas raises an equal volume of water 14°
Carburetted hidrogen, or coal gas 10
Carbonic oxid 4
Hidrogen 5
Spermaceti oil 10 grains burnt in a lamp raised 30,000 grains of water 5
Tallow 5
Wax 5,75
Oil of turpentine 3
Spirit of wine 2
In all processes of the arts where a moderate heat is wanted the gas-light
flame will be found very advantageous—even on a large scale this flame
may be used with profit. It possesses advantages which cannot be obtained
from flaming fuel, where much nicety is required; because no fuel can be
managed like the flame of coal-gas. For it is well known, that when too
little air be given to flaming fuel it produces no flame, but sooty vapour;
and if too much air be admitted to make those vapours break out into flame,
the heat is often too violent. It is a fact, that flame, when produced in great
quantity, and made to burn violently, by mixing with a proper portion of
fresh air, driving it on the subject, and throwing it into whirls and eddies,
lamps, consuming five cubic feet of gas per hour, are sufficient to keep a
room 10 feet square at a temperature of 55° Fahr. when the air without
doors has a temperature of freezing.[25]
[25] Mr. Dalton’s method of ascertaining the comparative quantity or effects of heat
evolved during the combustion of different inflammable gases, and other substances
capable of burning with flame, as stated in his System of Chemistry, vol. I. p. 76, deserves
to be recommended to those who are more immediately interested in this subject. The
process, which is simple, easy, and accurate, is as follows:
Take a bladder of any size, (let us suppose for the sake of illustration, the bladder to hold or
to be equal in capacity to 30,000 grains of water,) and having furnished it with a stop-cock
and a small jet pipe, fill it with the combustible gas the heating power of which is to be
tried. Take also a tinned iron vessel with a concave bottom of the same capacity, pour into
it as much water as will make the vessel and water together equal to the above stated bulk
of water in the bladder, viz. 30,000 grains. This being done, set fire to the gas at the orifice
of the pipe, and bring the point of the flame under the bottom of the tinned vessel, and
suffer it to burn there, by squeezing the bladder till the whole of the gas is consumed. The
increase of temperature of the water in the tinned vessel being carefully noticed before and
after the experiment, gives very accurately the heating power of the given bulk of the
inflammable gas.
It was thus proved that—
Olefiant gas raises an equal volume of water 14°
Carburetted hidrogen, or coal gas 10
Carbonic oxid 4
Hidrogen 5
Spermaceti oil 10 grains burnt in a lamp raised 30,000 grains of water 5
Tallow 5
Wax 5,75
Oil of turpentine 3
Spirit of wine 2
In all processes of the arts where a moderate heat is wanted the gas-light
flame will be found very advantageous—even on a large scale this flame
may be used with profit. It possesses advantages which cannot be obtained
from flaming fuel, where much nicety is required; because no fuel can be
managed like the flame of coal-gas. For it is well known, that when too
little air be given to flaming fuel it produces no flame, but sooty vapour;
and if too much air be admitted to make those vapours break out into flame,
the heat is often too violent. It is a fact, that flame, when produced in great
quantity, and made to burn violently, by mixing with a proper portion of
fresh air, driving it on the subject, and throwing it into whirls and eddies,
Page 63
thereby mixing the air with every part of the hot vapour, produces a very
intense heat.
The great power of a gas-flame does not appear when we try small
quantities of it, and allow it to burn quietly, because the air is not intimately
brought into contact with it, but acts only on the outside; and the quantity of
burning matter in the surface of a small flame is too minute to produce
much effect.
Larger image (252 kB)
But when the flame is produced in large quantity and is freely brought
forward into contact and agitated with air, its power to heat bodies is
immensely increased. It is therefore peculiarly proper for heating large
quantities of matter to a violent degree, especially if the contact of solid fuel
with such matter is inconvenient.
As the gas-flame may be made to assume any shape and intensity, and as
there is nothing to spill, it may be exhibited under such variety of forms and
designs, as cannot fail to give rise to the most tasteful ornamental
illumination.
intense heat.
The great power of a gas-flame does not appear when we try small
quantities of it, and allow it to burn quietly, because the air is not intimately
brought into contact with it, but acts only on the outside; and the quantity of
burning matter in the surface of a small flame is too minute to produce
much effect.
Larger image (252 kB)
But when the flame is produced in large quantity and is freely brought
forward into contact and agitated with air, its power to heat bodies is
immensely increased. It is therefore peculiarly proper for heating large
quantities of matter to a violent degree, especially if the contact of solid fuel
with such matter is inconvenient.
As the gas-flame may be made to assume any shape and intensity, and as
there is nothing to spill, it may be exhibited under such variety of forms and
designs, as cannot fail to give rise to the most tasteful ornamental
illumination.
Page 64
Plates III. IV. and V. exhibit such designs of different kinds of gas-lamps,
chandeliers, lustres, candelabras, &c. as are already in use in this
Metropolis.
Plate III. fig. 1, represents a Rod Lamp. The gas passes through the rod a,
to the Argand burner, which is surrounded by a cylindrical chimney, c,
swelling out at the lower extremity. The construction of the Argand burner
we have mentioned already, p. 78.
In all the gas-light burners, constructed on Argand’s plan, care should be
taken that the flame be in contact with the air on all sides, and that the
current of air be directed towards the upper extremity of the flame. This
may be effected by causing a current of air to rise up perpendicular from the
bottom of the chimney glass, and to pass out again through the contracted
part, or upper extremity of the chimney; but no other current of air should
ever be permitted to come near the gas-flame, or enter the glass chimney
which covers or defends the light; for if more air be permitted to mix with
the flame than is sufficient for the compleat combustion of the coal-gas, it
necessarily diminishes the heat, and consequently reduces the quantity of
light.
Fig. 2. A Rod Gas Lamp, with branches. The gas passes through the hollow
rod, a, and part of the hollow branch, b, to the burner of the lamp. The
cylindrical shaped glass, c, exhibited in this figure, is not so well adapted
for the compleat combustion of coal-gas, as the belly-shaped chimney, c,
represented in fig. 1, 3, 5, 6, because the ascending current of fresh air is
not turned out of its perpendicular course, and thrown immediately in a
concentrated state, into the upper part of the flame where the combustion of
the gas is less perfect. The exterior current of air which enters at the bottom
into the lamp, rises merely with a velocity proportioned to the length of the
cylinder, and to the rarefaction of the air in the same, but without being
propelled to the apex of the flame, as it should do, and is made to do, in the
bellied glass adapted to the lamp, fig. 1.
Fig. 3. A Bracket Lamp. a, the tube which conveys the gas to the burner; b,
the stop-cock of the tube.
Fig. 4. A Pendent Rod Lamp; in which the gas is supposed to come from a
pipe above, through the ceiling, into the pipe, a, to supply the burners. The
chandeliers, lustres, candelabras, &c. as are already in use in this
Metropolis.
Plate III. fig. 1, represents a Rod Lamp. The gas passes through the rod a,
to the Argand burner, which is surrounded by a cylindrical chimney, c,
swelling out at the lower extremity. The construction of the Argand burner
we have mentioned already, p. 78.
In all the gas-light burners, constructed on Argand’s plan, care should be
taken that the flame be in contact with the air on all sides, and that the
current of air be directed towards the upper extremity of the flame. This
may be effected by causing a current of air to rise up perpendicular from the
bottom of the chimney glass, and to pass out again through the contracted
part, or upper extremity of the chimney; but no other current of air should
ever be permitted to come near the gas-flame, or enter the glass chimney
which covers or defends the light; for if more air be permitted to mix with
the flame than is sufficient for the compleat combustion of the coal-gas, it
necessarily diminishes the heat, and consequently reduces the quantity of
light.
Fig. 2. A Rod Gas Lamp, with branches. The gas passes through the hollow
rod, a, and part of the hollow branch, b, to the burner of the lamp. The
cylindrical shaped glass, c, exhibited in this figure, is not so well adapted
for the compleat combustion of coal-gas, as the belly-shaped chimney, c,
represented in fig. 1, 3, 5, 6, because the ascending current of fresh air is
not turned out of its perpendicular course, and thrown immediately in a
concentrated state, into the upper part of the flame where the combustion of
the gas is less perfect. The exterior current of air which enters at the bottom
into the lamp, rises merely with a velocity proportioned to the length of the
cylinder, and to the rarefaction of the air in the same, but without being
propelled to the apex of the flame, as it should do, and is made to do, in the
bellied glass adapted to the lamp, fig. 1.
Fig. 3. A Bracket Lamp. a, the tube which conveys the gas to the burner; b,
the stop-cock of the tube.
Fig. 4. A Pendent Rod Lamp; in which the gas is supposed to come from a
pipe above, through the ceiling, into the pipe, a, to supply the burners. The
Page 65
tulip-shaped chimney, b, of this lamp, is likewise ill adapted for gas-light
burners.
Fig. 5. A pendent double-bracket Lamp. The gas passing through the
perpendicular tube, a, into the brackets, b b; c shows the Argand burner.
Fig. 6. A swing Bracket Lamp. a, the gas-pipe with its stop-cock; b, a brass
ball, communicating with the pipe, a; c, the conducting tube, ground air-
tight into the ball, b, and communicating with the burner of the lamp, so as
to allow it to have an horizontal motion.
Fig. 7. Shews the construction of the ball b, and pipe, c, of the lamp, fig. 6.
Fig. 8. A Swing Cockspur Lamp, constructed upon the same plan as fig. 6.
These two lamps are very convenient for desks in counting-houses, &c.
Fig. 9. A stop-cock with ball and socket, which, when adapted to a gas-light
pipe, allows it to have an universal motion, so that the light may be turned
in any direction.
Fig. 10. Section of the stop-cock, with ball and socket.
Fig. 11. Shows the ball and socket, fig. 9, in perspective.
burners.
Fig. 5. A pendent double-bracket Lamp. The gas passing through the
perpendicular tube, a, into the brackets, b b; c shows the Argand burner.
Fig. 6. A swing Bracket Lamp. a, the gas-pipe with its stop-cock; b, a brass
ball, communicating with the pipe, a; c, the conducting tube, ground air-
tight into the ball, b, and communicating with the burner of the lamp, so as
to allow it to have an horizontal motion.
Fig. 7. Shews the construction of the ball b, and pipe, c, of the lamp, fig. 6.
Fig. 8. A Swing Cockspur Lamp, constructed upon the same plan as fig. 6.
These two lamps are very convenient for desks in counting-houses, &c.
Fig. 9. A stop-cock with ball and socket, which, when adapted to a gas-light
pipe, allows it to have an universal motion, so that the light may be turned
in any direction.
Fig. 10. Section of the stop-cock, with ball and socket.
Fig. 11. Shows the ball and socket, fig. 9, in perspective.
Page 66
Larger image (205 kB)
Plate IV,[26] fig. 1. A Candelabrum; the gas pipe ascending from the floor
of the apartment, through the column a, and terminating in the burner of the
lamp.
[26] The gas-lamps exhibited in this plate, are employed in the library, counting-house,
warehouse, and offices of Mr. Ackerman, and, by whose permission, they are copied on
this occasion.
Fig. 2. A fancy pendent Cockspur Lamp. The gas being transmitted to the
burners, c c, by means of the pipe, a.
Fig. 3. A Pedestal Argand Lamp. a, the pipe and stop-cock, which transmits
to, and shuts off the gas from the burner of the lamp.
Fig. 4. A Pedestal Cockspur Lamp. a, the stop-cock and gas-pipe.
Fig. 5. A fancy bracket Cockspur Lamp, intended merely to show that the
coal-gas, as it passes to the burner, is perfectly devoid of colour, and
invisible. a is a glass vessel furnished at its orifice with a brass cap, c, and
perforated ball, out of which the gas-flame proceeds. b, the pipe which
conveys the gas into the glass vessel, a.
Fig. 6. A Bracket Argand Lamp. a and b, the gas pipe communicating with
the burner.
Fig. 7 and 8. A Horizontal Bracket Lamp. a, the gas pipe, supposed to be
concealed in the ceiling. b, the communicating pipe, which, together with c,
branches out at right angles at d d. e e, are the burners of the lamp.
Plate IV,[26] fig. 1. A Candelabrum; the gas pipe ascending from the floor
of the apartment, through the column a, and terminating in the burner of the
lamp.
[26] The gas-lamps exhibited in this plate, are employed in the library, counting-house,
warehouse, and offices of Mr. Ackerman, and, by whose permission, they are copied on
this occasion.
Fig. 2. A fancy pendent Cockspur Lamp. The gas being transmitted to the
burners, c c, by means of the pipe, a.
Fig. 3. A Pedestal Argand Lamp. a, the pipe and stop-cock, which transmits
to, and shuts off the gas from the burner of the lamp.
Fig. 4. A Pedestal Cockspur Lamp. a, the stop-cock and gas-pipe.
Fig. 5. A fancy bracket Cockspur Lamp, intended merely to show that the
coal-gas, as it passes to the burner, is perfectly devoid of colour, and
invisible. a is a glass vessel furnished at its orifice with a brass cap, c, and
perforated ball, out of which the gas-flame proceeds. b, the pipe which
conveys the gas into the glass vessel, a.
Fig. 6. A Bracket Argand Lamp. a and b, the gas pipe communicating with
the burner.
Fig. 7 and 8. A Horizontal Bracket Lamp. a, the gas pipe, supposed to be
concealed in the ceiling. b, the communicating pipe, which, together with c,
branches out at right angles at d d. e e, are the burners of the lamp.
Page 67
Larger image (286 kB)
Plate V. fig. 1. A Candelabrum, into which the gas-pipe ascends from the
floor of the apartment, the lateral branches communicating with the central
tube.
Fig. 2. An Arabesque Chandelier. The gas enters from the ceiling of the
room into the rope-shaped pipe, a, from which it proceeds through one of
the arched ribs, b b, into the horizontal hoop, or pipe, c.
Fig. 3. A Roman Chandelier. The gas enters through the inflexible hollow
chain, a, into the central tube, b, from whence the burners are supplied by
the lateral branches, c c.
Fig. 4. A Gothic Chandelier. The gas is transmitted to the burners through
the rope, a, which includes a tube, and the communication with the burners
is established through the lateral branches.
Fig. 5. A Pedestal Figure Lamp. The gas is here made to pass by means of a
pipe through the body of the figure into the lattice-work plateau,
constructed of hollow and perforated brass tubes.
Plate V. fig. 1. A Candelabrum, into which the gas-pipe ascends from the
floor of the apartment, the lateral branches communicating with the central
tube.
Fig. 2. An Arabesque Chandelier. The gas enters from the ceiling of the
room into the rope-shaped pipe, a, from which it proceeds through one of
the arched ribs, b b, into the horizontal hoop, or pipe, c.
Fig. 3. A Roman Chandelier. The gas enters through the inflexible hollow
chain, a, into the central tube, b, from whence the burners are supplied by
the lateral branches, c c.
Fig. 4. A Gothic Chandelier. The gas is transmitted to the burners through
the rope, a, which includes a tube, and the communication with the burners
is established through the lateral branches.
Fig. 5. A Pedestal Figure Lamp. The gas is here made to pass by means of a
pipe through the body of the figure into the lattice-work plateau,
constructed of hollow and perforated brass tubes.
Page 68
Fig. 6. A Pedestal Vase Lamp. The gas-tube enters through one of the claw-
feet of the altar-shaped pedestal, into the glass vase, a, at the bottom of
which it joins the tubes communicating with the metallic corn-ears, b, at the
upper extremities of which it forms jets de feu.
Fig. 7. A Girandole. The gas enters through the bracket, a, and is conveyed
to the burners by the descending tubes, b b.
Fig. 8. A Candelabrum, having a central pipe, through which the gas is
conducted to the burner at the top.
OTHER
PRODUCTS OBTAINABLE FROM COAL:
NAMELY,
COKE, TAR, ESSENTIAL OIL, &c.
Having thus far considered the nature of coal-gas as a substitute for the
lights now in use, it will be necessary to attend more particularly to some
other products which are obtained during the production of this species of
light: namely, coke, tar, ammoniacal liquor, &c.
Coke.—The substance called coke, which constitutes the skeleton of the
coal, or its carbonaceous base, is left behind in the retort, after all the
evaporable products have been expelled from the coal by heat.—See page
85.
It is sufficiently known, that coke is a more valuable fuel than the coal from
which it is obtained.
Hence, immense quantities are prepared in the large way, but the gazeous
and other substances are lost in the process employed for carbonizing the
coal.[27] In the manufacture of coal-gas, the coke comes from the retort,
enlarged in size, and greatly diminished in weight, when compared with the
original coal. In whatever state the coal may be when introduced into the
retort, the coke is uniformly taken out in large masses, so that the refuse
coal, or dust, and sweepings of the pit, which are now thrown away, may be
employed and converted into an excellent fuel. Coke is decidedly superior
feet of the altar-shaped pedestal, into the glass vase, a, at the bottom of
which it joins the tubes communicating with the metallic corn-ears, b, at the
upper extremities of which it forms jets de feu.
Fig. 7. A Girandole. The gas enters through the bracket, a, and is conveyed
to the burners by the descending tubes, b b.
Fig. 8. A Candelabrum, having a central pipe, through which the gas is
conducted to the burner at the top.
OTHER
PRODUCTS OBTAINABLE FROM COAL:
NAMELY,
COKE, TAR, ESSENTIAL OIL, &c.
Having thus far considered the nature of coal-gas as a substitute for the
lights now in use, it will be necessary to attend more particularly to some
other products which are obtained during the production of this species of
light: namely, coke, tar, ammoniacal liquor, &c.
Coke.—The substance called coke, which constitutes the skeleton of the
coal, or its carbonaceous base, is left behind in the retort, after all the
evaporable products have been expelled from the coal by heat.—See page
85.
It is sufficiently known, that coke is a more valuable fuel than the coal from
which it is obtained.
Hence, immense quantities are prepared in the large way, but the gazeous
and other substances are lost in the process employed for carbonizing the
coal.[27] In the manufacture of coal-gas, the coke comes from the retort,
enlarged in size, and greatly diminished in weight, when compared with the
original coal. In whatever state the coal may be when introduced into the
retort, the coke is uniformly taken out in large masses, so that the refuse
coal, or dust, and sweepings of the pit, which are now thrown away, may be
employed and converted into an excellent fuel. Coke is decidedly superior
Page 69
to coal for all domestic, and more especially for culinary purposes; the heat
which it throws out being more uniform, more intense, and more durable.
No flame, indeed, accompanies it, and it seldom needs the application of the
poker,—that specific for the ennui of Englishmen; but these deficiences are
more than balanced by the valuable property of emitting no sparks, of
giving more heat, and burning free from dust and smoke.
[27] The preparation of coke is as follows:—A quantity of large coal is placed on the
ground in a round heap, of from 12 to 15 feet in diameter, and about two feet in height; as
many as possible of the large pieces are placed on their ends, to form passages for the air;
above them are thrown the smaller pieces and coal dust, and in the midst of this circular
heap, is left, a vacancy of a foot wide where a few faggots are deposited to kindle it. Four
or five apertures of this kind are formed round the ring, particularly on the side exposed to
the wind; there is, however, seldom occasion to light it with wood, for other masses being
generally on fire, the workmen most frequently use a few shovels of coal already burning,
which acts more rapidly than wood, and soon kindles the surrounding pile; as the fire
spreads, the mass increases in bulk, puffs up, becomes spongy and light, cakes into one
body, and at length loses its volatile parts, and emits no more smoke. It then acquires an
uniform red colour, inclining a little to white, in which state it begins to break into gaps
and chinks, and assumes the appearance of the under part of a mushroom; at this moment
the heap must be quickly covered with ashes, of which there is always a sufficient
provision around the numerous fires, where the coke is prepared.
That coke must give out more heat during its combustion than coal, will at
once become obvious, when we consider that the quantity of matter which,
in the combustion of coal is changed from a solid to a state of elastic
fluidity, must necessarily carry off a portion of caloric, which then becomes
converted in a latent state without producing heat, whilst the glow of the
coke radiates caloric with an intensity unimpaired by any demand of this
kind.
It is thus that coke, though somewhat more difficult of ignition than
common coal, always gives out a more steady, a more lasting, and a more
intense heat.
The only inconveniences that attend the use of coke is, that, as it consumes,
it leaves much more ashes than common coal, charcoal, or wood; and these
much heavier too, which are, therefore, liable to collect in such quantity as
to obstruct the free passage of air through the fire; and further, that when the
heat is very intense, these ashes are disposed to melt or vitrify into a
tenacious drossy substance, which clogs the grate, the sides of the furnace
and the vessels. This last inconvenience is only troublesome, however,
which it throws out being more uniform, more intense, and more durable.
No flame, indeed, accompanies it, and it seldom needs the application of the
poker,—that specific for the ennui of Englishmen; but these deficiences are
more than balanced by the valuable property of emitting no sparks, of
giving more heat, and burning free from dust and smoke.
[27] The preparation of coke is as follows:—A quantity of large coal is placed on the
ground in a round heap, of from 12 to 15 feet in diameter, and about two feet in height; as
many as possible of the large pieces are placed on their ends, to form passages for the air;
above them are thrown the smaller pieces and coal dust, and in the midst of this circular
heap, is left, a vacancy of a foot wide where a few faggots are deposited to kindle it. Four
or five apertures of this kind are formed round the ring, particularly on the side exposed to
the wind; there is, however, seldom occasion to light it with wood, for other masses being
generally on fire, the workmen most frequently use a few shovels of coal already burning,
which acts more rapidly than wood, and soon kindles the surrounding pile; as the fire
spreads, the mass increases in bulk, puffs up, becomes spongy and light, cakes into one
body, and at length loses its volatile parts, and emits no more smoke. It then acquires an
uniform red colour, inclining a little to white, in which state it begins to break into gaps
and chinks, and assumes the appearance of the under part of a mushroom; at this moment
the heap must be quickly covered with ashes, of which there is always a sufficient
provision around the numerous fires, where the coke is prepared.
That coke must give out more heat during its combustion than coal, will at
once become obvious, when we consider that the quantity of matter which,
in the combustion of coal is changed from a solid to a state of elastic
fluidity, must necessarily carry off a portion of caloric, which then becomes
converted in a latent state without producing heat, whilst the glow of the
coke radiates caloric with an intensity unimpaired by any demand of this
kind.
It is thus that coke, though somewhat more difficult of ignition than
common coal, always gives out a more steady, a more lasting, and a more
intense heat.
The only inconveniences that attend the use of coke is, that, as it consumes,
it leaves much more ashes than common coal, charcoal, or wood; and these
much heavier too, which are, therefore, liable to collect in such quantity as
to obstruct the free passage of air through the fire; and further, that when the
heat is very intense, these ashes are disposed to melt or vitrify into a
tenacious drossy substance, which clogs the grate, the sides of the furnace
and the vessels. This last inconvenience is only troublesome, however,
Page 70
when the heat required is very great. In ordinary heats, such as are produced
by kitchen or parlour grates, the ashes do not melt, and though they are
more copious and heavy than those of charcoal or wood, they do not choke
up the fire, unless the bars of the grate be too close together.
The relative effects of heat produced by coke and coal are as follows:—
Six hundred pounds of pit-coal are capable of evaporating 10 cubic feet of
water in 20 hours, and 430lb. of coke are capable of evaporating 17 cubic
feet of water in 12 hours and a half.[28]
[28] In order to learn the relative effect of different kinds of fuel, with regard to their
capability of producing heat, chemistry teaches that equal quantities of fuel alike expended,
will raise the temperature of a given quantity of water through the same number of degrees;
whence, by knowing the original quantity and temperature of water, together with the
quantity of fuel expended to raise the water to the boiling point, the result sought may be
expressed by stating the quantity of water at 30 degrees, which would have been raised 180
degrees by one pound of the fuel employed; or in the form of a rule,
Multiply the quantity of water by the number expressing the degrees actually raised;
multiply the number of pounds of fuel expended by 180 degrees. Divide the first product
by the latter, and the quotient will express the water which would have been raised 180
degrees by one pound of the fuel. Or equal quantities of water may be compleatly
evaporated under equal surfaces and circumstances, with the different kinds of fuel, the
nature of which is to be examined; the quantities of fuel expended for that purpose give the
relative effect of the different kinds of fuel, with regard to their power of producing heat.
The Earl of Dundonald has shown that, in the application for burning lime,
a quantity of coke uniformly burns a given portion of lime-stone in one-
third part of the time that the quantity of coal from which the coke had been
made could do.
This effect is to be accounted for from having previously freed the coal, or
rather its coke, from the moisture and the tar, which it sends out during
combustion, and which condenses on the middle and upper strata of
stratified limestone and coal in the lime kiln, and impedes the whole mass
of materials from coming into a rapid and compleat ignition; because the
greater the quantity of materials, and the sooner the whole is ignited, the
better and more economically the lime is burned, both as to coals and time;
the saving of which last is a material object, especially at lime-kilns where
there is in the summer time a great demand for lime, the coke occasioning
the kilns to hold a third more lime at the same time.
by kitchen or parlour grates, the ashes do not melt, and though they are
more copious and heavy than those of charcoal or wood, they do not choke
up the fire, unless the bars of the grate be too close together.
The relative effects of heat produced by coke and coal are as follows:—
Six hundred pounds of pit-coal are capable of evaporating 10 cubic feet of
water in 20 hours, and 430lb. of coke are capable of evaporating 17 cubic
feet of water in 12 hours and a half.[28]
[28] In order to learn the relative effect of different kinds of fuel, with regard to their
capability of producing heat, chemistry teaches that equal quantities of fuel alike expended,
will raise the temperature of a given quantity of water through the same number of degrees;
whence, by knowing the original quantity and temperature of water, together with the
quantity of fuel expended to raise the water to the boiling point, the result sought may be
expressed by stating the quantity of water at 30 degrees, which would have been raised 180
degrees by one pound of the fuel employed; or in the form of a rule,
Multiply the quantity of water by the number expressing the degrees actually raised;
multiply the number of pounds of fuel expended by 180 degrees. Divide the first product
by the latter, and the quotient will express the water which would have been raised 180
degrees by one pound of the fuel. Or equal quantities of water may be compleatly
evaporated under equal surfaces and circumstances, with the different kinds of fuel, the
nature of which is to be examined; the quantities of fuel expended for that purpose give the
relative effect of the different kinds of fuel, with regard to their power of producing heat.
The Earl of Dundonald has shown that, in the application for burning lime,
a quantity of coke uniformly burns a given portion of lime-stone in one-
third part of the time that the quantity of coal from which the coke had been
made could do.
This effect is to be accounted for from having previously freed the coal, or
rather its coke, from the moisture and the tar, which it sends out during
combustion, and which condenses on the middle and upper strata of
stratified limestone and coal in the lime kiln, and impedes the whole mass
of materials from coming into a rapid and compleat ignition; because the
greater the quantity of materials, and the sooner the whole is ignited, the
better and more economically the lime is burned, both as to coals and time;
the saving of which last is a material object, especially at lime-kilns where
there is in the summer time a great demand for lime, the coke occasioning
the kilns to hold a third more lime at the same time.
Page 71
In the art of making bricks, in the smelting of metallic ores, and the drying
of malt, the advantages of coke over coal, are sufficiently known.
The following account given by Mr. Davis,[29] shows that the advantages
that may be derived in the processes of burning lime, plaster of paris, and
bricks, by means of coke, are greater than at first sight might be imagined.
[29] Philosophical Magazine, Vol. 33, p. 435.
“The coke obtained in the gas process is so valuable, that it appears
inexplicable that men should not avail themselves of this mode of procuring
light, to the almost total exclusion of all other methods now in use. As a
landholder, placed among an industrious but wholly illiterate society of
men, I have had the more opportunity of trying this species of fuel or coke,
which I could not otherwise procure in this sequestered spot, at a tolerably
cheap rate, for purposes to which it has not, as far as I know, been hitherto
employed. I must tell you that I am my own lime-burner, plaster of paris
baker, and brick-maker; and that in these processes of rural economy I have
derived the greatest benefits from this species of fuel, which I now prepare
at a cheap rate, although I waste almost the whole of the light of the coal
gas intentionally. The coal which I employed formerly for the burning of
limestone into lime, is a very inferior kind of small coal, called here Welsh
culm. The kiln for burning the limestone into lime is a cup-shaped
concavity, surrounded with solid brick-work, open at the top, and
terminating below by an iron grate. It has a stone door that may be opened
and closed for charging and emptying the furnace when required. This
furnace I formerly charged with alternate strata or layers of small coal and
limestone, the latter being broken previously into pieces not larger than a
man’s fist, until the kiln was completely filled. The stone is thus slowly
decomposed; the upper part of the charge descends, and when it has arrived
at the bottom of the furnace new strata are super-imposed, so as to keep the
furnace continually full during a period of 50 hours. The quantity of lime I
procured with small coal formerly amounted to 85 bushels. The strata of
coal necessary for the production of this quantity of lime require to be four
inches thick, and the time necessary for calcination was, as stated already,
50 hours.
“On applying coke instead of coal, the produce of lime may be increased to
nearly 30 per cent. from the same furnace, and the time required to effect
of malt, the advantages of coke over coal, are sufficiently known.
The following account given by Mr. Davis,[29] shows that the advantages
that may be derived in the processes of burning lime, plaster of paris, and
bricks, by means of coke, are greater than at first sight might be imagined.
[29] Philosophical Magazine, Vol. 33, p. 435.
“The coke obtained in the gas process is so valuable, that it appears
inexplicable that men should not avail themselves of this mode of procuring
light, to the almost total exclusion of all other methods now in use. As a
landholder, placed among an industrious but wholly illiterate society of
men, I have had the more opportunity of trying this species of fuel or coke,
which I could not otherwise procure in this sequestered spot, at a tolerably
cheap rate, for purposes to which it has not, as far as I know, been hitherto
employed. I must tell you that I am my own lime-burner, plaster of paris
baker, and brick-maker; and that in these processes of rural economy I have
derived the greatest benefits from this species of fuel, which I now prepare
at a cheap rate, although I waste almost the whole of the light of the coal
gas intentionally. The coal which I employed formerly for the burning of
limestone into lime, is a very inferior kind of small coal, called here Welsh
culm. The kiln for burning the limestone into lime is a cup-shaped
concavity, surrounded with solid brick-work, open at the top, and
terminating below by an iron grate. It has a stone door that may be opened
and closed for charging and emptying the furnace when required. This
furnace I formerly charged with alternate strata or layers of small coal and
limestone, the latter being broken previously into pieces not larger than a
man’s fist, until the kiln was completely filled. The stone is thus slowly
decomposed; the upper part of the charge descends, and when it has arrived
at the bottom of the furnace new strata are super-imposed, so as to keep the
furnace continually full during a period of 50 hours. The quantity of lime I
procured with small coal formerly amounted to 85 bushels. The strata of
coal necessary for the production of this quantity of lime require to be four
inches thick, and the time necessary for calcination was, as stated already,
50 hours.
“On applying coke instead of coal, the produce of lime may be increased to
nearly 30 per cent. from the same furnace, and the time required to effect
Page 72
the calcination of this quantity of lime-stone is reduced to 39 hours: it also
requires less attendance and less labour, and the whole saving, thus
accomplished, amounts to more than 50 per cent. on the lime-kiln.
“I have lately also employed coke for the burning of bricks. My bricks are
burnt in clamps, made of bricks themselves. The place for the fuel, or fire-
place, is perpendicular, about three feet high. The flues are formed by
gathering or arching the bricks over, so as to leave a space between each of
a brick’s breadth; and as the whole of the coal, if this fuel be employed,
must, on account of the construction of the pile, be put in at once, the
charge of the bricks is not, and never can be, burnt properly throughout; and
the interference of the legislature, with regard to the measurement of the
clamp, is a sufficient inducement for the manufacturer to allow no more
space for coal than he can possibly spare.
“If coke be applied instead of coal, the arches, or empty spaces in the clamp
or pile, as well as the strata of the fuel, may be considerably smaller: the
heat produced in this case is more uniform and more intense, and a saving
of 30 per cent. at least is gained.
“In the baking my own plaster-stone I also employ coke. The calcination of
the stone for manure I perform in a common reverberatory furnace, and the
men who conduct the process (who are otherwise averse to every thing
new) are much pleased with the steadiness of the fire, and little attendance
which the process requires, when coke is used instead of coal.
“These are the few facts I wish to state, with regard to the useful application
of this species of fuel, which, no doubt, hereafter will become an object of
economy of incalculable advantage to individuals, if its nature be better
understood than it is at present.”
The quantity of coke obtainable from a given quantity of coal varies
according to the nature of the coal employed. One chaldron of Newcastle
coal produced, upon an average, in the gas-light manufacture, from one
chaldron and a quarter to one chaldron and a half of well formed coke. If
the carbonization of the coal has been carried to its utmost point, the coke
produced, has a brilliant silvery lustre. Such coke is excellent for
metallurgical operations, because it stands the powerful blast of the bellows,
but for culinary and other purposes of domestic economy, the carbonization
requires less attendance and less labour, and the whole saving, thus
accomplished, amounts to more than 50 per cent. on the lime-kiln.
“I have lately also employed coke for the burning of bricks. My bricks are
burnt in clamps, made of bricks themselves. The place for the fuel, or fire-
place, is perpendicular, about three feet high. The flues are formed by
gathering or arching the bricks over, so as to leave a space between each of
a brick’s breadth; and as the whole of the coal, if this fuel be employed,
must, on account of the construction of the pile, be put in at once, the
charge of the bricks is not, and never can be, burnt properly throughout; and
the interference of the legislature, with regard to the measurement of the
clamp, is a sufficient inducement for the manufacturer to allow no more
space for coal than he can possibly spare.
“If coke be applied instead of coal, the arches, or empty spaces in the clamp
or pile, as well as the strata of the fuel, may be considerably smaller: the
heat produced in this case is more uniform and more intense, and a saving
of 30 per cent. at least is gained.
“In the baking my own plaster-stone I also employ coke. The calcination of
the stone for manure I perform in a common reverberatory furnace, and the
men who conduct the process (who are otherwise averse to every thing
new) are much pleased with the steadiness of the fire, and little attendance
which the process requires, when coke is used instead of coal.
“These are the few facts I wish to state, with regard to the useful application
of this species of fuel, which, no doubt, hereafter will become an object of
economy of incalculable advantage to individuals, if its nature be better
understood than it is at present.”
The quantity of coke obtainable from a given quantity of coal varies
according to the nature of the coal employed. One chaldron of Newcastle
coal produced, upon an average, in the gas-light manufacture, from one
chaldron and a quarter to one chaldron and a half of well formed coke. If
the carbonization of the coal has been carried to its utmost point, the coke
produced, has a brilliant silvery lustre. Such coke is excellent for
metallurgical operations, because it stands the powerful blast of the bellows,
but for culinary and other purposes of domestic economy, the carbonization
Page 73
should not be carried so far, because, the coke then produced, kindles more
readily and makes a more cheerful fire.
Coal-tar, Oil, and Pitch.—Another, valuable product obtainable from pit-
coal, is coal-tar.[30] This substance is deposited, in the purification of the
coal-gas, in a separate vessel destined to receive it.
[30] In the year 1665, Becher, a German chemist, brought to England his discovery for
extracting tar from coal, this distillation he performed in close vessels. It is not mentioned
in the records of the time, whether Becher obtained, or rather collected, any other articles
than the tar.
The coal-tar is so called from its resembling common tar in its appearance,
and most of its qualities.
Several works have been, at different times, erected both in England and on
the continent, to procure from coal a substitute for tar; but they turned out
unprofitable speculations. In 1781, the Earl of Dundonald invented a mode
of distilling coal in the large way, which enabled him not only to form coke,
but, at the same time, to save and collect the tar. Even this process however,
for which a patent was taken out, has gained very little ground. Its object
was still too limited; for though some of the ingredients of coal were
procured, they were procured at an expense that nearly balanced the profits;
and no attention whatever was paid to the coal gas, which constitutes the
most important part of coal.
Coal-tar may be used with advantage for painting and securing wood that is
exposed to the action of air or water. The wood being warmed, the tar is
applied cold, and penetrating into the pores, gives the timber an uncommon
degree of hardness and durability.
One chaldron of Newcastle coal produces in the gas-light manufacture from
150 to 180lb of tar, according to the circumstances under which it is
produced. See page 94.
The tar obtained from Newcastle coal-tar is specifically heavier than that
produced from cannel-coal; hence it sinks in water, whereas the latter
swims on the surface of that fluid.
To render the tar fit for use, it requires to be evaporated to give it a
sufficient consistence. If this process be performed in close vessels, a
readily and makes a more cheerful fire.
Coal-tar, Oil, and Pitch.—Another, valuable product obtainable from pit-
coal, is coal-tar.[30] This substance is deposited, in the purification of the
coal-gas, in a separate vessel destined to receive it.
[30] In the year 1665, Becher, a German chemist, brought to England his discovery for
extracting tar from coal, this distillation he performed in close vessels. It is not mentioned
in the records of the time, whether Becher obtained, or rather collected, any other articles
than the tar.
The coal-tar is so called from its resembling common tar in its appearance,
and most of its qualities.
Several works have been, at different times, erected both in England and on
the continent, to procure from coal a substitute for tar; but they turned out
unprofitable speculations. In 1781, the Earl of Dundonald invented a mode
of distilling coal in the large way, which enabled him not only to form coke,
but, at the same time, to save and collect the tar. Even this process however,
for which a patent was taken out, has gained very little ground. Its object
was still too limited; for though some of the ingredients of coal were
procured, they were procured at an expense that nearly balanced the profits;
and no attention whatever was paid to the coal gas, which constitutes the
most important part of coal.
Coal-tar may be used with advantage for painting and securing wood that is
exposed to the action of air or water. The wood being warmed, the tar is
applied cold, and penetrating into the pores, gives the timber an uncommon
degree of hardness and durability.
One chaldron of Newcastle coal produces in the gas-light manufacture from
150 to 180lb of tar, according to the circumstances under which it is
produced. See page 94.
The tar obtained from Newcastle coal-tar is specifically heavier than that
produced from cannel-coal; hence it sinks in water, whereas the latter
swims on the surface of that fluid.
To render the tar fit for use, it requires to be evaporated to give it a
sufficient consistence. If this process be performed in close vessels, a
Page 74
portion of an essential oil is obtained, which is known to colourmen by the
name of oil of tar. To obtain this oil, a common still is filled with the coal-
tar, and, being properly luted, the fire is kindled and kept up very moderate,
for the tar is very apt to boil up in the early part of the process. The first
product that distils over is principally a brown ammoniacal fluid, mixed
however with a good deal of oil. As the process advances, and the heat is
increased, the quantity of ammoniacal liquor lessens, and that of oil
increases, and towards the end of the distillation the product is chiefly oil.
The oil and ammoniacal water which distil over do not mix, so that they
may be easily separated by decantation. The oil is a yellowish inferior kind
of oil of turpentine, which is very useful in painting ships, for making
varnishes, and other coarse out-door work.
Two hundred pounds of tar produce, upon an average, fifty-three pounds of
essential oil.
If the coal-tar is wanted to be converted into pitch, without obtaining the oil
which it is capable of furnishing, the evaporation of it may be performed in
a common boiler; but as it is extremely liable to boil over, the greatest
precaution is necessary in conducting the evaporation. A boiler constructed
on the following plan is very convenient for the conversion of coal-tar into
pitch. The contrivance consists in adding a spout, or rim, to the common
boiler, into which the tar spreads itself as it rises, and by this means
becomes cooled, and the boiling over is checked.
Kettle for boiling Tar.
name of oil of tar. To obtain this oil, a common still is filled with the coal-
tar, and, being properly luted, the fire is kindled and kept up very moderate,
for the tar is very apt to boil up in the early part of the process. The first
product that distils over is principally a brown ammoniacal fluid, mixed
however with a good deal of oil. As the process advances, and the heat is
increased, the quantity of ammoniacal liquor lessens, and that of oil
increases, and towards the end of the distillation the product is chiefly oil.
The oil and ammoniacal water which distil over do not mix, so that they
may be easily separated by decantation. The oil is a yellowish inferior kind
of oil of turpentine, which is very useful in painting ships, for making
varnishes, and other coarse out-door work.
Two hundred pounds of tar produce, upon an average, fifty-three pounds of
essential oil.
If the coal-tar is wanted to be converted into pitch, without obtaining the oil
which it is capable of furnishing, the evaporation of it may be performed in
a common boiler; but as it is extremely liable to boil over, the greatest
precaution is necessary in conducting the evaporation. A boiler constructed
on the following plan is very convenient for the conversion of coal-tar into
pitch. The contrivance consists in adding a spout, or rim, to the common
boiler, into which the tar spreads itself as it rises, and by this means
becomes cooled, and the boiling over is checked.
Kettle for boiling Tar.
Page 75
1000lb. of coal-tar produce, upon an average, from 460 to 480lb. of pitch. A
subsequent fusion, with a gentle heat, converts the coal-pitch into a
substance possessing all the characters of asphaltum.
Ammoniacal Fluid.—The properties of the ammoniacal liquor, which
accompanies the tar, and which is deposited in the tar-cistern, has not yet
been fully investigated. It is employed already in the manufacture of
muriate of ammonia (sal ammoniac). One chaldron of coal affords from 220
to 240lb. of this ammoniacal fluid, which is composed chiefly of sulphate,
and carbonate of ammonia.—Such are the products obtainable from coal.
However certain the practicability of extending the new lights to the
dwelling houses of every town and village is, it cannot be expected that
such an event should take place speedily and generally. To eradicate
prejudice, and to alter established habits, is a work which nothing but time
can effect; because prejudice is the effect of habit, and can seldom be
eradicated from the minds of such individuals as consider the ready
occurrence of a proposition as a test of its truth. To establish a new
philosophical theory has, in every instance, required time sufficient to
educate an entire generation of men. The rejection of the Aristotelian
philosophy—the adoption of experimental research—the substitution of the
doctrine of gravitation instead of that of vortices, and the rejection of
phlogiston by modern chemists, are sufficiently illustrative of this assertion.
New arts, and new practices, are still more difficult to be introduced. The
new art of bleaching need merely be mentioned to prove this assertion. The
new grammar—the new rudiments of science—the new stile—or the new
instrument, however superior to the old in simplicity, facility, and truth,
must be less valuable to the ordinary teacher or artisan, whose memory is
familiarized with the precepts of the latter, and whose only ambition is to
earn his subsistence with the least possible exertion.
The slowness with which improvements of every kind, make their way into
common use, and especially such discoveries as are most calculated to be of
an extended or general utility is very remarkable, and forms a striking
contrast to the extreme avidity with which those unmeaning changes are
adopted, which folly and caprice are continually sending forth into the
world under the auspices of fashion.
subsequent fusion, with a gentle heat, converts the coal-pitch into a
substance possessing all the characters of asphaltum.
Ammoniacal Fluid.—The properties of the ammoniacal liquor, which
accompanies the tar, and which is deposited in the tar-cistern, has not yet
been fully investigated. It is employed already in the manufacture of
muriate of ammonia (sal ammoniac). One chaldron of coal affords from 220
to 240lb. of this ammoniacal fluid, which is composed chiefly of sulphate,
and carbonate of ammonia.—Such are the products obtainable from coal.
However certain the practicability of extending the new lights to the
dwelling houses of every town and village is, it cannot be expected that
such an event should take place speedily and generally. To eradicate
prejudice, and to alter established habits, is a work which nothing but time
can effect; because prejudice is the effect of habit, and can seldom be
eradicated from the minds of such individuals as consider the ready
occurrence of a proposition as a test of its truth. To establish a new
philosophical theory has, in every instance, required time sufficient to
educate an entire generation of men. The rejection of the Aristotelian
philosophy—the adoption of experimental research—the substitution of the
doctrine of gravitation instead of that of vortices, and the rejection of
phlogiston by modern chemists, are sufficiently illustrative of this assertion.
New arts, and new practices, are still more difficult to be introduced. The
new art of bleaching need merely be mentioned to prove this assertion. The
new grammar—the new rudiments of science—the new stile—or the new
instrument, however superior to the old in simplicity, facility, and truth,
must be less valuable to the ordinary teacher or artisan, whose memory is
familiarized with the precepts of the latter, and whose only ambition is to
earn his subsistence with the least possible exertion.
The slowness with which improvements of every kind, make their way into
common use, and especially such discoveries as are most calculated to be of
an extended or general utility is very remarkable, and forms a striking
contrast to the extreme avidity with which those unmeaning changes are
adopted, which folly and caprice are continually sending forth into the
world under the auspices of fashion.
Page 76
On the first view of the subject it appears very extraordinary, that any
person should neglect, or refuse to avail himself of a proposed invention, or
improvement, which is evidently calculated to economise his labour, and to
encrease his comforts; but when we reflect on the power of habit, and
consider how difficult it is for a person even to perceive the disadvantages
or imperfections of former modes to which he has been accustomed from
his early youth, our surprize will be diminished, or vanish altogether.
Many other circumstances, besides prejudice, are unfavourable to the
introduction of new and useful discoveries. Among these jealousy, malice,
envy, and revenge, have too often their share in obstructing the progress of
real improvement, and in preventing the adoption of plans evidently
calculated to promote the public good.
A plan like the present, which proposes not only to trench upon domestic
habits, but to give an entire new direction to a portion of the skill and
capital of the country, must necessarily encounter the most strenuous
opposition. It is thus that some individuals have mustered all their strength
against the introduction of this new art. An endeavour has been made to
move the public opinion by dismal forebodings of the Greenland trade, and
the subsequent loss of a nursery of British seamen. This objection is nothing
more than the common clamour that is always set up against every new
means of abridging labour, to which had the public listened, an interdict
would have been laid upon the spinning and threshing machines, the steam
engine, and a thousand other improvements in machinery.
Indeed such clamour scarcely ever fails to be made when the extension of
machinery and the abridgement of labour or the application of inanimate
powers are considered. On such occasions, it is stated by certain humane
but mistaken objectors, that the scheme of mechanical and chemical
improvement is pointed against the human species—that it tends to drive
them out of the system of beneficial employment—that the introduction of
machinery is injurious to the labouring class of society, by abridging their
work. Two creatures offer themselves for employment and support—a man
and a horse. I must invariably prefer the latter, and leave the former to
starve. Two other beings—a horse and a steam-engine, are candidates for
my favour. My preference to the latter tends to exterminate the species of
the former. In both cases it is stated, that the number of intelligent creatures
person should neglect, or refuse to avail himself of a proposed invention, or
improvement, which is evidently calculated to economise his labour, and to
encrease his comforts; but when we reflect on the power of habit, and
consider how difficult it is for a person even to perceive the disadvantages
or imperfections of former modes to which he has been accustomed from
his early youth, our surprize will be diminished, or vanish altogether.
Many other circumstances, besides prejudice, are unfavourable to the
introduction of new and useful discoveries. Among these jealousy, malice,
envy, and revenge, have too often their share in obstructing the progress of
real improvement, and in preventing the adoption of plans evidently
calculated to promote the public good.
A plan like the present, which proposes not only to trench upon domestic
habits, but to give an entire new direction to a portion of the skill and
capital of the country, must necessarily encounter the most strenuous
opposition. It is thus that some individuals have mustered all their strength
against the introduction of this new art. An endeavour has been made to
move the public opinion by dismal forebodings of the Greenland trade, and
the subsequent loss of a nursery of British seamen. This objection is nothing
more than the common clamour that is always set up against every new
means of abridging labour, to which had the public listened, an interdict
would have been laid upon the spinning and threshing machines, the steam
engine, and a thousand other improvements in machinery.
Indeed such clamour scarcely ever fails to be made when the extension of
machinery and the abridgement of labour or the application of inanimate
powers are considered. On such occasions, it is stated by certain humane
but mistaken objectors, that the scheme of mechanical and chemical
improvement is pointed against the human species—that it tends to drive
them out of the system of beneficial employment—that the introduction of
machinery is injurious to the labouring class of society, by abridging their
work. Two creatures offer themselves for employment and support—a man
and a horse. I must invariably prefer the latter, and leave the former to
starve. Two other beings—a horse and a steam-engine, are candidates for
my favour. My preference to the latter tends to exterminate the species of
the former. In both cases it is stated, that the number of intelligent creatures
Page 77
capable of the enjoyment of happiness must be diminished for want of
support; and that, on the whole, the sum of the proposed improvement is not
only a less proportion of good to society, but a positive accession of misery
to the unemployed poor.
On this wide and extended argument, which can in fact be maintained
against all improvements whatever in no other way than by insisting that
the savage state of man, with all its wants, its ignorance, its ferocity, and its
privations, is preferable to the social intercourse of effort and division of
labour we are habituated to prefer, it may be sufficient to observe that it
includes matter not only for reasoning and induction, but also for
experiment. By reference to the matter of fact, though it must be allowed
that new improvements, which change the habits of the poor, must at first
expose them to a temporary inconvenience and distress, against which, in
fairness, it is the duty of society to defend them; yet the invariable result of
such improvements is always to better the condition of mankind. A
temporary inconvenience to individuals must often be incurred for the sake
of general national benefit.
It is to manufactories carried on by machinery and to the abridgment of
labour, that this country is indebted for her riches, her independence and
pre-eminent station among the nations of the world.
But let us return to the subject.—The progress of the new mode of lighting
with coal-gas can never wholly supersede the use of candles and moveable
lights. The objection with regard to the Greenland trade is equally futile.
This traffic, might with more propriety be called a drain, than a nursery, of
the naval force. The nature of the Greenland service requires that the crew
should consist chiefly of able-bodied sailors; and being protected men, not
subject to the impress law, they are thus rendered useless for national
defence. The nursery of British seamen is the coasting trade; and if the gas-
light illumination be put in practice to a large extent, it will increase that
trade as much as it will diminish the Greenland fishery.
Even on the extreme supposition that it would annihilate the Greenland
fisheries altogether, we should have no reason to regret the event. The
soundest principles of political economy must condemn the practice of
fitting out vessels to navigate the polar seas for oil, if we can extract a
support; and that, on the whole, the sum of the proposed improvement is not
only a less proportion of good to society, but a positive accession of misery
to the unemployed poor.
On this wide and extended argument, which can in fact be maintained
against all improvements whatever in no other way than by insisting that
the savage state of man, with all its wants, its ignorance, its ferocity, and its
privations, is preferable to the social intercourse of effort and division of
labour we are habituated to prefer, it may be sufficient to observe that it
includes matter not only for reasoning and induction, but also for
experiment. By reference to the matter of fact, though it must be allowed
that new improvements, which change the habits of the poor, must at first
expose them to a temporary inconvenience and distress, against which, in
fairness, it is the duty of society to defend them; yet the invariable result of
such improvements is always to better the condition of mankind. A
temporary inconvenience to individuals must often be incurred for the sake
of general national benefit.
It is to manufactories carried on by machinery and to the abridgment of
labour, that this country is indebted for her riches, her independence and
pre-eminent station among the nations of the world.
But let us return to the subject.—The progress of the new mode of lighting
with coal-gas can never wholly supersede the use of candles and moveable
lights. The objection with regard to the Greenland trade is equally futile.
This traffic, might with more propriety be called a drain, than a nursery, of
the naval force. The nature of the Greenland service requires that the crew
should consist chiefly of able-bodied sailors; and being protected men, not
subject to the impress law, they are thus rendered useless for national
defence. The nursery of British seamen is the coasting trade; and if the gas-
light illumination be put in practice to a large extent, it will increase that
trade as much as it will diminish the Greenland fishery.
Even on the extreme supposition that it would annihilate the Greenland
fisheries altogether, we should have no reason to regret the event. The
soundest principles of political economy must condemn the practice of
fitting out vessels to navigate the polar seas for oil, if we can extract a
Page 78
superior material for procuring light at a cheaper rate from the produce of
our own soil.
Indeed the fisheries will find ample encouragement, and the consequence of
lighting our streets with gas can prove injurious only to our continental
friends, one of whose staple commodities, tallow, we shall then have less
occasion to purchase.
There will be less waste indeed, but a greater consumption of coal. The
lower classes of the community are at present very scantily supplied with
firing; and nothing but a reduction of price is necessary to increase to a very
large amount the whole average quantity of fuel consumed in the country.
The lightness of the coke produced in the gas-light manufacture
diminishing the expence of land carriage, will facilitate its general diffusion
—the comforts of the poor will be materially augmented, and a number of
useful operations in agriculture and the arts be carried on, which are now
checked and impeded by the price of fuel.
If any additional want were wanted for the coke it will readily be found in
the continental market; coke being much better suited than coal to the habits
of most European nations.
The gas-light illumination cannot tend to diminish the coal-trade; on the
contrary it will prove beneficial to it; it will contribute to lower the price of
the superior kinds of coal, and keep a level which cannot be shaken under
any circumstances; it will contribute to prevent combinations which do
certainly operate to the prejudice of the public, and do sometimes put this
great town at the mercy of particular proprietors in the north, who deal out
coal in the way they please. The competition thus produced, it is impossible
not to consider as an advantage, which would prevent in future such
combinations, and put those in London out of the reach of them.
It is worthy observation, that the annual importation of coal into this
Metropolis, is above one million and eighty-eight thousand chaldrons.[31]
[31] To give an idea how long there is a probability of Great Britain being applied with
coal from the rivers Tyne and Wear only, it must be observed,
1st. That the Seams of coal which are now worked at Newcastle and Sunderland, are equal
to a seam or bed of 15 miles by 20 miles.
our own soil.
Indeed the fisheries will find ample encouragement, and the consequence of
lighting our streets with gas can prove injurious only to our continental
friends, one of whose staple commodities, tallow, we shall then have less
occasion to purchase.
There will be less waste indeed, but a greater consumption of coal. The
lower classes of the community are at present very scantily supplied with
firing; and nothing but a reduction of price is necessary to increase to a very
large amount the whole average quantity of fuel consumed in the country.
The lightness of the coke produced in the gas-light manufacture
diminishing the expence of land carriage, will facilitate its general diffusion
—the comforts of the poor will be materially augmented, and a number of
useful operations in agriculture and the arts be carried on, which are now
checked and impeded by the price of fuel.
If any additional want were wanted for the coke it will readily be found in
the continental market; coke being much better suited than coal to the habits
of most European nations.
The gas-light illumination cannot tend to diminish the coal-trade; on the
contrary it will prove beneficial to it; it will contribute to lower the price of
the superior kinds of coal, and keep a level which cannot be shaken under
any circumstances; it will contribute to prevent combinations which do
certainly operate to the prejudice of the public, and do sometimes put this
great town at the mercy of particular proprietors in the north, who deal out
coal in the way they please. The competition thus produced, it is impossible
not to consider as an advantage, which would prevent in future such
combinations, and put those in London out of the reach of them.
It is worthy observation, that the annual importation of coal into this
Metropolis, is above one million and eighty-eight thousand chaldrons.[31]
[31] To give an idea how long there is a probability of Great Britain being applied with
coal from the rivers Tyne and Wear only, it must be observed,
1st. That the Seams of coal which are now worked at Newcastle and Sunderland, are equal
to a seam or bed of 15 miles by 20 miles.
Page 79
2dly. That this seam, on an average, is at least four feet and a half thick.
3dly, That 1-6th part of the above extent is sufficient for pillars to support the roofs of the
mines, &c.
And, 4thly, It appears, by experiments, that a cubic yard of coal weighs 1 ton, or 20 cwt.
London
Chaldrons
The total consumption of coal from the rivers Tyne and Wear known from
the register to be 2,300,000
The number of tons in the above quantity taking the London chaldron at
27 cwt. is 3,100,000
Now a ton weight of coal is estimated to occupy in the earth the space of one cubic yard.
The number of cubic yards in the square mile is 3,097,600
The beds or seams of coal are, on an average, 4 feet and a half in
thickness, which increases the above number of cubic yards in the square
mile by half the number of square yards to 1,548,800
And hence the square mile of the beds or seams of coal we are describing
contains, of cubic yards and tons of coal 4,645,000
A deduction of 1-6th for pillars to support the mine, &c. 800,000
The number of tons per square mile 5,445,000
We have already mentioned the length and breadth of the seams of coal to be equal to 20
miles by 15, making an area of 300 square miles, and consequently a source of
consumption for 375 years.
It may be objected to the universality of our conclusion, that the price of
coals, differing very much in different places, will occasion a variation in
the expence of the new mode of illumination. But there are two reasons
why this should have less place, because we find, in Mr. Murdoch’s
statement, page 69, that of 600l. the estimated yearly expence of lighting
the cotton mill, 550l. consist of interest of capital, and tear and wear of
apparatus, leaving the cost of coal only 50l. a sum so trifling, when we
reflect that it replaces 2000l. worth of candles, that the price of coal, even
where it is highest, can but slightly affect the general profits.[32]
[32] See, also, Mr. Ackermann’s statement, page 71.
2dly, The coal, by yielding the gas and other products,—namely, tar, pitch,
ammoniacal liquor, &c. of which we have treated already, is converted into
a substance, increased in bulk, and in the power of producing heat, namely,
coke; and as a manufactory generally requires heating as well as lighting,
there will be a gain both ways. The manufacturer, by distilling his coal,
instead of burning it as it comes from the pit, will save his candles and
3dly, That 1-6th part of the above extent is sufficient for pillars to support the roofs of the
mines, &c.
And, 4thly, It appears, by experiments, that a cubic yard of coal weighs 1 ton, or 20 cwt.
London
Chaldrons
The total consumption of coal from the rivers Tyne and Wear known from
the register to be 2,300,000
The number of tons in the above quantity taking the London chaldron at
27 cwt. is 3,100,000
Now a ton weight of coal is estimated to occupy in the earth the space of one cubic yard.
The number of cubic yards in the square mile is 3,097,600
The beds or seams of coal are, on an average, 4 feet and a half in
thickness, which increases the above number of cubic yards in the square
mile by half the number of square yards to 1,548,800
And hence the square mile of the beds or seams of coal we are describing
contains, of cubic yards and tons of coal 4,645,000
A deduction of 1-6th for pillars to support the mine, &c. 800,000
The number of tons per square mile 5,445,000
We have already mentioned the length and breadth of the seams of coal to be equal to 20
miles by 15, making an area of 300 square miles, and consequently a source of
consumption for 375 years.
It may be objected to the universality of our conclusion, that the price of
coals, differing very much in different places, will occasion a variation in
the expence of the new mode of illumination. But there are two reasons
why this should have less place, because we find, in Mr. Murdoch’s
statement, page 69, that of 600l. the estimated yearly expence of lighting
the cotton mill, 550l. consist of interest of capital, and tear and wear of
apparatus, leaving the cost of coal only 50l. a sum so trifling, when we
reflect that it replaces 2000l. worth of candles, that the price of coal, even
where it is highest, can but slightly affect the general profits.[32]
[32] See, also, Mr. Ackermann’s statement, page 71.
2dly, The coal, by yielding the gas and other products,—namely, tar, pitch,
ammoniacal liquor, &c. of which we have treated already, is converted into
a substance, increased in bulk, and in the power of producing heat, namely,
coke; and as a manufactory generally requires heating as well as lighting,
there will be a gain both ways. The manufacturer, by distilling his coal,
instead of burning it as it comes from the pit, will save his candles and
Page 80
improve his fuel. One effort at the outset, in erecting a proper apparatus,
will reduce his annual disbursement, for these two articles of prime
necessity, much in the same manner, (though in a far greater degree) as the
farmer gains by building a thrashing machine and laying aside the use of the
flail.
The principal expence in the pursuit of this branch of civil and domestic
economy is therefore the dead capital employed in erecting the machinery
destined for preparing and conveying the gas; the floating or live capital is
comparatively small. At the same time, were we to offer an advice to the
public on this subject, it would be, that no private individual resident in
London should attempt to light his premises for the sake of economy with
coal-gas by means of his own apparatus, whose annual expence for light
does not exceed 60l. because the expence of erecting and attending a small
apparatus is almost as great as one constructed on a larger scale would be.
For if the quantity of gas wanted is not sufficient to keep the retorts
continually in a red-hot or working state, the cost of the gas will be
considerably enhanced; because either the empty retorts must be continued
red-hot, or the fire must be suffered to go out; and the retorts, when cold,
cannot be brought to a working state, that is to say, be made red hot again,
but at a considerable expence of fuel, which must be wasted to no purpose.
Whereas, if the retorts are constantly kept red hot and in action, one half of
the coal necessary to produce a given quantity of gas will then be saved.
But when a street, or a small neighbourhood is wanted to be lighted, and the
retorts can always be kept in a working state, that is to say, red hot, the
operation may be commenced with safety; because the sum required for
erecting the apparatus, and the labour attending it, together with the interest
of money sunk, will then soon be liquidated by the light which it will
afford.
Individuals, therefore, may engage in the distillation of coal, and trade with
advantage in the articles produced by that process, and the lighting of cities
may be accomplished without the aid of incorporated bodies; and parishes
may be lighted by almost as many individuals as there are streets in a
parish.
From experiments, made by Mr. Clegg, on the effects produced by a
number of gas-lights, of a certain intensity, there is reason to believe that
will reduce his annual disbursement, for these two articles of prime
necessity, much in the same manner, (though in a far greater degree) as the
farmer gains by building a thrashing machine and laying aside the use of the
flail.
The principal expence in the pursuit of this branch of civil and domestic
economy is therefore the dead capital employed in erecting the machinery
destined for preparing and conveying the gas; the floating or live capital is
comparatively small. At the same time, were we to offer an advice to the
public on this subject, it would be, that no private individual resident in
London should attempt to light his premises for the sake of economy with
coal-gas by means of his own apparatus, whose annual expence for light
does not exceed 60l. because the expence of erecting and attending a small
apparatus is almost as great as one constructed on a larger scale would be.
For if the quantity of gas wanted is not sufficient to keep the retorts
continually in a red-hot or working state, the cost of the gas will be
considerably enhanced; because either the empty retorts must be continued
red-hot, or the fire must be suffered to go out; and the retorts, when cold,
cannot be brought to a working state, that is to say, be made red hot again,
but at a considerable expence of fuel, which must be wasted to no purpose.
Whereas, if the retorts are constantly kept red hot and in action, one half of
the coal necessary to produce a given quantity of gas will then be saved.
But when a street, or a small neighbourhood is wanted to be lighted, and the
retorts can always be kept in a working state, that is to say, red hot, the
operation may be commenced with safety; because the sum required for
erecting the apparatus, and the labour attending it, together with the interest
of money sunk, will then soon be liquidated by the light which it will
afford.
Individuals, therefore, may engage in the distillation of coal, and trade with
advantage in the articles produced by that process, and the lighting of cities
may be accomplished without the aid of incorporated bodies; and parishes
may be lighted by almost as many individuals as there are streets in a
parish.
From experiments, made by Mr. Clegg, on the effects produced by a
number of gas-lights, of a certain intensity, there is reason to believe that
Page 81
the streets of small towns might be illuminated at a cheaper rate, by means
of a tower, or pagoda, furnished with gas-lamps, than can be done in the
ordinary way by street lamps: the gas being conducted to the top of the
building from the apparatus below, and the light directed down again, upon
the objects to be illuminated, by means of reflectors placed at a certain
angle. By this contrivance, all the main pipes which convey the gas through
the streets, as well as those collateral ones that branch out from them to the
street lamps, would be saved, and thus compensate for the expense of the
tower.
The most beneficial application of gas-lights unquestionably is in all those
situations where a great quantity of light is wanted in a small place: and
where light is required to be most diffused, the advantages of this mode of
illumination are the least.—Hence, as already stated, the lighting of the
parish, or street-lamps only, without lighting shops or houses, can never be
accomplished with economy.
We have noticed before the reason why the price of coals can have little
effect upon the gas-light; because the very refuse, or small coals, called
slack, which pass through the screen at the pit’s mouth, and which cannot
be brought into the market—nay, even the sweepings of the pit, which are
thrown away, may be employed for the production of coal-gas. It makes no
difference in what form the coal is used, and this circumstance may
contribute to enable the coal-merchant to furnish coals in larger masses, and
as they come from the mine, instead of increasing the bulk by breaking
them into a smaller size,[33] which is a practice commonly adhered to. This
unquestionably reduces the value of coals; because the quantity of radiant
heat generated in the combustion of a given quantity of any kind of fuel
depends much upon the management of the fire, or upon the manner in
which the fuel is consumed. When the fire burns bright, much radiant heat
will be sent off from it; but when it is smothered up, very little will be
generated: most of the heat produced will then be expended in giving
elasticity to a thick dense vapour, or smoke, which is seen rising from the
fire; and the combustion being very incomplete, the carburetted hidrogen
gas of the coal being driven up the chimney without being inflamed, the
fuel is wasted to little purpose.
[33] It is not generally apprehended, how very wasteful the use of small coals is in the
ordinary open fire-grates. Necessity makes us use the poker very much, particularly, when
of a tower, or pagoda, furnished with gas-lamps, than can be done in the
ordinary way by street lamps: the gas being conducted to the top of the
building from the apparatus below, and the light directed down again, upon
the objects to be illuminated, by means of reflectors placed at a certain
angle. By this contrivance, all the main pipes which convey the gas through
the streets, as well as those collateral ones that branch out from them to the
street lamps, would be saved, and thus compensate for the expense of the
tower.
The most beneficial application of gas-lights unquestionably is in all those
situations where a great quantity of light is wanted in a small place: and
where light is required to be most diffused, the advantages of this mode of
illumination are the least.—Hence, as already stated, the lighting of the
parish, or street-lamps only, without lighting shops or houses, can never be
accomplished with economy.
We have noticed before the reason why the price of coals can have little
effect upon the gas-light; because the very refuse, or small coals, called
slack, which pass through the screen at the pit’s mouth, and which cannot
be brought into the market—nay, even the sweepings of the pit, which are
thrown away, may be employed for the production of coal-gas. It makes no
difference in what form the coal is used, and this circumstance may
contribute to enable the coal-merchant to furnish coals in larger masses, and
as they come from the mine, instead of increasing the bulk by breaking
them into a smaller size,[33] which is a practice commonly adhered to. This
unquestionably reduces the value of coals; because the quantity of radiant
heat generated in the combustion of a given quantity of any kind of fuel
depends much upon the management of the fire, or upon the manner in
which the fuel is consumed. When the fire burns bright, much radiant heat
will be sent off from it; but when it is smothered up, very little will be
generated: most of the heat produced will then be expended in giving
elasticity to a thick dense vapour, or smoke, which is seen rising from the
fire; and the combustion being very incomplete, the carburetted hidrogen
gas of the coal being driven up the chimney without being inflamed, the
fuel is wasted to little purpose.
[33] It is not generally apprehended, how very wasteful the use of small coals is in the
ordinary open fire-grates. Necessity makes us use the poker very much, particularly, when
Page 82
the coals are small; and habit prevails even when they are large. By the constant stirring of
the fire almost the whole of the small coal passes through the bars; and consequently a
great deal goes to the dust-hole without being burnt at all. To prove this, we need only take
a shovel full of ashes and put them into a pail, and then pouring water over them, which
being gently run off, will carry away nearly all the light and burnt parts: and leave an
astonishing quantity of bright unburnt coal, which has escaped from the fire-place, in
consequence of being small.
When the grate of the fire-place is large, and the small coals are thrown behind; or when
we can have patience enough to bear the cold for an hour or two, or contrive to have the
fire lighted a long time before we want it, the small coal may be of some use, but the fire
made with it is never strong, nor so bright; and does not burn so long as a fire made with
large or round coals: it often requires the help of the poker, and produces a great quantity
of breeze.
The loss in the use of small coals is more considerable to the poor, who cannot keep large
fires. When they want their breakfast or dinner, the time they can spare is limited; and to
have their water sooner boiling, or their meals quicker ready; they must make use of the
poker, and lose a great deal of coal. This fact is so evident, that any body who wishes to
make the experiment before recommended, will find that much more bright coal goes to
the dust-hole of the poor man, than to the dust-hole of a rich family, where, the fire-place
being large, the small coal has more chance of burning.
The loss is still greater to the poor, in consequence of the inferior sorts of coal which are
sold to them. If it is the light sort, it burns too quick, and they consume double the quantity;
if the strong sort, it burns too slow, and is nearly as wasteful; for a great quantity of it then
goes to the dust-hole without having been lighted at all.
An incorrect opinion is often entertained, that the real quantity of coal contained in a sack
is lessened by separating or screening the small from the round coals; but we must
recollect, that any compact body occupies less space than is required to contain the same
matter, reduced to smaller irregular pieces, or to powder.—Now the screening only takes
away the finest dusty part of the coals, and admits more small pieces of round coals to be
filled into the sack.
Nothing can be more perfectly devoid of common sense, and wasteful and
slovenly at the same time, than the manner in which chimney fires, where
coals are burnt, are commonly managed by servants. They throw on a load
of (perhaps all small) coals at once, through which the flame is hours in
making its way; and frequently it is not without much care and trouble that
the fire is prevented from going quite out. During this time no heat is
communicated to the room; and, what is still worse, the throat of the
chimney being occupied merely by a heavy dense vapour, not possessed of
any heating power, and, consequently, not having much elasticity, the warm
air of the room finds less difficulty in forcing its way up the chimney and
escaping, than when the fire burns bright, and the coal-gas is ignited. And it
happens not unfrequently, especially in chimnies and fire-places ill-
the fire almost the whole of the small coal passes through the bars; and consequently a
great deal goes to the dust-hole without being burnt at all. To prove this, we need only take
a shovel full of ashes and put them into a pail, and then pouring water over them, which
being gently run off, will carry away nearly all the light and burnt parts: and leave an
astonishing quantity of bright unburnt coal, which has escaped from the fire-place, in
consequence of being small.
When the grate of the fire-place is large, and the small coals are thrown behind; or when
we can have patience enough to bear the cold for an hour or two, or contrive to have the
fire lighted a long time before we want it, the small coal may be of some use, but the fire
made with it is never strong, nor so bright; and does not burn so long as a fire made with
large or round coals: it often requires the help of the poker, and produces a great quantity
of breeze.
The loss in the use of small coals is more considerable to the poor, who cannot keep large
fires. When they want their breakfast or dinner, the time they can spare is limited; and to
have their water sooner boiling, or their meals quicker ready; they must make use of the
poker, and lose a great deal of coal. This fact is so evident, that any body who wishes to
make the experiment before recommended, will find that much more bright coal goes to
the dust-hole of the poor man, than to the dust-hole of a rich family, where, the fire-place
being large, the small coal has more chance of burning.
The loss is still greater to the poor, in consequence of the inferior sorts of coal which are
sold to them. If it is the light sort, it burns too quick, and they consume double the quantity;
if the strong sort, it burns too slow, and is nearly as wasteful; for a great quantity of it then
goes to the dust-hole without having been lighted at all.
An incorrect opinion is often entertained, that the real quantity of coal contained in a sack
is lessened by separating or screening the small from the round coals; but we must
recollect, that any compact body occupies less space than is required to contain the same
matter, reduced to smaller irregular pieces, or to powder.—Now the screening only takes
away the finest dusty part of the coals, and admits more small pieces of round coals to be
filled into the sack.
Nothing can be more perfectly devoid of common sense, and wasteful and
slovenly at the same time, than the manner in which chimney fires, where
coals are burnt, are commonly managed by servants. They throw on a load
of (perhaps all small) coals at once, through which the flame is hours in
making its way; and frequently it is not without much care and trouble that
the fire is prevented from going quite out. During this time no heat is
communicated to the room; and, what is still worse, the throat of the
chimney being occupied merely by a heavy dense vapour, not possessed of
any heating power, and, consequently, not having much elasticity, the warm
air of the room finds less difficulty in forcing its way up the chimney and
escaping, than when the fire burns bright, and the coal-gas is ignited. And it
happens not unfrequently, especially in chimnies and fire-places ill-
Page 83
constructed, that this current of warm air from the room which presses into
the chimney, crossing upon the current of heavy smoke and aqueous vapour
which escapes slowly from the fire, obstructs it in its ascent, and beats it
back into the room. Hence it is that chimnies so often smoke when too large
a quantity of fresh coals is put upon the fire. So many coals should never be
put on the fire at once as to prevent the free passage of the flame between
them, or to prevent them becoming quickly heated, so as to give out the
carburetted hidrogen gas which they are capable of furnishing, and to cause
it to be inflamed, In short, a fire should never be smothered: and when
attention is paid to the quantity of coals put on, there is little use for the
poker; and this circumstance will contribute much to cleanliness, and the
preservation of furniture.
The author of a paper in the Plain Dealer asserts, that, of the various
perversions of abilities, there is none that makes a human being more
ridiculous, than that of attempting to stir a fire without judgment; to prevent
which he lays down the following rules:—1. Stirring of a fire is of use,
because it makes a hollow where, the air being rarefied by the adjacent heat,
the surrounding air rushes into this hollow, and gives life and support to the
fire, and carries the flame with it. 2. Never stir a fire when fresh coals are
laid on, particularly when they are very small, because they immediately
fall into the hollow place, and therefore ruin the fire. 3. Always keep the
bottom bars clear. 4. Never begin to stir the fire at the top, unless when the
bottom is quite clear, and the top only wants breaking.
There is one subject more on which it is necessary to speak.—In the present
instance, the public has been alarmed by representations that the general
adoption of gas-lights would expose us to innumerable accidents, from the
inflammable nature of the gas, and the explosion of the apparatus in which
it is prepared, or the bursting of the pipes by which it is conveyed. But there
is no ground for such fears.
Those who are familiar with the subject will readily allow, that there is no
more risk in the action of a gas-light machinery, properly constructed, than
there is in the action of a steam-engine, built on just principles.
The manufacture of the coal-gas requires nothing more than what the most
ignorant person, with a common degree of care and attention, is competent
the chimney, crossing upon the current of heavy smoke and aqueous vapour
which escapes slowly from the fire, obstructs it in its ascent, and beats it
back into the room. Hence it is that chimnies so often smoke when too large
a quantity of fresh coals is put upon the fire. So many coals should never be
put on the fire at once as to prevent the free passage of the flame between
them, or to prevent them becoming quickly heated, so as to give out the
carburetted hidrogen gas which they are capable of furnishing, and to cause
it to be inflamed, In short, a fire should never be smothered: and when
attention is paid to the quantity of coals put on, there is little use for the
poker; and this circumstance will contribute much to cleanliness, and the
preservation of furniture.
The author of a paper in the Plain Dealer asserts, that, of the various
perversions of abilities, there is none that makes a human being more
ridiculous, than that of attempting to stir a fire without judgment; to prevent
which he lays down the following rules:—1. Stirring of a fire is of use,
because it makes a hollow where, the air being rarefied by the adjacent heat,
the surrounding air rushes into this hollow, and gives life and support to the
fire, and carries the flame with it. 2. Never stir a fire when fresh coals are
laid on, particularly when they are very small, because they immediately
fall into the hollow place, and therefore ruin the fire. 3. Always keep the
bottom bars clear. 4. Never begin to stir the fire at the top, unless when the
bottom is quite clear, and the top only wants breaking.
There is one subject more on which it is necessary to speak.—In the present
instance, the public has been alarmed by representations that the general
adoption of gas-lights would expose us to innumerable accidents, from the
inflammable nature of the gas, and the explosion of the apparatus in which
it is prepared, or the bursting of the pipes by which it is conveyed. But there
is no ground for such fears.
Those who are familiar with the subject will readily allow, that there is no
more risk in the action of a gas-light machinery, properly constructed, than
there is in the action of a steam-engine, built on just principles.
The manufacture of the coal-gas requires nothing more than what the most
ignorant person, with a common degree of care and attention, is competent
Page 84
to perform. The heating of the gas-furnace, the charging of the retorts with
coal, the closing them up air-tight, the keeping them red-hot, and
discharging them again, are the only operations required in this art; and
these, surely, demand no more skill than a few practical lessons can teach to
the meanest capacity. The workman is not called upon to exercise his own
judgment, because, when the fire is properly managed, the evolution of the
gas goes on spontaneously, and without further care, till all the gas is
extricated from the coal.
No part of the machinery is liable to be out of order,—there are no cocks to
be turned, no valves to be regulated; nor can the operator derange the
apparatus but by the most violent efforts. And when the stock of gas is
prepared, we may depend on its lighting power as much as we depend on
the light to be obtained from a certain number of candles or oil-lamps.
The diversified experiments which have been made by different individuals,
unconnected with each other, have sufficiently established the perfect safety
of the new lights; and numerous manufactories might be named in which
the gas-lights have now been in use for upwards of seven years, where
nothing like an accident has occurred, though the apparatus in all of them is
entrusted to the most ignorant man.
It would be easy to state the causes which have given rise to some of those
accidents that have spread alarm amongst the public; but of this it is not my
business to speak at length. It is sufficient, on the present occasion, to state,
that those melancholy occurrences which have happened at some gas-light
establishments which I have had an opportunity of examining, were totally
occasioned by egregious failures committed in the construction of the
machinery. Thus, an explosion very lately took place in a manufactory
lighted with coal-gas, in consequence of a large quantity of gas escaping
into a building, where it mingled with common air, and was set on fire by
the approach of a lighted candle. That such an accident could happen, is an
evident proof that the machinery was erected by a bungler, unacquainted
with the most essential principles of this art; because such an accident
might have been effectually prevented, by adapting a waste pipe to the
gasometer and gasometer house. By this means, if more gas had been
prepared than the gasometer would contain, the superfluous quantity could
never have accumulated, but would have been transported out of the
coal, the closing them up air-tight, the keeping them red-hot, and
discharging them again, are the only operations required in this art; and
these, surely, demand no more skill than a few practical lessons can teach to
the meanest capacity. The workman is not called upon to exercise his own
judgment, because, when the fire is properly managed, the evolution of the
gas goes on spontaneously, and without further care, till all the gas is
extricated from the coal.
No part of the machinery is liable to be out of order,—there are no cocks to
be turned, no valves to be regulated; nor can the operator derange the
apparatus but by the most violent efforts. And when the stock of gas is
prepared, we may depend on its lighting power as much as we depend on
the light to be obtained from a certain number of candles or oil-lamps.
The diversified experiments which have been made by different individuals,
unconnected with each other, have sufficiently established the perfect safety
of the new lights; and numerous manufactories might be named in which
the gas-lights have now been in use for upwards of seven years, where
nothing like an accident has occurred, though the apparatus in all of them is
entrusted to the most ignorant man.
It would be easy to state the causes which have given rise to some of those
accidents that have spread alarm amongst the public; but of this it is not my
business to speak at length. It is sufficient, on the present occasion, to state,
that those melancholy occurrences which have happened at some gas-light
establishments which I have had an opportunity of examining, were totally
occasioned by egregious failures committed in the construction of the
machinery. Thus, an explosion very lately took place in a manufactory
lighted with coal-gas, in consequence of a large quantity of gas escaping
into a building, where it mingled with common air, and was set on fire by
the approach of a lighted candle. That such an accident could happen, is an
evident proof that the machinery was erected by a bungler, unacquainted
with the most essential principles of this art; because such an accident
might have been effectually prevented, by adapting a waste pipe to the
gasometer and gasometer house. By this means, if more gas had been
prepared than the gasometer would contain, the superfluous quantity could
never have accumulated, but would have been transported out of the
Page 85
building into the open air, in as an effectual manner as the waste-pipe of a
water cistern conveys away the superfluous quantity of water, when the
cistern is full. Such an expedient did not form part of the machinery.
Other instances might be named, where explosions have been occasioned
through egregious mistakes having been committed in the erection of the
gas-light machinery, were this a subject on which I meant to treat.
That the coal-gas, when mixed with a certain portion of common air, in
close vessels, may be inflamed by the contact of a lighted body, as has been
stated, page 98, is a fact sufficiently known. But the means of preventing
such an occurrence in the common application of gas-lights, are so simple,
easy, and effectual, that it would be ridiculous to dread danger where there
is nothing to be apprehended. In speaking thus of the safety of the gas-light
illumination, I do not mean to deny that no possible circumstances may
occur where the coal-gas may be the cause of accident. It is certain that the
gas, when suffered to accumulate in large quantities in close and confined
places, where there is no current of air, such as in cellars, vaults, &c. and
where it can mix with common air, and remain undisturbed, that it may be
liable to take fire when approached by a lighted body; but I do not see how
it is probable that such an accumulation of gas should take place in the
apartments of dwelling houses. The constant current of air which passes
continually through the rooms, is sufficient to prevent the possibility of
such an accumulation ever to take place. And with regard to the bursting of
the pipes which convey the gas, no accident can possibly happen from that
quarter; because the gas which passes through the whole range of pipes
sustains a pressure equal to the perpendicular weight of about one inch of
water only, and such a weight of course is insufficient to burst iron pipes.
Nor could the town when illuminated by gas-lights, be thrown suddenly
into darkness, as has been asserted might happen by the fracture of a main
pipe, supposing such an event should take place; because the lateral
branches, which supply the street-lamps and houses, are supplied by more
than one main; and the consequence of a fracture would be only an
extinction of the few lamps in the immediate vicinity of the broken pipe,
because the rest of the pipes, situated beyond the fracture, would continue
to be supplied with gas from the other mains, as will become obvious from
the sketch exhibited in the next page.
water cistern conveys away the superfluous quantity of water, when the
cistern is full. Such an expedient did not form part of the machinery.
Other instances might be named, where explosions have been occasioned
through egregious mistakes having been committed in the erection of the
gas-light machinery, were this a subject on which I meant to treat.
That the coal-gas, when mixed with a certain portion of common air, in
close vessels, may be inflamed by the contact of a lighted body, as has been
stated, page 98, is a fact sufficiently known. But the means of preventing
such an occurrence in the common application of gas-lights, are so simple,
easy, and effectual, that it would be ridiculous to dread danger where there
is nothing to be apprehended. In speaking thus of the safety of the gas-light
illumination, I do not mean to deny that no possible circumstances may
occur where the coal-gas may be the cause of accident. It is certain that the
gas, when suffered to accumulate in large quantities in close and confined
places, where there is no current of air, such as in cellars, vaults, &c. and
where it can mix with common air, and remain undisturbed, that it may be
liable to take fire when approached by a lighted body; but I do not see how
it is probable that such an accumulation of gas should take place in the
apartments of dwelling houses. The constant current of air which passes
continually through the rooms, is sufficient to prevent the possibility of
such an accumulation ever to take place. And with regard to the bursting of
the pipes which convey the gas, no accident can possibly happen from that
quarter; because the gas which passes through the whole range of pipes
sustains a pressure equal to the perpendicular weight of about one inch of
water only, and such a weight of course is insufficient to burst iron pipes.
Nor could the town when illuminated by gas-lights, be thrown suddenly
into darkness, as has been asserted might happen by the fracture of a main
pipe, supposing such an event should take place; because the lateral
branches, which supply the street-lamps and houses, are supplied by more
than one main; and the consequence of a fracture would be only an
extinction of the few lamps in the immediate vicinity of the broken pipe,
because the rest of the pipes, situated beyond the fracture, would continue
to be supplied with gas from the other mains, as will become obvious from
the sketch exhibited in the next page.
Page 86
Main pipe, leading from the Gas-light station or apparatus,
situated in Brick Lane, near Old St.[34]
M
a
i
n
p
i
p
e
,
l
e
a
d
i
n
g
f
r
[34] The gasometer at this place is equal in capacity to 22000 cubic feet. o
m
[35] The capacity of the gasometer here is equal to 15928 cubic feet. t
h
[36] At this station the gasometer is equal in capacity to 14808 cubic feet.
e
g
a
The black lines represent the gas-light mains, or largest pipes, from which s
the smaller pipes branch off: they are connected with each other at lthe
places marked A B C; and the dotted lines represent the smaller mains,i or
g
collateral branches before-mentioned. The main pipes are all furnished with h
valves, or cocks, placed at about 100 feet distant from each other. Now t let
us suppose that a main pipe, in any part of the street marked in the sketch, a
p
Pall Mall, should break, it is evident, on mere inspection, that the gas which p
is passing through the main in the Strand, and which is also connected with a
the main in the Haymarket, Piccadilly, and Coventry Street, would continue r
a
to supply the broken pipe, and the valve nearest to the fracture being shut, t
would prevent the loss of any considerable quantity of gas, and the few u
s
lamps situated between the two valves and the fracture would therefore only ,
become extinguished. o
r
s
situated in Brick Lane, near Old St.[34]
M
a
i
n
p
i
p
e
,
l
e
a
d
i
n
g
f
r
[34] The gasometer at this place is equal in capacity to 22000 cubic feet. o
m
[35] The capacity of the gasometer here is equal to 15928 cubic feet. t
h
[36] At this station the gasometer is equal in capacity to 14808 cubic feet.
e
g
a
The black lines represent the gas-light mains, or largest pipes, from which s
the smaller pipes branch off: they are connected with each other at lthe
places marked A B C; and the dotted lines represent the smaller mains,i or
g
collateral branches before-mentioned. The main pipes are all furnished with h
valves, or cocks, placed at about 100 feet distant from each other. Now t let
us suppose that a main pipe, in any part of the street marked in the sketch, a
p
Pall Mall, should break, it is evident, on mere inspection, that the gas which p
is passing through the main in the Strand, and which is also connected with a
the main in the Haymarket, Piccadilly, and Coventry Street, would continue r
a
to supply the broken pipe, and the valve nearest to the fracture being shut, t
would prevent the loss of any considerable quantity of gas, and the few u
s
lamps situated between the two valves and the fracture would therefore only ,
become extinguished. o
r
s
Page 87
t
Further, let us suppose a main pipe should break in Piccadilly; in that case,
a
the valve being shut on each side of the fracture, the gas would be suppliedt
from the mains in the Haymarket and St. James’s Street. And the same i
effect would be produced in any part of the town, supplied with gas-pipes. o
n
Besides all this, in the statement thus far given, we have assumed that , all
the gas-light mains are supplied with gas from one manufacturing station a
only, but which in reality is not the case. The range of pipes that convey tthe
N
gas is connected with three gas-light establishments, situated at different o
parts of the town; and the gas which is supplied from these stationsr is
t
connected with the whole system of pipes in the streets.[37] If, therefore, one
o
of the manufactories should be annihilated, it would make no difference, n
because the lights would be amply supplied from the other two F
manufacturing stations. Hence it is obvious, that the fracture of any of althe
gas-light mains, or even the total destruction of one or more of gthe
manufactories themselves, would be attended with no serious consequence; a
and as the system of lighting with gas becomes more extended, tethe
manufactories, or stations for supplying it, will also be multiplied, to give
.
[35]
effect and security to the whole.
Main pipe, leading from the gaslight apparatus, or station,
in Westminster.[36]
Further, let us suppose a main pipe should break in Piccadilly; in that case,
a
the valve being shut on each side of the fracture, the gas would be suppliedt
from the mains in the Haymarket and St. James’s Street. And the same i
effect would be produced in any part of the town, supplied with gas-pipes. o
n
Besides all this, in the statement thus far given, we have assumed that , all
the gas-light mains are supplied with gas from one manufacturing station a
only, but which in reality is not the case. The range of pipes that convey tthe
N
gas is connected with three gas-light establishments, situated at different o
parts of the town; and the gas which is supplied from these stationsr is
t
connected with the whole system of pipes in the streets.[37] If, therefore, one
o
of the manufactories should be annihilated, it would make no difference, n
because the lights would be amply supplied from the other two F
manufacturing stations. Hence it is obvious, that the fracture of any of althe
gas-light mains, or even the total destruction of one or more of gthe
manufactories themselves, would be attended with no serious consequence; a
and as the system of lighting with gas becomes more extended, tethe
manufactories, or stations for supplying it, will also be multiplied, to give
.
[35]
effect and security to the whole.
Main pipe, leading from the gaslight apparatus, or station,
in Westminster.[36]
Page 88
[37] As shown in the sketch.
In fact, no danger can arise from the application of gas-lights in any way, but what is common to candle-light, and
lamps of all kinds, and is the fault of none of them. Even in this case the gas-lights are less hazardous. There is no
risk of those accidents which often happen from the guttering or burning down of candles, or from carelessly
snuffing them. The gas-light lamps and burners must necessarily be fixed to one place, and therefore cannot fall, or
otherwise become deranged, without being immediately extinguished. Besides, the gas-light flames emit no sparks,
nor are any embers detached from them. As a proof of the comparative safety of the gas-lights, it need only be
stated, that the Fire-offices engage themselves to insure cotton-mills, and other public works, at a less premium,
where gas-lights are used, than in the case of any other lights.[38] The excessive expence of insurance arising from
the numerous candles employed in most of the first rate manufactories, and the combustible nature of the structure
of the buildings; the great difficulty of retrieving the injury resulting to a well-organised business, from the
accidental destruction of the machinery, are objects alone sufficient to furnish the strongest economical, as well as
political recommendations, for the adoption of the new lights in all manufactories where work is done by candle-
light.
[38] Since the preceding pages have been printed, I have seen a self-extinguishing gas-lamp, invented by Mr. Clegg. This lamp is so
constructed, that the gas cannot flow to the burner, when the flame becomes extinguished. If, therefore, the lamp should be blown out, and
the stop-cock which supplies the gas be left open, the extinction of the flame will effectually shut the valve. The action of this lamp
depends upon the expansibility of a metallic rod, heated by the flame of the lamp, and thus keeping open the valve, whereas, when the
lamp is extinguished, and the rod becomes cold, it contracts to its natural dimensions, and, by that means, effectually closes the valve. The
same engineer has invented a machine, which both measures and registers, in the absence of the observer, the quantity of gas delivered by
any pipe communicating with a gas-light main. The machine occupies a space of about two feet by one foot, and, if put up in a room,
house, or other place, where gas is burnt, will, at any time, by mere inspection, give an account of the quantity of gas consumed in that
place during any given time. On the present occasion, it would not become me to say more on these subjects, which, no doubt, Mr. Clegg
will make known to the public; I shall only remark, that these contrivances do signal honour to the talents and abilities of the inventor;
and that they will render the greatest services to those who are engaged in the gas-light illumination.
After considering the facts so far detailed, many other advantages, connected with the gas-light illumination, will
naturally suggest themselves to the reader. I have endeavoured merely to point out the leading characters of the
new lights, as they are at present. Ingenious men may speculate from what has been done to what remains to be
effected, which, no doubt, will embrace objects of the greatest utility and most extended national importance. The
public attention is awakened to the new properties of coal, and will not rest till they are extensively applied to
economical purposes. The consequence will be, a considerable defalcation in the revenue. For, in proportion as the
gas-lights are more or less generally adopted in all towns of the country, the consumption of oil and tallow will be
diminished, and the impost on those articles become less productive; and when this takes place, Government, no
doubt, will share in the profits, by levying a tax on the new lights. The Exchequer will thus have nothing to fear; as
one branch of the revenue fails, another, and a more productive one, will supply its place.
Upon the whole, when we reflect that the object of the gas-light illumination is to open a source of national wealth,
of which nothing can deprive us, to create, we may almost say, new articles of value, its friends cannot be thought
guilty of great presumption, if they look forward with confidence to the successful extension of this new art of
civil economy; and if, contrary to all expectations, the effects of jealousy and prejudice should, in some respect or
other, continue here and there its influence against this new art of procuring light, a firm perseverance of its
application must at length remove that ignorance which alone can give them birth.
TABULAR VIEW,
EXHIBITING
The quantity of Gas, Coke, Tar, Pitch, Essential Oil, and Ammoniacal Liquor, obtainable from a given quantity
of Coal; together with an Estimate of the quantity of Coal necessary to produce a quantity of Gas, capable of
yielding a Light equal in duration of time and intensity to that produced by Tallow Candles of different kinds.
Cost of Coal. Weight of Coal. Produce of Gas, in cubic feet
Mini- Maxi- Aver-
Min. Max. Aver. Min. Max. Aver.
mum. mum. age.
One Chal. - 40s to 60s — 50s 2,800 to 3,136 — 2,968 8,906 to 11,872 — 10,388[
of Coal,
In fact, no danger can arise from the application of gas-lights in any way, but what is common to candle-light, and
lamps of all kinds, and is the fault of none of them. Even in this case the gas-lights are less hazardous. There is no
risk of those accidents which often happen from the guttering or burning down of candles, or from carelessly
snuffing them. The gas-light lamps and burners must necessarily be fixed to one place, and therefore cannot fall, or
otherwise become deranged, without being immediately extinguished. Besides, the gas-light flames emit no sparks,
nor are any embers detached from them. As a proof of the comparative safety of the gas-lights, it need only be
stated, that the Fire-offices engage themselves to insure cotton-mills, and other public works, at a less premium,
where gas-lights are used, than in the case of any other lights.[38] The excessive expence of insurance arising from
the numerous candles employed in most of the first rate manufactories, and the combustible nature of the structure
of the buildings; the great difficulty of retrieving the injury resulting to a well-organised business, from the
accidental destruction of the machinery, are objects alone sufficient to furnish the strongest economical, as well as
political recommendations, for the adoption of the new lights in all manufactories where work is done by candle-
light.
[38] Since the preceding pages have been printed, I have seen a self-extinguishing gas-lamp, invented by Mr. Clegg. This lamp is so
constructed, that the gas cannot flow to the burner, when the flame becomes extinguished. If, therefore, the lamp should be blown out, and
the stop-cock which supplies the gas be left open, the extinction of the flame will effectually shut the valve. The action of this lamp
depends upon the expansibility of a metallic rod, heated by the flame of the lamp, and thus keeping open the valve, whereas, when the
lamp is extinguished, and the rod becomes cold, it contracts to its natural dimensions, and, by that means, effectually closes the valve. The
same engineer has invented a machine, which both measures and registers, in the absence of the observer, the quantity of gas delivered by
any pipe communicating with a gas-light main. The machine occupies a space of about two feet by one foot, and, if put up in a room,
house, or other place, where gas is burnt, will, at any time, by mere inspection, give an account of the quantity of gas consumed in that
place during any given time. On the present occasion, it would not become me to say more on these subjects, which, no doubt, Mr. Clegg
will make known to the public; I shall only remark, that these contrivances do signal honour to the talents and abilities of the inventor;
and that they will render the greatest services to those who are engaged in the gas-light illumination.
After considering the facts so far detailed, many other advantages, connected with the gas-light illumination, will
naturally suggest themselves to the reader. I have endeavoured merely to point out the leading characters of the
new lights, as they are at present. Ingenious men may speculate from what has been done to what remains to be
effected, which, no doubt, will embrace objects of the greatest utility and most extended national importance. The
public attention is awakened to the new properties of coal, and will not rest till they are extensively applied to
economical purposes. The consequence will be, a considerable defalcation in the revenue. For, in proportion as the
gas-lights are more or less generally adopted in all towns of the country, the consumption of oil and tallow will be
diminished, and the impost on those articles become less productive; and when this takes place, Government, no
doubt, will share in the profits, by levying a tax on the new lights. The Exchequer will thus have nothing to fear; as
one branch of the revenue fails, another, and a more productive one, will supply its place.
Upon the whole, when we reflect that the object of the gas-light illumination is to open a source of national wealth,
of which nothing can deprive us, to create, we may almost say, new articles of value, its friends cannot be thought
guilty of great presumption, if they look forward with confidence to the successful extension of this new art of
civil economy; and if, contrary to all expectations, the effects of jealousy and prejudice should, in some respect or
other, continue here and there its influence against this new art of procuring light, a firm perseverance of its
application must at length remove that ignorance which alone can give them birth.
TABULAR VIEW,
EXHIBITING
The quantity of Gas, Coke, Tar, Pitch, Essential Oil, and Ammoniacal Liquor, obtainable from a given quantity
of Coal; together with an Estimate of the quantity of Coal necessary to produce a quantity of Gas, capable of
yielding a Light equal in duration of time and intensity to that produced by Tallow Candles of different kinds.
Cost of Coal. Weight of Coal. Produce of Gas, in cubic feet
Mini- Maxi- Aver-
Min. Max. Aver. Min. Max. Aver.
mum. mum. age.
One Chal. - 40s to 60s — 50s 2,800 to 3,136 — 2,968 8,906 to 11,872 — 10,388[
of Coal,
Page 89
from 25
to 28 cwt.
One Ton 30s to 48s — 38s 6d 2,240 6,720 to 8,960 — 7,840
One Sack 3s 4d to 5s — 4s 2d 233 to 261 — 247 741 to 988 — 814
One Bushel 1s 2d to 1s 8d — 1s 5d 78 to 87 — 821⁄2 247 to 330 — 290
One Peck 31⁄2 to 5d — 41⁄4 191⁄2 to 211⁄4 — 201⁄4 61 to 82 — 711
One Pound 1⁄4 1 3 to 4 — 31
Coke.—One chaldron of coal, from 25 to 28 cwt. gives 11⁄4 to 1½ chaldron of Coke.
Tar.—One chaldron of coal, from 25 to 28 cwt. gives from 150 to 180lb. of Tar,[39] or 15 to 18 ale gallons
Ammoniacal Liquor.—One chaldron of coal, gives from 220 to 240lb. of Ammoniacal Liquor, or 22 to 24
[39]1000lb. of Coal-Tar afford by distillation, from 260 to 265lb. of Essential Oil, or Naphtha. 1000lb. of Coal-Tar produce by mere
evaporation, from 460 to 480lb. of Pitch.
Tabular View, exhibiting the illuminating power of Coal-Gas, compared with the illuminating power of Tallow
Candles of different sizes.
One chaldron of Coal produces, according to weight and quality,
Burning. Candles. 12 to 1lb. 6 to 1lb.
Cubic feet of Gas. Average. 1 hour = 21,000 = 10,500
From 9,000 to 12,000 10,500 2 hours = 10,500 = 5,250
6,000 8,000 7,000 3 ditto = 7,000 = 3,500
4,500 6,000 5,250 4 ditto = 5,250 = 2,625
3,600 4,800 4,400 5 ditto = 4,400 = 2,200
3,000 4,000 3,500 6 ditto = 3,500 = 1,750
2,571 3,428 3,005 7 ditto = 3,005 = 1,502
2,250 3,000 2,625 8 ditto = 2,625 = 1,312
2,000 2,666 2,333 9 ditto = 2,333 = 1,166
1,800 2,100 2,100 10 ditto = 2,100 = 1,050
1,636 2,191 1,913 11 ditto = 1,913 = 956
1,500 2,000 1,750 12 ditto = 1,750 = 875
1,384 1,846 1,615 13 ditto = 1,615 = 807
1,285 1,714 1,499 14 ditto = 1,499 = 749
1,200 1,600 1,400 15 ditto = 1,400 = 700
1,125 1,500 1,312 16 ditto = 1,312 = 656
1,058 1,111 1,234 17 ditto = 1,234 = 617
1,000 1,333 1,166 18 ditto = 1,166 = 583
947 1,263 1,105 19 ditto = 1,105 = 552
900 1,200 1,050 20 ditto = 1,050 = 525
857 1,143 1,000 21 ditto = 1,000 = 500
818 1,095 956 22 ditto = 956 = 478
783 1,044 913 23 ditto = 913 = 456
750 1,000 875 21 ditto = 875 = 437
N. B. If it be required to know, for how many hours one pound, or one peck, or one bushel, or one sack, of coal
will produce Gas Light equal to that of a certain number of well-snuffed Tallow Candles, the proportion of each of
the average weights of a pound, peck, bushel, or sack, to that of the average weight of a chaldron of coal, is as
follows:
1 lb. = 2968th part of a chaldron.
One peck 20 = 148th ditto.
One bushel 82 = 36th ditto.
to 28 cwt.
One Ton 30s to 48s — 38s 6d 2,240 6,720 to 8,960 — 7,840
One Sack 3s 4d to 5s — 4s 2d 233 to 261 — 247 741 to 988 — 814
One Bushel 1s 2d to 1s 8d — 1s 5d 78 to 87 — 821⁄2 247 to 330 — 290
One Peck 31⁄2 to 5d — 41⁄4 191⁄2 to 211⁄4 — 201⁄4 61 to 82 — 711
One Pound 1⁄4 1 3 to 4 — 31
Coke.—One chaldron of coal, from 25 to 28 cwt. gives 11⁄4 to 1½ chaldron of Coke.
Tar.—One chaldron of coal, from 25 to 28 cwt. gives from 150 to 180lb. of Tar,[39] or 15 to 18 ale gallons
Ammoniacal Liquor.—One chaldron of coal, gives from 220 to 240lb. of Ammoniacal Liquor, or 22 to 24
[39]1000lb. of Coal-Tar afford by distillation, from 260 to 265lb. of Essential Oil, or Naphtha. 1000lb. of Coal-Tar produce by mere
evaporation, from 460 to 480lb. of Pitch.
Tabular View, exhibiting the illuminating power of Coal-Gas, compared with the illuminating power of Tallow
Candles of different sizes.
One chaldron of Coal produces, according to weight and quality,
Burning. Candles. 12 to 1lb. 6 to 1lb.
Cubic feet of Gas. Average. 1 hour = 21,000 = 10,500
From 9,000 to 12,000 10,500 2 hours = 10,500 = 5,250
6,000 8,000 7,000 3 ditto = 7,000 = 3,500
4,500 6,000 5,250 4 ditto = 5,250 = 2,625
3,600 4,800 4,400 5 ditto = 4,400 = 2,200
3,000 4,000 3,500 6 ditto = 3,500 = 1,750
2,571 3,428 3,005 7 ditto = 3,005 = 1,502
2,250 3,000 2,625 8 ditto = 2,625 = 1,312
2,000 2,666 2,333 9 ditto = 2,333 = 1,166
1,800 2,100 2,100 10 ditto = 2,100 = 1,050
1,636 2,191 1,913 11 ditto = 1,913 = 956
1,500 2,000 1,750 12 ditto = 1,750 = 875
1,384 1,846 1,615 13 ditto = 1,615 = 807
1,285 1,714 1,499 14 ditto = 1,499 = 749
1,200 1,600 1,400 15 ditto = 1,400 = 700
1,125 1,500 1,312 16 ditto = 1,312 = 656
1,058 1,111 1,234 17 ditto = 1,234 = 617
1,000 1,333 1,166 18 ditto = 1,166 = 583
947 1,263 1,105 19 ditto = 1,105 = 552
900 1,200 1,050 20 ditto = 1,050 = 525
857 1,143 1,000 21 ditto = 1,000 = 500
818 1,095 956 22 ditto = 956 = 478
783 1,044 913 23 ditto = 913 = 456
750 1,000 875 21 ditto = 875 = 437
N. B. If it be required to know, for how many hours one pound, or one peck, or one bushel, or one sack, of coal
will produce Gas Light equal to that of a certain number of well-snuffed Tallow Candles, the proportion of each of
the average weights of a pound, peck, bushel, or sack, to that of the average weight of a chaldron of coal, is as
follows:
1 lb. = 2968th part of a chaldron.
One peck 20 = 148th ditto.
One bushel 82 = 36th ditto.
Page 90
One sack 248 = 12th ditto.
Rule.—Divide with either of the above parts of weight, the number of lights opposite to their hours, and the
product will be the number of lights burning for the same number of hours.
Example.—To know how many lights one peck of coal will give for six hours, divide the 148th part in 3,500,
opposite to the number of six hours, the product is almost 24 lights. The same rule holds good for any given
quantity or number of pounds of coal, in a chaldron, to find how many lights, or candles, 12 to the lb. or 6 to the lb.
they will give for a given number of hours.
DESCRIPTION
OF
THE GAS-LIGHT APPARATUS.
PLATE I.
Exhibits a perspective view of a gas-light apparatus,[40] for lighting factories, or small districts of houses. It
consists of the following parts: which may be considered separately.
[40] This apparatus was erected by Mr. Clegg, and is now in action at Mr. Ackerman’s establishment, in this metropolis.
Fig. 1. The Retort Furnace, for distilling the coals. It is built of brick-work. The bricks which are exposed to the
immediate action of the fire, are Welch tumps, or fire-bricks; they are bedded in clay, or Windsor loam.
Fig. 2. The Tar Cistern, to collect the coal-tar, and other condensible products obtained during the distillation of
the coals. It is a cast-iron hollow cylinder, closed at the top with a cast-iron cover, which has a very small hole to
allow the air to escape as the liquid enters into the vessel.
Fig. 3. The Lime Machine, for purifying the crude coal-gas, and to render it fit for use. The construction of this
machine will be explained in plate VII. It is put together of cast-iron plates.
Fig. 4. The Gasometer, for collecting and preserving the purified gas, and for distributing and applying it as
occasion may require. It consists of two principal parts—namely, a large interior vessel closed at the top and open
at the bottom, made of sheet iron, designed to contain the gas, and an outer cistern or vessel, of rather greater
capacity, constructed of cast-iron plates, in which the former vessel is suspended. The latter contains the water by
which the gas is confined. The interior vessel which contains the gas is suspended by chains hung over wheels or
pullies, to which weights are attached, so as to be just sufficient to balance the weight of the gasometer, all but a
small difference, and allowing its slow descent in the manner which is found as nearly adapted as can be to the
proper supply of the lamps. The weight of the chains must be equal to the specific gravity of the material of which
the gasometer is composed, so as to compensate accurately for the quantity of water which the gasometer
displaces, or what is the same, it must be equal to the loss of weight which the gasometer sustains, when immersed
in the water; and the counterpoise weight must be equal (or nearly so) to the absolute weight of the gasometer.
The action of these different parts of the apparatus will be obvious from the following explanation:
A, A, are two iron retorts, placed horizontally, and side by side, in the furnace; the mouth of the retorts where the
coals are introduced, projects into an arched chamber, situated in front of the furnace, as shewn in the drawing by
the broken down brick-work. The object of suffering the mouth of the retorts to project into a separate chamber, is
merely to discharge with convenience the red hot coke from the retorts when the process is at an end; the coke
being suffered to fall to the bottom of the chamber, where it cools, without becoming troublesome to the operator.
It may be removed from this fire-safe chamber by the door represented at the end view of the furnace.
When the operation commences, the inner vessel of the gasometer, fig. 4 is sunk down, to expel the air which it
contains to a level with the exterior vessel, or outer cistern, of the gasometer; and, consequently, becomes filled
with water. As the distillation of the coal in the retorts proceeds, the liquid and gazeous products evolved from the
coals are transmitted by means of the perpendicular syphon pipes B, B, into the horizontal pipe or main condenser
Rule.—Divide with either of the above parts of weight, the number of lights opposite to their hours, and the
product will be the number of lights burning for the same number of hours.
Example.—To know how many lights one peck of coal will give for six hours, divide the 148th part in 3,500,
opposite to the number of six hours, the product is almost 24 lights. The same rule holds good for any given
quantity or number of pounds of coal, in a chaldron, to find how many lights, or candles, 12 to the lb. or 6 to the lb.
they will give for a given number of hours.
DESCRIPTION
OF
THE GAS-LIGHT APPARATUS.
PLATE I.
Exhibits a perspective view of a gas-light apparatus,[40] for lighting factories, or small districts of houses. It
consists of the following parts: which may be considered separately.
[40] This apparatus was erected by Mr. Clegg, and is now in action at Mr. Ackerman’s establishment, in this metropolis.
Fig. 1. The Retort Furnace, for distilling the coals. It is built of brick-work. The bricks which are exposed to the
immediate action of the fire, are Welch tumps, or fire-bricks; they are bedded in clay, or Windsor loam.
Fig. 2. The Tar Cistern, to collect the coal-tar, and other condensible products obtained during the distillation of
the coals. It is a cast-iron hollow cylinder, closed at the top with a cast-iron cover, which has a very small hole to
allow the air to escape as the liquid enters into the vessel.
Fig. 3. The Lime Machine, for purifying the crude coal-gas, and to render it fit for use. The construction of this
machine will be explained in plate VII. It is put together of cast-iron plates.
Fig. 4. The Gasometer, for collecting and preserving the purified gas, and for distributing and applying it as
occasion may require. It consists of two principal parts—namely, a large interior vessel closed at the top and open
at the bottom, made of sheet iron, designed to contain the gas, and an outer cistern or vessel, of rather greater
capacity, constructed of cast-iron plates, in which the former vessel is suspended. The latter contains the water by
which the gas is confined. The interior vessel which contains the gas is suspended by chains hung over wheels or
pullies, to which weights are attached, so as to be just sufficient to balance the weight of the gasometer, all but a
small difference, and allowing its slow descent in the manner which is found as nearly adapted as can be to the
proper supply of the lamps. The weight of the chains must be equal to the specific gravity of the material of which
the gasometer is composed, so as to compensate accurately for the quantity of water which the gasometer
displaces, or what is the same, it must be equal to the loss of weight which the gasometer sustains, when immersed
in the water; and the counterpoise weight must be equal (or nearly so) to the absolute weight of the gasometer.
The action of these different parts of the apparatus will be obvious from the following explanation:
A, A, are two iron retorts, placed horizontally, and side by side, in the furnace; the mouth of the retorts where the
coals are introduced, projects into an arched chamber, situated in front of the furnace, as shewn in the drawing by
the broken down brick-work. The object of suffering the mouth of the retorts to project into a separate chamber, is
merely to discharge with convenience the red hot coke from the retorts when the process is at an end; the coke
being suffered to fall to the bottom of the chamber, where it cools, without becoming troublesome to the operator.
It may be removed from this fire-safe chamber by the door represented at the end view of the furnace.
When the operation commences, the inner vessel of the gasometer, fig. 4 is sunk down, to expel the air which it
contains to a level with the exterior vessel, or outer cistern, of the gasometer; and, consequently, becomes filled
with water. As the distillation of the coal in the retorts proceeds, the liquid and gazeous products evolved from the
coals are transmitted by means of the perpendicular syphon pipes B, B, into the horizontal pipe or main condenser
Page 91
C, with which they are connected. The liquid which is distilled, collects in the pipe, or main condenser, C, where it
is retained until its quantity has risen so high as to discharge itself into the pipe D, which is connected with the
upper part of one of the extremities of the condenser, C. One of the extremities of the pipes, B, B, therefore become
immersed into the liquid contained in the main condenser or pipe C, whilst the vaporous or condensible fluid, after
having overcome the pressure there opposed to it, is transported into the pipe E, which, after passing in a serpentine
direction, E, E, &c. through the exterior vessel or cistern of the gasometer, terminates in the tar-vessel, fig. 2. Thus
the vaporous fluids are condensed by passing through the serpentine pipe, E, E, &c. and become deposited in the
tar-cistern, fig. 2; whilst the non-condensible or gazeous products are made to proceed by the pipe F, which
branches off from the pipe E, into the lime machine, fig. 3. In this apparatus the gas, as it is evolved from the coals,
comes into contact with slaked lime and water; the object of which is, to strip it of its sulphuretted hydrogen and
carbonic acid gas with which it always abounds, and to render it fit for illumination. This being accomplished, the
purified gas is conducted away out of the lime machine by means of the pipe G, into the perpendicular pipe H,
which branches up through the bottom of the gasometer cistern. The upper extremity of this pipe is covered, in the
manner of a hood, by a cylindrical vessel I, open at bottom, but partially immersed beneath the surface of the water
contained in the outer cistern of the gasometer, it is also perforated round near the lower edge with a number of
small holes. The gas, as it passes out of the pipe H, displaces the water from the receiver I, and escapes through the
small holes, and is thus made to pass through the water in the cistern, in which the hood of the pipe I, is partly
immersed, so as to expose a large surface to its action, that it may once more be washed, and deprived of all the
foreign gazeous products which might have escaped the action of the lime, whilst it was agitated with this
substance in the lime machine, fig. 3. After rising through the water in the gasometer cistern, it enters into the
gasometer, which then ascends as the gas accumulates in it.
In this manner the process proceeds, until the whole of the volatile products of the coal in the retort are
disengaged. The use of the gasometer is, partly to equalize the evolution of the gas which comes from the retort
more quickly at some time than others. When this happens, the vessel rises up to receive it, and when the stream
from the retort diminishes, the weight of the gasometer expels its contents, provided the main-cock be open. When
the process is finished, the retort is suffered to cool, and its lid is then removed to replenish it with coal. When the
main stop-cock is then opened, the gasometer descends, and the gas passes from the gasometer through the pipe K,
to the burners, or main pipe, which communicates with the gas burners or lamps. L, is a wooden tub or barrel,
containing the mixture of lime and water, for charging the lime machine; and into which the contents of the barrel,
L, may be conveyed by the curved pipe M, without admitting common air. N, N, is a water-pipe, to convey fresh
water into the gasometer cistern occasionally; because it is essential that the water used for washing and purifying
the gas should be changed for fresh as soon as it becomes dirty; and unless this is done, the gas will not be
perfectly purified by washing, but produce a disagreeable odour when burnt; the same holds good with regard to
the lime machine, the contents of which should be renewed occasionally. This pipe also conveys the necessary
water into the barrel, L. O, is a waste-pipe, to convey the water as it becomes impregnated with the impurities of the
gas, out of the gasometer cistern. P, is an agitator, to stir up the contents of the lime machine occasionally, Q, Q, are
two iron rods, which serve as stays to guide the motion of the gasometer. R, is an index, connected by means of a
shaft and pulley with the axis of one of the gasometer wheels. This index is graduated to the capacity of the cubical
contents of the gasometer, so as to indicate, by the rising and falling of the gasometer, its relative contents of gas
expressed in cubic feet. S, is the waste pipe of the lime machine, to remove the insoluble parts of the lime. T,
represents the iron cover, or lid, which is turned on the lathe, and ground air-tight, to close up the mouth of the
retort, so as to make readily an air-tight fitting. U is an iron wedge to secure the cover of the retort. The left-hand
retort in the design shows the retort closed up, and the cover, or lid of the mouth of it secured by means of the
wedge, in its place, so as to render the mouth of the retort perfectly air tight.
There is a safety valve attached to this gasometer which could not be represented in the drawing; and the object of
which is, to convey away any portion of gas that might happen to be produced by a careless operator, when the
gasometer is full, and which is thus prevented from accumulating in the place where the gasometer is erected. It is
represented in the right-hand corner of plate VII. where fig. 1 shows the edge of the gasometer; 2, the surface of
the water in the inside of the gasometer; 3, the surface of the water in the outside of the gasometer, or in the
cistern; 4, a pipe issuing from the lower edge of the gasometer, and surrounded at its upper extremity with a cup
marked 5; 6, the waste pipe, the mouth of which is immersed in water. It is obvious that, when the gasometer is
full, if an additional quantity of gas should be attempted to be put into it, it will be transported by means of the
pipe 4, into the waste-pipe 6; the upper extremity of which reaches out of the building, and there communicates
with the open air.
is retained until its quantity has risen so high as to discharge itself into the pipe D, which is connected with the
upper part of one of the extremities of the condenser, C. One of the extremities of the pipes, B, B, therefore become
immersed into the liquid contained in the main condenser or pipe C, whilst the vaporous or condensible fluid, after
having overcome the pressure there opposed to it, is transported into the pipe E, which, after passing in a serpentine
direction, E, E, &c. through the exterior vessel or cistern of the gasometer, terminates in the tar-vessel, fig. 2. Thus
the vaporous fluids are condensed by passing through the serpentine pipe, E, E, &c. and become deposited in the
tar-cistern, fig. 2; whilst the non-condensible or gazeous products are made to proceed by the pipe F, which
branches off from the pipe E, into the lime machine, fig. 3. In this apparatus the gas, as it is evolved from the coals,
comes into contact with slaked lime and water; the object of which is, to strip it of its sulphuretted hydrogen and
carbonic acid gas with which it always abounds, and to render it fit for illumination. This being accomplished, the
purified gas is conducted away out of the lime machine by means of the pipe G, into the perpendicular pipe H,
which branches up through the bottom of the gasometer cistern. The upper extremity of this pipe is covered, in the
manner of a hood, by a cylindrical vessel I, open at bottom, but partially immersed beneath the surface of the water
contained in the outer cistern of the gasometer, it is also perforated round near the lower edge with a number of
small holes. The gas, as it passes out of the pipe H, displaces the water from the receiver I, and escapes through the
small holes, and is thus made to pass through the water in the cistern, in which the hood of the pipe I, is partly
immersed, so as to expose a large surface to its action, that it may once more be washed, and deprived of all the
foreign gazeous products which might have escaped the action of the lime, whilst it was agitated with this
substance in the lime machine, fig. 3. After rising through the water in the gasometer cistern, it enters into the
gasometer, which then ascends as the gas accumulates in it.
In this manner the process proceeds, until the whole of the volatile products of the coal in the retort are
disengaged. The use of the gasometer is, partly to equalize the evolution of the gas which comes from the retort
more quickly at some time than others. When this happens, the vessel rises up to receive it, and when the stream
from the retort diminishes, the weight of the gasometer expels its contents, provided the main-cock be open. When
the process is finished, the retort is suffered to cool, and its lid is then removed to replenish it with coal. When the
main stop-cock is then opened, the gasometer descends, and the gas passes from the gasometer through the pipe K,
to the burners, or main pipe, which communicates with the gas burners or lamps. L, is a wooden tub or barrel,
containing the mixture of lime and water, for charging the lime machine; and into which the contents of the barrel,
L, may be conveyed by the curved pipe M, without admitting common air. N, N, is a water-pipe, to convey fresh
water into the gasometer cistern occasionally; because it is essential that the water used for washing and purifying
the gas should be changed for fresh as soon as it becomes dirty; and unless this is done, the gas will not be
perfectly purified by washing, but produce a disagreeable odour when burnt; the same holds good with regard to
the lime machine, the contents of which should be renewed occasionally. This pipe also conveys the necessary
water into the barrel, L. O, is a waste-pipe, to convey the water as it becomes impregnated with the impurities of the
gas, out of the gasometer cistern. P, is an agitator, to stir up the contents of the lime machine occasionally, Q, Q, are
two iron rods, which serve as stays to guide the motion of the gasometer. R, is an index, connected by means of a
shaft and pulley with the axis of one of the gasometer wheels. This index is graduated to the capacity of the cubical
contents of the gasometer, so as to indicate, by the rising and falling of the gasometer, its relative contents of gas
expressed in cubic feet. S, is the waste pipe of the lime machine, to remove the insoluble parts of the lime. T,
represents the iron cover, or lid, which is turned on the lathe, and ground air-tight, to close up the mouth of the
retort, so as to make readily an air-tight fitting. U is an iron wedge to secure the cover of the retort. The left-hand
retort in the design shows the retort closed up, and the cover, or lid of the mouth of it secured by means of the
wedge, in its place, so as to render the mouth of the retort perfectly air tight.
There is a safety valve attached to this gasometer which could not be represented in the drawing; and the object of
which is, to convey away any portion of gas that might happen to be produced by a careless operator, when the
gasometer is full, and which is thus prevented from accumulating in the place where the gasometer is erected. It is
represented in the right-hand corner of plate VII. where fig. 1 shows the edge of the gasometer; 2, the surface of
the water in the inside of the gasometer; 3, the surface of the water in the outside of the gasometer, or in the
cistern; 4, a pipe issuing from the lower edge of the gasometer, and surrounded at its upper extremity with a cup
marked 5; 6, the waste pipe, the mouth of which is immersed in water. It is obvious that, when the gasometer is
full, if an additional quantity of gas should be attempted to be put into it, it will be transported by means of the
pipe 4, into the waste-pipe 6; the upper extremity of which reaches out of the building, and there communicates
with the open air.
Page 92
PLATE II.
Represents a Portable experimental Gas Apparatus for exhibiting, in the small way, the general nature of the gas-
light illumination.—It is described page 79.
PLATES III. IV. V.
Show designs of various kinds of Gas Lamps, Chandeliers, Candelabras, &c.—See pages 114, 118, 140.
PLATE VI.
Fig. 1. Exhibits a design of the gasometer framing, or skeleton, which serves to give stability and strength to the
gasometer. It consists of wooden frame work, marked A, A, A, interlaced with iron rods, B, B, B, &c. The whole
framing is so disposed that it will float in the cistern horizontally, and therefore keep the gasometer perfectly
steady and level with the surface of the water.
The rest of the sketches represent various kinds of gas pipes employed as mains for conveying the gas, and the
methods of connecting them.
Fig. 2. Represents a longitudinal section of a Spigot and Faucet Pipe. These kinds of pipes are applicable in most
cases as mains for conveying gas. A, is called the spigot, and B, the faucet. They are joined together, and made air
tight, by iron cement, the composition of which is as follows:
Take two ounces of sal ammoniac, one ounce of flowers of sulphur, and sixteen ounces of cast iron filings or
borings. Mix all well together, by rubbing them in a mortar, and keep the powder dry.
When the cement is wanted for use, take one part of the above powder, and twenty parts of clean iron borings or
filings, and blend them intimately by grinding them in a mortar. Wet the compound with water, and when brought
to a convenient consistence, apply it to the joints with a wooden or blunt iron spatula.
By a play of affinities, which those who are at all acquainted with chemistry will be at no loss to comprehend, a
degree of action and re-action takes place among the ingredients, and between them and the iron surfaces, which at
last causes the whole to unite as one mass. In fact, after a time, the mixture and the surfaces of the flanches become
a species of pyrites (holding a very large proportion of iron,) all the parts of which cohere strongly together.
The inner parts of the faucet ought to be no larger in diameter than just to fit the spigot. This supports the pipe,
independently of the cement, and prevents the risk of hurting the joint from any external stress. The inner faucet is
commonly made about 21⁄2 inches deep, and has the spigot inserted 11⁄2 inch into it. The practice of some workmen,
is to make the outer faucet, or that which contains the cement, six inches deep, for all pipes above six inches
diameter; and to make the faucets of all pipes below six inches, the same depth as the diameter of the pipes. It is
usual to make the space for the cement, all round the spigot, from 1 to 11⁄2 inch; that width is required, in order that
the cement may be firmly driven into the joint. When the space is very narrow, this cannot be done. On the other
hand, when too wide, there is a waste of cement, and a risk of injury from unequal expansion.
Fig. 3. Exhibits a profile view of these kinds of pipes when joined together. The spigot and faucet pipes are liable
to burst from the great expansion of the spigot, and the risk of this accident is increased by increasing the space
between the spigot and faucet, which requires to be filled with cement.
Fig. 4. Represents a longitudinal section of two flanch pipes, and the modes of connecting them. A and B, show the
parts of the pipes; and C and D, the flanches. These pipes are also joined together, and rendered air-tight, by
interposing between the flanches rope-yarn, hemp, or some other pliable material, and iron cement, and then
screwing up the faces of them by means of the bolts and screw nuts.
Fig. 5. Profile view of the same kind of pipes connected together, A and B, the pipes; C and D, the flanches; E and F,
the bolts.
Fig. 6. Represents the method of joining spigot and faucet pipes when they are to have a turn or angle. This method
is convenient when the place where the turn required to be made is previously known, and the pipes cast
Represents a Portable experimental Gas Apparatus for exhibiting, in the small way, the general nature of the gas-
light illumination.—It is described page 79.
PLATES III. IV. V.
Show designs of various kinds of Gas Lamps, Chandeliers, Candelabras, &c.—See pages 114, 118, 140.
PLATE VI.
Fig. 1. Exhibits a design of the gasometer framing, or skeleton, which serves to give stability and strength to the
gasometer. It consists of wooden frame work, marked A, A, A, interlaced with iron rods, B, B, B, &c. The whole
framing is so disposed that it will float in the cistern horizontally, and therefore keep the gasometer perfectly
steady and level with the surface of the water.
The rest of the sketches represent various kinds of gas pipes employed as mains for conveying the gas, and the
methods of connecting them.
Fig. 2. Represents a longitudinal section of a Spigot and Faucet Pipe. These kinds of pipes are applicable in most
cases as mains for conveying gas. A, is called the spigot, and B, the faucet. They are joined together, and made air
tight, by iron cement, the composition of which is as follows:
Take two ounces of sal ammoniac, one ounce of flowers of sulphur, and sixteen ounces of cast iron filings or
borings. Mix all well together, by rubbing them in a mortar, and keep the powder dry.
When the cement is wanted for use, take one part of the above powder, and twenty parts of clean iron borings or
filings, and blend them intimately by grinding them in a mortar. Wet the compound with water, and when brought
to a convenient consistence, apply it to the joints with a wooden or blunt iron spatula.
By a play of affinities, which those who are at all acquainted with chemistry will be at no loss to comprehend, a
degree of action and re-action takes place among the ingredients, and between them and the iron surfaces, which at
last causes the whole to unite as one mass. In fact, after a time, the mixture and the surfaces of the flanches become
a species of pyrites (holding a very large proportion of iron,) all the parts of which cohere strongly together.
The inner parts of the faucet ought to be no larger in diameter than just to fit the spigot. This supports the pipe,
independently of the cement, and prevents the risk of hurting the joint from any external stress. The inner faucet is
commonly made about 21⁄2 inches deep, and has the spigot inserted 11⁄2 inch into it. The practice of some workmen,
is to make the outer faucet, or that which contains the cement, six inches deep, for all pipes above six inches
diameter; and to make the faucets of all pipes below six inches, the same depth as the diameter of the pipes. It is
usual to make the space for the cement, all round the spigot, from 1 to 11⁄2 inch; that width is required, in order that
the cement may be firmly driven into the joint. When the space is very narrow, this cannot be done. On the other
hand, when too wide, there is a waste of cement, and a risk of injury from unequal expansion.
Fig. 3. Exhibits a profile view of these kinds of pipes when joined together. The spigot and faucet pipes are liable
to burst from the great expansion of the spigot, and the risk of this accident is increased by increasing the space
between the spigot and faucet, which requires to be filled with cement.
Fig. 4. Represents a longitudinal section of two flanch pipes, and the modes of connecting them. A and B, show the
parts of the pipes; and C and D, the flanches. These pipes are also joined together, and rendered air-tight, by
interposing between the flanches rope-yarn, hemp, or some other pliable material, and iron cement, and then
screwing up the faces of them by means of the bolts and screw nuts.
Fig. 5. Profile view of the same kind of pipes connected together, A and B, the pipes; C and D, the flanches; E and F,
the bolts.
Fig. 6. Represents the method of joining spigot and faucet pipes when they are to have a turn or angle. This method
is convenient when the place where the turn required to be made is previously known, and the pipes cast
Page 93
accordingly.
Fig. 7. Exhibits the method of connecting spigot and faucet pipes when they have a round turn. A and B, the
junctures of the pipes.
Fig. 8. Represents a longitudinal section of the mode of joining pipes by means of what is called a thimble joint.
The junctures of the pipes to be connected, are made air tight, as mentioned already, by iron cement. A, the thimble
or small cylinder, with projecting edges, which unites the pipes B, C.
Fig. 9. A thimble joint made in two parts, which is sometimes convenient to join pipes. The parts are joined
together by screw bolts, and nuts, in the usual manner.
Fig. 10. Section of the same.
Fig. 11. Represents a profile view of what is called the saddle joint. It is employed for taking off a branch-pipe.
The branch has a piece A B, formed on its end, and fits round one-half of the outside of the pipe from which it is to
proceed. C, is called the saddle, which fits round the other half of the pipe. The parts are secured together by screw
bolts, and iron cement. By this method a branch may be formed on any part of a gas-pipe, by cutting a hole there,
and applying the branch to that place. Where there is much risk of the inequality of expansion, the joints at certain
places, should be secured by a soft stuffing of hemp and tallow; but in most cases the joints may be made with iron
cement. Lead is frequently used for making the joints of gas pipes instead of iron cement, though cheaper and
more easy of repair. The galvanic action which takes place between the lead and iron, soon renders the joints leaky,
and the danger is increased by the unequal expansion of the two metals.
Fig. 12. Section of the saddle-joint.
Before the gas is suffered to enter into the pipe, they should be proved to be sound, by the usual process of forcing
water into them: The pipes serving as mains, are placed perfectly solid, so that they cannot give way; their course
should be rectilinear, having a descent of about 1 inch in 9 or 10 feet, to allow the water of condensation which
may be deposited from the gas by a change of temperature to collect readily at the lowermost part.
Fig. 13. Shows a reservoir for collecting the water of condensation which might accumulate in the pipes. It consists
of a receptacle, A, in which the water may pass; B, a branch-pipe closed at the top, by means of which the water
may be removed, by drawing it out with a syringe. This receptacle is placed in those situations where pipes incline
towards each other.
PLATE VII.
Exhibits a perpendicular section of a gas-light apparatus, calculated for lighting towns, or large districts of streets
and houses.
Fig. 1. The Retort Furnace. The retorts are placed over each other in one or more rows; so that a certain number of
them may be heated by separate fire-places. A, A, shows two of the retorts placed horizontally above each other; B,
the fire-place; C, the flue which causes the fire to circulate round the retorts so as to heat them equally in every
part; D, the opening of the flue where the fire passes into the chimney; E, the ash-pit; F, a chamber in front of the
retort furnace, into which the orifice or mouth of the retorts project; G, G, the doors of the chamber, to enable the
workmen to charge and discharge the retorts; H, a funnel shaped hole at the floor of the chamber F, through which
the red hot coke as it is discharged from the retorts passes into the arched vault I; K, the syphon tube; L, the
horizontal condenser[41]—the action of both of these pipes have been already explained, p. 168; M, main pipe,
which conveys the liquid substances from the condenser, to the tar cistern, fig. 3, and which conducts also the
gazeous products into the lime machine, fig. 2; N N, shows that part of the pipe which is interposed between the tar
cistern, fig. 3, and the condensing pipe M,—it passes in a serpentine direction along the inner sides of the
gasometer cistern, and, like the so-called worm in a distillatory apparatus, condenses the products which escape in
a vaporous state from the condenser L; O, shows the place where the serpentine pipe N N, passes again out of the
gasometer cistern, and its communication with the lime machine, fig. 2, and tar chamber, fig. 3. The action of the
lime machine is as follows: The liquid products evolved from the coal, having been deposited in the tar cistern, fig.
3, by means of the serpentine pipe N, N, the gazeous products which accompany it, are conveyed by means of the
pipe P, which branches out from the pipe O, into the interior receptacle of the lime machine marked Q, which
Fig. 7. Exhibits the method of connecting spigot and faucet pipes when they have a round turn. A and B, the
junctures of the pipes.
Fig. 8. Represents a longitudinal section of the mode of joining pipes by means of what is called a thimble joint.
The junctures of the pipes to be connected, are made air tight, as mentioned already, by iron cement. A, the thimble
or small cylinder, with projecting edges, which unites the pipes B, C.
Fig. 9. A thimble joint made in two parts, which is sometimes convenient to join pipes. The parts are joined
together by screw bolts, and nuts, in the usual manner.
Fig. 10. Section of the same.
Fig. 11. Represents a profile view of what is called the saddle joint. It is employed for taking off a branch-pipe.
The branch has a piece A B, formed on its end, and fits round one-half of the outside of the pipe from which it is to
proceed. C, is called the saddle, which fits round the other half of the pipe. The parts are secured together by screw
bolts, and iron cement. By this method a branch may be formed on any part of a gas-pipe, by cutting a hole there,
and applying the branch to that place. Where there is much risk of the inequality of expansion, the joints at certain
places, should be secured by a soft stuffing of hemp and tallow; but in most cases the joints may be made with iron
cement. Lead is frequently used for making the joints of gas pipes instead of iron cement, though cheaper and
more easy of repair. The galvanic action which takes place between the lead and iron, soon renders the joints leaky,
and the danger is increased by the unequal expansion of the two metals.
Fig. 12. Section of the saddle-joint.
Before the gas is suffered to enter into the pipe, they should be proved to be sound, by the usual process of forcing
water into them: The pipes serving as mains, are placed perfectly solid, so that they cannot give way; their course
should be rectilinear, having a descent of about 1 inch in 9 or 10 feet, to allow the water of condensation which
may be deposited from the gas by a change of temperature to collect readily at the lowermost part.
Fig. 13. Shows a reservoir for collecting the water of condensation which might accumulate in the pipes. It consists
of a receptacle, A, in which the water may pass; B, a branch-pipe closed at the top, by means of which the water
may be removed, by drawing it out with a syringe. This receptacle is placed in those situations where pipes incline
towards each other.
PLATE VII.
Exhibits a perpendicular section of a gas-light apparatus, calculated for lighting towns, or large districts of streets
and houses.
Fig. 1. The Retort Furnace. The retorts are placed over each other in one or more rows; so that a certain number of
them may be heated by separate fire-places. A, A, shows two of the retorts placed horizontally above each other; B,
the fire-place; C, the flue which causes the fire to circulate round the retorts so as to heat them equally in every
part; D, the opening of the flue where the fire passes into the chimney; E, the ash-pit; F, a chamber in front of the
retort furnace, into which the orifice or mouth of the retorts project; G, G, the doors of the chamber, to enable the
workmen to charge and discharge the retorts; H, a funnel shaped hole at the floor of the chamber F, through which
the red hot coke as it is discharged from the retorts passes into the arched vault I; K, the syphon tube; L, the
horizontal condenser[41]—the action of both of these pipes have been already explained, p. 168; M, main pipe,
which conveys the liquid substances from the condenser, to the tar cistern, fig. 3, and which conducts also the
gazeous products into the lime machine, fig. 2; N N, shows that part of the pipe which is interposed between the tar
cistern, fig. 3, and the condensing pipe M,—it passes in a serpentine direction along the inner sides of the
gasometer cistern, and, like the so-called worm in a distillatory apparatus, condenses the products which escape in
a vaporous state from the condenser L; O, shows the place where the serpentine pipe N N, passes again out of the
gasometer cistern, and its communication with the lime machine, fig. 2, and tar chamber, fig. 3. The action of the
lime machine is as follows: The liquid products evolved from the coal, having been deposited in the tar cistern, fig.
3, by means of the serpentine pipe N, N, the gazeous products which accompany it, are conveyed by means of the
pipe P, which branches out from the pipe O, into the interior receptacle of the lime machine marked Q, which
Page 94
consists of a vessel open at the bottom, and closed at the top, where it communicates with the pipe O. As the gas
accumulates in the interior part Q, of the lime machine, it is made to pass through the liquid which it contains,
namely, slaked lime and water; and escapes through appertures made in the horizontal partitions R, R, R, R, into the
outer vessel, S, of the lime machine and from thence it is conducted away by the pipe T, T, T, into the additional
washing apparatus, of the gasometer; fig. 4, the construction of this apparatus, greatly resembles the lime machine,
fig. 2, namely, V, is a water pipe, proceeding from a cistern U, placed 3 or 4 feet above the orifice of the pipe V; T,
T, is the gas-pipe, covered with a hood, marked W, and immersed in a small cistern, having horizontal perforated
shelves, like those in the lime machine—they fit close to the hood. The gas which enters the hood W, meets with a
shower of water delivered by the pipe V. The gas, as it passes through the holes in the horizontal partitions, is,
therefore, again washed and thoroughly purified from foreign gases which may have escaped the action of the lime
machine; Y, is a waste pipe, the lower extremity of which is sealed by being immersed in water,—it serves to carry
away the water delivered by the pipe V, as it has been acted on by the gas. The summary action of this gas
apparatus is, therefore, as follows: The liquid products obtained from the coal during the distillation are first
deposited in the main condenser L, by means of the pipe K, and from whence they cannot escape until a quantity of
tar has accumulated in it to a certain height, and by this means, one of the extremities of the pipes K, K, becomes
immersed and hermetically sealed by the liquid which the condenser L, contains. The liquid products, after having
accumulated to a certain height in the condenser, overflow the perpendicular portion which it contains, and
discharge themselves into the pipe M, from whence they are transported into the tar cistern, fig. 3, by means of the
system of pipes N, N, O, whilst the gazeous products are made to pass by means of the branch pipe P, into the lime
machine, fig. 2. From this part of the apparatus the gas passes through the pipe T, T, T, into the additional or
smaller washing apparatus placed upon a tressel in the cistern of the gasometer, where it is again exposed a second
time to the action of a current of fresh water; and from this vessel the gas ascends into the gasometer. The
gasometer is furnished with a pipe A, closed at the top, and fixed in one corner of the gasometer, but open at the
bottom; it includes another pipe marked B, which communicates with the main pipe leading to the burners, or place
where the gas is wanted. The pipe A, which slides over the pipe B, is perforated at the top, the gas passes through
these perforations and is thus made to enter into the pipe B, and disposed of as mentioned. C, C, is a tube of safety
adapted to the gasometer; its lower extremity remains sealed by the water in the cistern so long as the gasometer is
not overcharged with gas; but, if more gas should be made to enter the gasometer than it is destined to receive, this
pipe then delivers the gas into the funnel-shaped tube D, which reaches through the roof of the gasometer house,
and thus the superfluous quantity of gas is conveyed away into the open air.
[41] The condenser in this apparatus is placed at right angles to the row, or rows of retorts. It is furnished at one extremity with a partition
placed perpendicularly, and of a height equal to about one-half of the diameter of the condenser. The object of this partition is to prevent
the tar, &c. deposited in it, to seal the pipes K, K, and not to discharge itself into the pipe M, till this has been effected. The partition is seen
in the drawing.
The cylindrical vessel P, of fig. 3, surrounding the orifice of the pipe O, which delivers the tar into the tar cistern,
fig. 3, serves to keep this pipe constantly immersed into a portion of tar, so that the contents of the cistern may be
drawn off by the cock without admitting air into any part of the apparatus. The tar cistern has a small hole at the
top, to allow the air which it encloses to escape, as it becomes filled with tar and ammoniacal liquor. The main
condenser L, is placed, as shown in the drawing, higher than the level of the water in the gasometer cistern, to
allow a free descent of the distillatory liquids as they pass from this vessel along into the pipes M, N, O, &c. The
cistern of the gasometer, as well as the lime machine, and tar cistern, are constructed of cast iron plates, bolted and
cemented together with iron cement. The gasometer is made of sheet iron plates rivetted together—E, E, are two
iron stays—G, G, are friction wheels.
METHOD of correcting the relative pressure of the Gasometer, so as to cause the gas which it
contains to be uniformly of an equal density.[42]
[42] For this elegant contrivance we are also indebted to Mr. Clegg.
We have mentioned already that the pressure of the gas in the gasometer should be invariable, for it is obvious that
the weight of the gasometer is constantly increasing in proportion as it fills with gas, and rises out of the water—
see p. 88, and 167. To render its pressure uniform, we first take the absolute weight of that part of the gasometer
which becomes immersed in the water, and knowing the specific weight of the substance of which it is composed,
we divide its absolute weight by the specific weight of the substance of which it is composed; and this being done,
accumulates in the interior part Q, of the lime machine, it is made to pass through the liquid which it contains,
namely, slaked lime and water; and escapes through appertures made in the horizontal partitions R, R, R, R, into the
outer vessel, S, of the lime machine and from thence it is conducted away by the pipe T, T, T, into the additional
washing apparatus, of the gasometer; fig. 4, the construction of this apparatus, greatly resembles the lime machine,
fig. 2, namely, V, is a water pipe, proceeding from a cistern U, placed 3 or 4 feet above the orifice of the pipe V; T,
T, is the gas-pipe, covered with a hood, marked W, and immersed in a small cistern, having horizontal perforated
shelves, like those in the lime machine—they fit close to the hood. The gas which enters the hood W, meets with a
shower of water delivered by the pipe V. The gas, as it passes through the holes in the horizontal partitions, is,
therefore, again washed and thoroughly purified from foreign gases which may have escaped the action of the lime
machine; Y, is a waste pipe, the lower extremity of which is sealed by being immersed in water,—it serves to carry
away the water delivered by the pipe V, as it has been acted on by the gas. The summary action of this gas
apparatus is, therefore, as follows: The liquid products obtained from the coal during the distillation are first
deposited in the main condenser L, by means of the pipe K, and from whence they cannot escape until a quantity of
tar has accumulated in it to a certain height, and by this means, one of the extremities of the pipes K, K, becomes
immersed and hermetically sealed by the liquid which the condenser L, contains. The liquid products, after having
accumulated to a certain height in the condenser, overflow the perpendicular portion which it contains, and
discharge themselves into the pipe M, from whence they are transported into the tar cistern, fig. 3, by means of the
system of pipes N, N, O, whilst the gazeous products are made to pass by means of the branch pipe P, into the lime
machine, fig. 2. From this part of the apparatus the gas passes through the pipe T, T, T, into the additional or
smaller washing apparatus placed upon a tressel in the cistern of the gasometer, where it is again exposed a second
time to the action of a current of fresh water; and from this vessel the gas ascends into the gasometer. The
gasometer is furnished with a pipe A, closed at the top, and fixed in one corner of the gasometer, but open at the
bottom; it includes another pipe marked B, which communicates with the main pipe leading to the burners, or place
where the gas is wanted. The pipe A, which slides over the pipe B, is perforated at the top, the gas passes through
these perforations and is thus made to enter into the pipe B, and disposed of as mentioned. C, C, is a tube of safety
adapted to the gasometer; its lower extremity remains sealed by the water in the cistern so long as the gasometer is
not overcharged with gas; but, if more gas should be made to enter the gasometer than it is destined to receive, this
pipe then delivers the gas into the funnel-shaped tube D, which reaches through the roof of the gasometer house,
and thus the superfluous quantity of gas is conveyed away into the open air.
[41] The condenser in this apparatus is placed at right angles to the row, or rows of retorts. It is furnished at one extremity with a partition
placed perpendicularly, and of a height equal to about one-half of the diameter of the condenser. The object of this partition is to prevent
the tar, &c. deposited in it, to seal the pipes K, K, and not to discharge itself into the pipe M, till this has been effected. The partition is seen
in the drawing.
The cylindrical vessel P, of fig. 3, surrounding the orifice of the pipe O, which delivers the tar into the tar cistern,
fig. 3, serves to keep this pipe constantly immersed into a portion of tar, so that the contents of the cistern may be
drawn off by the cock without admitting air into any part of the apparatus. The tar cistern has a small hole at the
top, to allow the air which it encloses to escape, as it becomes filled with tar and ammoniacal liquor. The main
condenser L, is placed, as shown in the drawing, higher than the level of the water in the gasometer cistern, to
allow a free descent of the distillatory liquids as they pass from this vessel along into the pipes M, N, O, &c. The
cistern of the gasometer, as well as the lime machine, and tar cistern, are constructed of cast iron plates, bolted and
cemented together with iron cement. The gasometer is made of sheet iron plates rivetted together—E, E, are two
iron stays—G, G, are friction wheels.
METHOD of correcting the relative pressure of the Gasometer, so as to cause the gas which it
contains to be uniformly of an equal density.[42]
[42] For this elegant contrivance we are also indebted to Mr. Clegg.
We have mentioned already that the pressure of the gas in the gasometer should be invariable, for it is obvious that
the weight of the gasometer is constantly increasing in proportion as it fills with gas, and rises out of the water—
see p. 88, and 167. To render its pressure uniform, we first take the absolute weight of that part of the gasometer
which becomes immersed in the water, and knowing the specific weight of the substance of which it is composed,
we divide its absolute weight by the specific weight of the substance of which it is composed; and this being done,
Page 95
we make part of the chain, (measured at right angles from the axis of the wheels over which it passes downwards
towards the top of the gasometer,) which is equal to the length of that part of the gasometer which becomes
immersed in water, equal in weight to the specific gravity of the substance of which the gasometer is composed.
For example, let us suppose that the part of the gasometer which becomes immersed in water weighs 861 lb. and
that it is composed of sheet iron, the specific gravity of which, in round numbers, we will take to be 7. It is then
evident, that the part of the chain of the gasometer measured downward from the axis of the wheel over which it
passes, and which is equal in length to the height of the gasometer, must be loaded with a weight of, or must itself
weigh, 123lb. for this would be the weight of the water displaced by the gasometer; or let us suppose the
gasometer to be made of sheet copper, the specific weight of which (omitting decimals) is 8; and that the absolute
weight of the gasometer is 1792lbs. then the chain of the gasometer equal in length to the height of the gasometer,
immersed into the water must weigh 224lb. for this would be the weight of the quantity of water which the
gasometer displaces. This being accomplished by then adding or diminishing the absolute or balance weight of the
gasometer, any desired uniform pressure may be effected, and the same bulk of gas will always be of the same
specific gravity.
DIRECTIONS TO WORKMEN
ATTENDING
THE GAS-LIGHT APPARATUS[43].
[43] Copied from a printed direction drawn up by Mr. Clegg, for the use of workmen.
Particular care must be taken to make the joints of the mouth-pieces of the retorts perfectly air tight, which may be
done in the following manner:—Take some common clay, dry, pulverize, and sift it, then add as much water as will
make it into the consistency of treacle; make the mouth-piece and the lid of the retort clean, lay this luting thinly
over the turned part of the lid, press the lid so luted gently to the mouth-piece, and then secure it moderately, by
means of the iron wedge: if the workman observes this rule, he will never fail to make good joints; but if, on the
other hand, the operator is careless and neglects to remove the old luting, &c. from the turned or smooth part of the
mouth of the retort, and thereby cause a bad joint, the consequence will be the loss of a considerable quantity of
gas, and a very disagreeable smell and smoke.
The bridge or row of bricks of the flue C, of the retorts, should never be made hotter than a bright red, which may
be regulated by the door of the ash-pit being kept close shut when the fire is getting too hot. If the operator
neglects this, and suffers the fire-bricks to arrive at a bright white heat the retorts will soon be destroyed, and bad
gas be produced.
The gasometer should be well examined, at least once a week, to see if it leaks, by the following method, viz. Let
the main stop-cock be shut, then make a mark on the gasometer at the water’s edge when it is full or nearly of gas,
there being no gas coming from the retorts at the time, and if the mark sinks in the water, the gasometer leaks; to
find out the place, walk slowly round it, and you may perceive the leak by the smell, apply a lighted candle to the
part suspected, and if there be gas issuing from it, it will take fire, and perhaps appear like a small blue flame—
blow it out, and mark the place: thus proceed round the gasometer till you have found all the places; if you
perceive a smell, and yet cannot produce a flame in the part suspected, take a brush with a little thin white-lead
paint, and lay it on the part where you think the leak is, and, if it be there, the gas which escapes from the leak, will
immediately turn the paint brown. After the sides of the gasometer have been well examined, and secured by
dipping a piece of cloth about the size of a shilling, into some melted pitch, tempered with a little bees-wax and tar,
apply the cloth whilst hot to the place with the end of your finger, rubbing it till it is quite cold; next examine the
top of the gasometer in the same manner,—when it is about two feet high in the cistern, it will then be better to get
at. The water in the cistern should always be kept within 3 or four inches of the top, if suffered to sink much lower
without replenishing, the gas will not pass through a sufficient quantity of water, and oily particles will be apt to
condense in the pipes, to their great detriment.
The only thing to be observed in the place lighted is, that the lamps and pipes are not suffered to be touched on any
pretence whatever, but by the person entrusted with their care. When a lamp is not wanted, it must be completely
shut off from the pipe which supplies it, by a stop-cock provided for the purpose, and not opened again but when a
flame is held over it; not a lighted candle, as the tallow is liable to drop into the lamps; lighted paper is better.
towards the top of the gasometer,) which is equal to the length of that part of the gasometer which becomes
immersed in water, equal in weight to the specific gravity of the substance of which the gasometer is composed.
For example, let us suppose that the part of the gasometer which becomes immersed in water weighs 861 lb. and
that it is composed of sheet iron, the specific gravity of which, in round numbers, we will take to be 7. It is then
evident, that the part of the chain of the gasometer measured downward from the axis of the wheel over which it
passes, and which is equal in length to the height of the gasometer, must be loaded with a weight of, or must itself
weigh, 123lb. for this would be the weight of the water displaced by the gasometer; or let us suppose the
gasometer to be made of sheet copper, the specific weight of which (omitting decimals) is 8; and that the absolute
weight of the gasometer is 1792lbs. then the chain of the gasometer equal in length to the height of the gasometer,
immersed into the water must weigh 224lb. for this would be the weight of the quantity of water which the
gasometer displaces. This being accomplished by then adding or diminishing the absolute or balance weight of the
gasometer, any desired uniform pressure may be effected, and the same bulk of gas will always be of the same
specific gravity.
DIRECTIONS TO WORKMEN
ATTENDING
THE GAS-LIGHT APPARATUS[43].
[43] Copied from a printed direction drawn up by Mr. Clegg, for the use of workmen.
Particular care must be taken to make the joints of the mouth-pieces of the retorts perfectly air tight, which may be
done in the following manner:—Take some common clay, dry, pulverize, and sift it, then add as much water as will
make it into the consistency of treacle; make the mouth-piece and the lid of the retort clean, lay this luting thinly
over the turned part of the lid, press the lid so luted gently to the mouth-piece, and then secure it moderately, by
means of the iron wedge: if the workman observes this rule, he will never fail to make good joints; but if, on the
other hand, the operator is careless and neglects to remove the old luting, &c. from the turned or smooth part of the
mouth of the retort, and thereby cause a bad joint, the consequence will be the loss of a considerable quantity of
gas, and a very disagreeable smell and smoke.
The bridge or row of bricks of the flue C, of the retorts, should never be made hotter than a bright red, which may
be regulated by the door of the ash-pit being kept close shut when the fire is getting too hot. If the operator
neglects this, and suffers the fire-bricks to arrive at a bright white heat the retorts will soon be destroyed, and bad
gas be produced.
The gasometer should be well examined, at least once a week, to see if it leaks, by the following method, viz. Let
the main stop-cock be shut, then make a mark on the gasometer at the water’s edge when it is full or nearly of gas,
there being no gas coming from the retorts at the time, and if the mark sinks in the water, the gasometer leaks; to
find out the place, walk slowly round it, and you may perceive the leak by the smell, apply a lighted candle to the
part suspected, and if there be gas issuing from it, it will take fire, and perhaps appear like a small blue flame—
blow it out, and mark the place: thus proceed round the gasometer till you have found all the places; if you
perceive a smell, and yet cannot produce a flame in the part suspected, take a brush with a little thin white-lead
paint, and lay it on the part where you think the leak is, and, if it be there, the gas which escapes from the leak, will
immediately turn the paint brown. After the sides of the gasometer have been well examined, and secured by
dipping a piece of cloth about the size of a shilling, into some melted pitch, tempered with a little bees-wax and tar,
apply the cloth whilst hot to the place with the end of your finger, rubbing it till it is quite cold; next examine the
top of the gasometer in the same manner,—when it is about two feet high in the cistern, it will then be better to get
at. The water in the cistern should always be kept within 3 or four inches of the top, if suffered to sink much lower
without replenishing, the gas will not pass through a sufficient quantity of water, and oily particles will be apt to
condense in the pipes, to their great detriment.
The only thing to be observed in the place lighted is, that the lamps and pipes are not suffered to be touched on any
pretence whatever, but by the person entrusted with their care. When a lamp is not wanted, it must be completely
shut off from the pipe which supplies it, by a stop-cock provided for the purpose, and not opened again but when a
flame is held over it; not a lighted candle, as the tallow is liable to drop into the lamps; lighted paper is better.
Page 96
ESTIMATE
OF
THE PRICE
OF
A GAS-LIGHT APPARATUS,
IF ERECTED IN LONDON,
Capable of affording, every 24 hours, Light equal to 40,000 Tallow Candles, six in the pound, burning one hour.
£. s.
Gasometer, to contain 10,000 cubic feet of gas 236 0
Wheel-work, regulating chain, ballance-weight for ditto, with wooden framing 160 11
Wrought iron cistern for gasometer—36 feet wide, 24 feet long and 16 feet deep 500 0
(It would weigh about 16 tons.)
Wooden framing built around it, to secure ditto 150 0
Condenser, cistern and communicating pipes 126 0
Lime machine, made of cast iron plates 82 0
Gasometer-house, built of frame-work and weather-boarded 250 0
Twenty-four retorts set in brick-work, with furnaces for ditto, compleat 336 0
Sundries 100 0
£ 1940 11
A gas-light apparatus complete for work, capable of affording every twenty-four hours a quantity of light equal to
1,400 Argand’s Lamps, each lamp equal in intensity to six candles, six in the pound, burning for five hours, will
cost 3,500l. if erected in this metropolis.
LONDON Price List of the most essential articles[44] employed in the erection of a Gas-Light
apparatus.
[44] All the articles are warranted to be perfect and of the best kind. They are delivered free of expence at any wharf between London and
Westminster-bridge.
Sheet-iron pipes brazed.
s. d.
1⁄4 inch in diameter 0 4 a foot
3⁄8 ditto 0 4 ditto
1⁄2 ditto 0 5 ditto
5⁄8 ditto 0 6 ditto
3⁄4 ditto 0 61⁄2 ditto
7⁄8 ditto 7 ditto in 15
1 inch, ditto 0 7 ⁄2
1 ditto to 18
-
11⁄4 ditto 0 9 ditto feet
11⁄2 ditto 0 101⁄2 ditto lengths.
1 ⁄4 ditto
3 0 11 ditto
2 inch, ditto 1 11⁄2 ditto
21⁄4 ditto 1 4 ditto
21⁄2 ditto 1 5 ditto
3 inch, ditto 1 61⁄2 ditto
Copper pipes brazed ⁄4 inch
1 0 4 per foot
OF
THE PRICE
OF
A GAS-LIGHT APPARATUS,
IF ERECTED IN LONDON,
Capable of affording, every 24 hours, Light equal to 40,000 Tallow Candles, six in the pound, burning one hour.
£. s.
Gasometer, to contain 10,000 cubic feet of gas 236 0
Wheel-work, regulating chain, ballance-weight for ditto, with wooden framing 160 11
Wrought iron cistern for gasometer—36 feet wide, 24 feet long and 16 feet deep 500 0
(It would weigh about 16 tons.)
Wooden framing built around it, to secure ditto 150 0
Condenser, cistern and communicating pipes 126 0
Lime machine, made of cast iron plates 82 0
Gasometer-house, built of frame-work and weather-boarded 250 0
Twenty-four retorts set in brick-work, with furnaces for ditto, compleat 336 0
Sundries 100 0
£ 1940 11
A gas-light apparatus complete for work, capable of affording every twenty-four hours a quantity of light equal to
1,400 Argand’s Lamps, each lamp equal in intensity to six candles, six in the pound, burning for five hours, will
cost 3,500l. if erected in this metropolis.
LONDON Price List of the most essential articles[44] employed in the erection of a Gas-Light
apparatus.
[44] All the articles are warranted to be perfect and of the best kind. They are delivered free of expence at any wharf between London and
Westminster-bridge.
Sheet-iron pipes brazed.
s. d.
1⁄4 inch in diameter 0 4 a foot
3⁄8 ditto 0 4 ditto
1⁄2 ditto 0 5 ditto
5⁄8 ditto 0 6 ditto
3⁄4 ditto 0 61⁄2 ditto
7⁄8 ditto 7 ditto in 15
1 inch, ditto 0 7 ⁄2
1 ditto to 18
-
11⁄4 ditto 0 9 ditto feet
11⁄2 ditto 0 101⁄2 ditto lengths.
1 ⁄4 ditto
3 0 11 ditto
2 inch, ditto 1 11⁄2 ditto
21⁄4 ditto 1 4 ditto
21⁄2 ditto 1 5 ditto
3 inch, ditto 1 61⁄2 ditto
Copper pipes brazed ⁄4 inch
1 0 4 per foot
Page 97
Ditto, ditto, ditto 3⁄8 inch 0 51⁄2 ditto
Gas-light cockspur burners with stop-cock 2s 6d to 3s 6d
Argand’s lamps, with glass-holders, from 3s to 4s 6d
Cast-iron retorts, weighing 7 cwt. at 15s 6d per cwt £5 8 6
Mouth-piece for ditto, compleat 1 14 8
Cast-iron door frames for retort furnace 1 0 0
Furnace bars 10s. per cwt.
Sheet iron for gazometer (No. 23) 24s. per cwt.
Gazometer chains, 5d per lb.
Ballance weights [Plates] for gazometer, 9l 10s per ton.
Cast-iron cistern plates
----------------------- smaller size for lime machine, 18l per ton.
----------------------- middling size for tar cistern, 16l ditto
----------------------- largest size for gazometer cistern 14l ditto
Cast-iron flanch pipes 2-inch diameter, at 5s per yd. in 6 feet lengths
ditto 3 ditto 6s ditto 6 ditto
ditto 4 ditto 8s 6d ditto 9 ditto
ditto 5 ditto 10s ditto 9 ditto
ditto 6 ditto 12s ditto 9 ditto
ditto 7 ditto 13s 6d ditto 9 ditto
ditto 8
ditto 9
- 11l. 5s. per ton 9 ditto
ditto 10
ditto 11
1⁄2 inch nuts, screws and washers to put iron pipes together 7d. per lb
5⁄8 ditto 7d. ditto
3⁄4 ditto 6d. ditto
English bar-iron 13l. per ton
Best, ditto 18l. ditto
FINIS.
Gas-light cockspur burners with stop-cock 2s 6d to 3s 6d
Argand’s lamps, with glass-holders, from 3s to 4s 6d
Cast-iron retorts, weighing 7 cwt. at 15s 6d per cwt £5 8 6
Mouth-piece for ditto, compleat 1 14 8
Cast-iron door frames for retort furnace 1 0 0
Furnace bars 10s. per cwt.
Sheet iron for gazometer (No. 23) 24s. per cwt.
Gazometer chains, 5d per lb.
Ballance weights [Plates] for gazometer, 9l 10s per ton.
Cast-iron cistern plates
----------------------- smaller size for lime machine, 18l per ton.
----------------------- middling size for tar cistern, 16l ditto
----------------------- largest size for gazometer cistern 14l ditto
Cast-iron flanch pipes 2-inch diameter, at 5s per yd. in 6 feet lengths
ditto 3 ditto 6s ditto 6 ditto
ditto 4 ditto 8s 6d ditto 9 ditto
ditto 5 ditto 10s ditto 9 ditto
ditto 6 ditto 12s ditto 9 ditto
ditto 7 ditto 13s 6d ditto 9 ditto
ditto 8
ditto 9
- 11l. 5s. per ton 9 ditto
ditto 10
ditto 11
1⁄2 inch nuts, screws and washers to put iron pipes together 7d. per lb
5⁄8 ditto 7d. ditto
3⁄4 ditto 6d. ditto
English bar-iron 13l. per ton
Best, ditto 18l. ditto
FINIS.
Page 98
Larger image (345 kB)
Larger image (302 kB)
Larger image (302 kB)
Page 99
Transcriber’s notes
The entries in the Table of Contents do not always conform to the chapter and section
headings in the text. Both have been retained as in the original work.
The errata have already been incorporated in the text; the error mentioned as occurring
on page 24 actually occurs on page 22.
The original language, including inconsistencies in spelling, hyphenation,
punctuation, formatting, etc. has been retained, except as mentioned below.
The e-reader cover image has been created for this project, and is placed in the public
domain.
Unclear parts of the text have been checked against the on-line copy of this book of
the Eidgenössische Technische Hochschule Zürich.
Fractions like 1⁄2 and 1-10th have both been retained.
Page 90, Van Dieman, Troostwyck: Jan Rudolph Deiman and Adriaan Paets van
Troostwijk.
Changes made to the text:
Obvious punctuation and typographical errors have been corrected silently.
Some footnotes, tables and illustrations have been moved; some tables have been re-
arranged.
Other changes:
Page 23: any surfaces changed to any surface
Page 26: opening or shuting changed to opening or shutting
Page 47: A New changed to A new
Page 48: trafic changed to traffic; footnote [10]: corporated changed to incorporated
(cf. errata)
Page 53: This combustion changed to The combustion (cf. errata)
Page 64: Cleg changed to Clegg (cf. errata); footnote anchor [14] moved from next
page (cf. errata, footnote anchor *); communicates changed to communicated (cf.
errata)
Page 67: 1250 + 2 = 2500 changed to 1250 × 2 = 2500
Page 69: Mr. Lee changed to “Mr. Lee for consistency
Page 72: closing quote mark added to letter
Page 96: pure coal- changed to pure coal-gas
Page 102: sub acetate changed to sub-acetate
Page 118: ball 6 changed to ball b
Page 119: e, are changed to e e, are
Page 125: 180 degree changed to 180 degrees (cf. errata); footnote [28]: may he
compleatly changed to may be compleatly
Page 131: and make changed to and makes
Page 132: coal changed to coal-tar (cf. errata)
Page 158: Nortou Falgate changed to Norton Falgate; a about changed to about
Page 165, table: 10,509 changed to 10,500.
The entries in the Table of Contents do not always conform to the chapter and section
headings in the text. Both have been retained as in the original work.
The errata have already been incorporated in the text; the error mentioned as occurring
on page 24 actually occurs on page 22.
The original language, including inconsistencies in spelling, hyphenation,
punctuation, formatting, etc. has been retained, except as mentioned below.
The e-reader cover image has been created for this project, and is placed in the public
domain.
Unclear parts of the text have been checked against the on-line copy of this book of
the Eidgenössische Technische Hochschule Zürich.
Fractions like 1⁄2 and 1-10th have both been retained.
Page 90, Van Dieman, Troostwyck: Jan Rudolph Deiman and Adriaan Paets van
Troostwijk.
Changes made to the text:
Obvious punctuation and typographical errors have been corrected silently.
Some footnotes, tables and illustrations have been moved; some tables have been re-
arranged.
Other changes:
Page 23: any surfaces changed to any surface
Page 26: opening or shuting changed to opening or shutting
Page 47: A New changed to A new
Page 48: trafic changed to traffic; footnote [10]: corporated changed to incorporated
(cf. errata)
Page 53: This combustion changed to The combustion (cf. errata)
Page 64: Cleg changed to Clegg (cf. errata); footnote anchor [14] moved from next
page (cf. errata, footnote anchor *); communicates changed to communicated (cf.
errata)
Page 67: 1250 + 2 = 2500 changed to 1250 × 2 = 2500
Page 69: Mr. Lee changed to “Mr. Lee for consistency
Page 72: closing quote mark added to letter
Page 96: pure coal- changed to pure coal-gas
Page 102: sub acetate changed to sub-acetate
Page 118: ball 6 changed to ball b
Page 119: e, are changed to e e, are
Page 125: 180 degree changed to 180 degrees (cf. errata); footnote [28]: may he
compleatly changed to may be compleatly
Page 131: and make changed to and makes
Page 132: coal changed to coal-tar (cf. errata)
Page 158: Nortou Falgate changed to Norton Falgate; a about changed to about
Page 165, table: 10,509 changed to 10,500.
Page 100
*** END OF THE PROJECT GUTENBERG EBOOK A PRACTICAL
TREATISE ON GAS-LIGHT ***
Updated editions will replace the previous one—the old editions will be
renamed.
Creating the works from print editions not protected by U.S. copyright law
means that no one owns a United States copyright in these works, so the
Foundation (and you!) can copy and distribute it in the United States
without permission and without paying copyright royalties. Special rules,
set forth in the General Terms of Use part of this license, apply to copying
and distributing Project Gutenberg™ electronic works to protect the
PROJECT GUTENBERG™ concept and trademark. Project Gutenberg is a
registered trademark, and may not be used if you charge for an eBook,
except by following the terms of the trademark license, including paying
royalties for use of the Project Gutenberg trademark. If you do not charge
anything for copies of this eBook, complying with the trademark license is
very easy. You may use this eBook for nearly any purpose such as creation
of derivative works, reports, performances and research. Project Gutenberg
eBooks may be modified and printed and given away—you may do
practically ANYTHING in the United States with eBooks not protected by
U.S. copyright law. Redistribution is subject to the trademark license,
especially commercial redistribution.
START: FULL LICENSE
TREATISE ON GAS-LIGHT ***
Updated editions will replace the previous one—the old editions will be
renamed.
Creating the works from print editions not protected by U.S. copyright law
means that no one owns a United States copyright in these works, so the
Foundation (and you!) can copy and distribute it in the United States
without permission and without paying copyright royalties. Special rules,
set forth in the General Terms of Use part of this license, apply to copying
and distributing Project Gutenberg™ electronic works to protect the
PROJECT GUTENBERG™ concept and trademark. Project Gutenberg is a
registered trademark, and may not be used if you charge for an eBook,
except by following the terms of the trademark license, including paying
royalties for use of the Project Gutenberg trademark. If you do not charge
anything for copies of this eBook, complying with the trademark license is
very easy. You may use this eBook for nearly any purpose such as creation
of derivative works, reports, performances and research. Project Gutenberg
eBooks may be modified and printed and given away—you may do
practically ANYTHING in the United States with eBooks not protected by
U.S. copyright law. Redistribution is subject to the trademark license,
especially commercial redistribution.
START: FULL LICENSE
Page 101
THE FULL PROJECT GUTENBERG™ LICENSE
PLEASE READ THIS BEFORE YOU DISTRIBUTE OR USE THIS WORK
To protect the Project Gutenberg™ mission of promoting the free
distribution of electronic works, by using or distributing this work (or any
other work associated in any way with the phrase “Project Gutenberg”), you
agree to comply with all the terms of the Full Project Gutenberg License
available with this file or online at www.gutenberg.org/license.
Section 1. General Terms of Use and Redistributing
Project Gutenberg electronic works
1.A. By reading or using any part of this Project Gutenberg electronic work,
you indicate that you have read, understand, agree to and accept all the
terms of this license and intellectual property (trademark/copyright)
agreement. If you do not agree to abide by all the terms of this agreement,
you must cease using and return or destroy all copies of Project Gutenberg
electronic works in your possession. If you paid a fee for obtaining a copy
of or access to a Project Gutenberg electronic work and you do not agree to
be bound by the terms of this agreement, you may obtain a refund from the
person or entity to whom you paid the fee as set forth in paragraph 1.E.8.
1.B. “Project Gutenberg” is a registered trademark. It may only be used on
or associated in any way with an electronic work by people who agree to be
bound by the terms of this agreement. There are a few things that you can
do with most Project Gutenberg electronic works even without complying
with the full terms of this agreement. See paragraph 1.C below. There are a
lot of things you can do with Project Gutenberg electronic works if you
follow the terms of this agreement and help preserve free future access to
Project Gutenberg electronic works. See paragraph 1.E below.
1.C. The Project Gutenberg Literary Archive Foundation (“the Foundation”
or PGLAF), owns a compilation copyright in the collection of Project
Gutenberg electronic works. Nearly all the individual works in the
collection are in the public domain in the United States. If an individual
work is unprotected by copyright law in the United States and you are
PLEASE READ THIS BEFORE YOU DISTRIBUTE OR USE THIS WORK
To protect the Project Gutenberg™ mission of promoting the free
distribution of electronic works, by using or distributing this work (or any
other work associated in any way with the phrase “Project Gutenberg”), you
agree to comply with all the terms of the Full Project Gutenberg License
available with this file or online at www.gutenberg.org/license.
Section 1. General Terms of Use and Redistributing
Project Gutenberg electronic works
1.A. By reading or using any part of this Project Gutenberg electronic work,
you indicate that you have read, understand, agree to and accept all the
terms of this license and intellectual property (trademark/copyright)
agreement. If you do not agree to abide by all the terms of this agreement,
you must cease using and return or destroy all copies of Project Gutenberg
electronic works in your possession. If you paid a fee for obtaining a copy
of or access to a Project Gutenberg electronic work and you do not agree to
be bound by the terms of this agreement, you may obtain a refund from the
person or entity to whom you paid the fee as set forth in paragraph 1.E.8.
1.B. “Project Gutenberg” is a registered trademark. It may only be used on
or associated in any way with an electronic work by people who agree to be
bound by the terms of this agreement. There are a few things that you can
do with most Project Gutenberg electronic works even without complying
with the full terms of this agreement. See paragraph 1.C below. There are a
lot of things you can do with Project Gutenberg electronic works if you
follow the terms of this agreement and help preserve free future access to
Project Gutenberg electronic works. See paragraph 1.E below.
1.C. The Project Gutenberg Literary Archive Foundation (“the Foundation”
or PGLAF), owns a compilation copyright in the collection of Project
Gutenberg electronic works. Nearly all the individual works in the
collection are in the public domain in the United States. If an individual
work is unprotected by copyright law in the United States and you are
Page 102
located in the United States, we do not claim a right to prevent you from
copying, distributing, performing, displaying or creating derivative works
based on the work as long as all references to Project Gutenberg are
removed. Of course, we hope that you will support the Project Gutenberg
mission of promoting free access to electronic works by freely sharing
Project Gutenberg works in compliance with the terms of this agreement for
keeping the Project Gutenberg name associated with the work. You can
easily comply with the terms of this agreement by keeping this work in the
same format with its attached full Project Gutenberg License when you
share it without charge with others.
1.D. The copyright laws of the place where you are located also govern
what you can do with this work. Copyright laws in most countries are in a
constant state of change. If you are outside the United States, check the
laws of your country in addition to the terms of this agreement before
downloading, copying, displaying, performing, distributing or creating
derivative works based on this work or any other Project Gutenberg work.
The Foundation makes no representations concerning the copyright status
of any work in any country other than the United States.
1.E. Unless you have removed all references to Project Gutenberg:
1.E.1. The following sentence, with active links to, or other immediate
access to, the full Project Gutenberg License must appear prominently
whenever any copy of a Project Gutenberg work (any work on which the
phrase “Project Gutenberg” appears, or with which the phrase “Project
Gutenberg” is associated) is accessed, displayed, performed, viewed, copied
or distributed:
This eBook is for the use of anyone anywhere in the United States and most other parts of the world
at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it
under the terms of the Project Gutenberg™ License included with this eBook or online at
www.gutenberg.org. If you are not located in the United States, you will have to check the laws of
the country where you are located before using this eBook.
1.E.2. If an individual Project Gutenberg electronic work is derived from
texts not protected by U.S. copyright law (does not contain a notice
indicating that it is posted with permission of the copyright holder), the
work can be copied and distributed to anyone in the United States without
copying, distributing, performing, displaying or creating derivative works
based on the work as long as all references to Project Gutenberg are
removed. Of course, we hope that you will support the Project Gutenberg
mission of promoting free access to electronic works by freely sharing
Project Gutenberg works in compliance with the terms of this agreement for
keeping the Project Gutenberg name associated with the work. You can
easily comply with the terms of this agreement by keeping this work in the
same format with its attached full Project Gutenberg License when you
share it without charge with others.
1.D. The copyright laws of the place where you are located also govern
what you can do with this work. Copyright laws in most countries are in a
constant state of change. If you are outside the United States, check the
laws of your country in addition to the terms of this agreement before
downloading, copying, displaying, performing, distributing or creating
derivative works based on this work or any other Project Gutenberg work.
The Foundation makes no representations concerning the copyright status
of any work in any country other than the United States.
1.E. Unless you have removed all references to Project Gutenberg:
1.E.1. The following sentence, with active links to, or other immediate
access to, the full Project Gutenberg License must appear prominently
whenever any copy of a Project Gutenberg work (any work on which the
phrase “Project Gutenberg” appears, or with which the phrase “Project
Gutenberg” is associated) is accessed, displayed, performed, viewed, copied
or distributed:
This eBook is for the use of anyone anywhere in the United States and most other parts of the world
at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it
under the terms of the Project Gutenberg™ License included with this eBook or online at
www.gutenberg.org. If you are not located in the United States, you will have to check the laws of
the country where you are located before using this eBook.
1.E.2. If an individual Project Gutenberg electronic work is derived from
texts not protected by U.S. copyright law (does not contain a notice
indicating that it is posted with permission of the copyright holder), the
work can be copied and distributed to anyone in the United States without
Page 103
paying any fees or charges. If you are redistributing or providing access to a
work with the phrase “Project Gutenberg” associated with or appearing on
the work, you must comply either with the requirements of paragraphs
1.E.1 through 1.E.7 or obtain permission for the use of the work and the
Project Gutenberg trademark as set forth in paragraphs 1.E.8 or 1.E.9.
1.E.3. If an individual Project Gutenberg electronic work is posted with the
permission of the copyright holder, your use and distribution must comply
with both paragraphs 1.E.1 through 1.E.7 and any additional terms imposed
by the copyright holder. Additional terms will be linked to the Project
Gutenberg License for all works posted with the permission of the
copyright holder found at the beginning of this work.
1.E.4. Do not unlink or detach or remove the full Project Gutenberg License
terms from this work, or any files containing a part of this work or any
other work associated with Project Gutenberg.
1.E.5. Do not copy, display, perform, distribute or redistribute this
electronic work, or any part of this electronic work, without prominently
displaying the sentence set forth in paragraph 1.E.1 with active links or
immediate access to the full terms of the Project Gutenberg License.
1.E.6. You may convert to and distribute this work in any binary,
compressed, marked up, nonproprietary or proprietary form, including any
word processing or hypertext form. However, if you provide access to or
distribute copies of a Project Gutenberg work in a format other than “Plain
Vanilla ASCII” or other format used in the official version posted on the
official Project Gutenberg website (www.gutenberg.org), you must, at no
additional cost, fee or expense to the user, provide a copy, a means of
exporting a copy, or a means of obtaining a copy upon request, of the work
in its original “Plain Vanilla ASCII” or other form. Any alternate format
must include the full Project Gutenberg License as specified in paragraph
1.E.1.
1.E.7. Do not charge a fee for access to, viewing, displaying, performing,
copying or distributing any Project Gutenberg works unless you comply
with paragraph 1.E.8 or 1.E.9.
work with the phrase “Project Gutenberg” associated with or appearing on
the work, you must comply either with the requirements of paragraphs
1.E.1 through 1.E.7 or obtain permission for the use of the work and the
Project Gutenberg trademark as set forth in paragraphs 1.E.8 or 1.E.9.
1.E.3. If an individual Project Gutenberg electronic work is posted with the
permission of the copyright holder, your use and distribution must comply
with both paragraphs 1.E.1 through 1.E.7 and any additional terms imposed
by the copyright holder. Additional terms will be linked to the Project
Gutenberg License for all works posted with the permission of the
copyright holder found at the beginning of this work.
1.E.4. Do not unlink or detach or remove the full Project Gutenberg License
terms from this work, or any files containing a part of this work or any
other work associated with Project Gutenberg.
1.E.5. Do not copy, display, perform, distribute or redistribute this
electronic work, or any part of this electronic work, without prominently
displaying the sentence set forth in paragraph 1.E.1 with active links or
immediate access to the full terms of the Project Gutenberg License.
1.E.6. You may convert to and distribute this work in any binary,
compressed, marked up, nonproprietary or proprietary form, including any
word processing or hypertext form. However, if you provide access to or
distribute copies of a Project Gutenberg work in a format other than “Plain
Vanilla ASCII” or other format used in the official version posted on the
official Project Gutenberg website (www.gutenberg.org), you must, at no
additional cost, fee or expense to the user, provide a copy, a means of
exporting a copy, or a means of obtaining a copy upon request, of the work
in its original “Plain Vanilla ASCII” or other form. Any alternate format
must include the full Project Gutenberg License as specified in paragraph
1.E.1.
1.E.7. Do not charge a fee for access to, viewing, displaying, performing,
copying or distributing any Project Gutenberg works unless you comply
with paragraph 1.E.8 or 1.E.9.
Page 104
1.E.8. You may charge a reasonable fee for copies of or providing access to
or distributing Project Gutenberg electronic works provided that:
• You pay a royalty fee of 20% of the gross profits you derive from the
use of Project Gutenberg works calculated using the method you
already use to calculate your applicable taxes. The fee is owed to the
owner of the Project Gutenberg trademark, but he has agreed to donate
royalties under this paragraph to the Project Gutenberg Literary
Archive Foundation. Royalty payments must be paid within 60 days
following each date on which you prepare (or are legally required to
prepare) your periodic tax returns. Royalty payments should be clearly
marked as such and sent to the Project Gutenberg Literary Archive
Foundation at the address specified in Section 4, “Information about
donations to the Project Gutenberg Literary Archive Foundation.”
• You provide a full refund of any money paid by a user who notifies
you in writing (or by e-mail) within 30 days of receipt that s/he does
not agree to the terms of the full Project Gutenberg™ License. You
must require such a user to return or destroy all copies of the works
possessed in a physical medium and discontinue all use of and all
access to other copies of Project Gutenberg™ works.
• You provide, in accordance with paragraph 1.F.3, a full refund of any
money paid for a work or a replacement copy, if a defect in the
electronic work is discovered and reported to you within 90 days of
receipt of the work.
• You comply with all other terms of this agreement for free distribution
of Project Gutenberg™ works.
1.E.9. If you wish to charge a fee or distribute a Project Gutenberg™
electronic work or group of works on different terms than are set forth in
this agreement, you must obtain permission in writing from the Project
Gutenberg Literary Archive Foundation, the manager of the Project
Gutenberg™ trademark. Contact the Foundation as set forth in Section 3
below.
1.F.
or distributing Project Gutenberg electronic works provided that:
• You pay a royalty fee of 20% of the gross profits you derive from the
use of Project Gutenberg works calculated using the method you
already use to calculate your applicable taxes. The fee is owed to the
owner of the Project Gutenberg trademark, but he has agreed to donate
royalties under this paragraph to the Project Gutenberg Literary
Archive Foundation. Royalty payments must be paid within 60 days
following each date on which you prepare (or are legally required to
prepare) your periodic tax returns. Royalty payments should be clearly
marked as such and sent to the Project Gutenberg Literary Archive
Foundation at the address specified in Section 4, “Information about
donations to the Project Gutenberg Literary Archive Foundation.”
• You provide a full refund of any money paid by a user who notifies
you in writing (or by e-mail) within 30 days of receipt that s/he does
not agree to the terms of the full Project Gutenberg™ License. You
must require such a user to return or destroy all copies of the works
possessed in a physical medium and discontinue all use of and all
access to other copies of Project Gutenberg™ works.
• You provide, in accordance with paragraph 1.F.3, a full refund of any
money paid for a work or a replacement copy, if a defect in the
electronic work is discovered and reported to you within 90 days of
receipt of the work.
• You comply with all other terms of this agreement for free distribution
of Project Gutenberg™ works.
1.E.9. If you wish to charge a fee or distribute a Project Gutenberg™
electronic work or group of works on different terms than are set forth in
this agreement, you must obtain permission in writing from the Project
Gutenberg Literary Archive Foundation, the manager of the Project
Gutenberg™ trademark. Contact the Foundation as set forth in Section 3
below.
1.F.
Page 105
1.F.1. Project Gutenberg volunteers and employees expend considerable
effort to identify, do copyright research on, transcribe and proofread works
not protected by U.S. copyright law in creating the Project Gutenberg™
collection. Despite these efforts, Project Gutenberg™ electronic works, and
the medium on which they may be stored, may contain “Defects,” such as,
but not limited to, incomplete, inaccurate or corrupt data, transcription
errors, a copyright or other intellectual property infringement, a defective or
damaged disk or other medium, a computer virus, or computer codes that
damage or cannot be read by your equipment.
1.F.2. LIMITED WARRANTY, DISCLAIMER OF DAMAGES - Except
for the “Right of Replacement or Refund” described in paragraph 1.F.3, the
Project Gutenberg Literary Archive Foundation, the owner of the Project
Gutenberg™ trademark, and any other party distributing a Project
Gutenberg™ electronic work under this agreement, disclaim all liability to
you for damages, costs and expenses, including legal fees. YOU AGREE
THAT YOU HAVE NO REMEDIES FOR NEGLIGENCE, STRICT
LIABILITY, BREACH OF WARRANTY OR BREACH OF CONTRACT
EXCEPT THOSE PROVIDED IN PARAGRAPH 1.F.3. YOU AGREE
THAT THE FOUNDATION, THE TRADEMARK OWNER, AND ANY
DISTRIBUTOR UNDER THIS AGREEMENT WILL NOT BE LIABLE
TO YOU FOR ACTUAL, DIRECT, INDIRECT, CONSEQUENTIAL,
PUNITIVE OR INCIDENTAL DAMAGES EVEN IF YOU GIVE
NOTICE OF THE POSSIBILITY OF SUCH DAMAGE.
1.F.3. LIMITED RIGHT OF REPLACEMENT OR REFUND - If you
discover a defect in this electronic work within 90 days of receiving it, you
can receive a refund of the money (if any) you paid for it by sending a
written explanation to the person you received the work from. If you
received the work on a physical medium, you must return the medium with
your written explanation. The person or entity that provided you with the
defective work may elect to provide a replacement copy in lieu of a refund.
If you received the work electronically, the person or entity providing it to
you may choose to give you a second opportunity to receive the work
electronically in lieu of a refund. If the second copy is also defective, you
may demand a refund in writing without further opportunities to fix the
problem.
effort to identify, do copyright research on, transcribe and proofread works
not protected by U.S. copyright law in creating the Project Gutenberg™
collection. Despite these efforts, Project Gutenberg™ electronic works, and
the medium on which they may be stored, may contain “Defects,” such as,
but not limited to, incomplete, inaccurate or corrupt data, transcription
errors, a copyright or other intellectual property infringement, a defective or
damaged disk or other medium, a computer virus, or computer codes that
damage or cannot be read by your equipment.
1.F.2. LIMITED WARRANTY, DISCLAIMER OF DAMAGES - Except
for the “Right of Replacement or Refund” described in paragraph 1.F.3, the
Project Gutenberg Literary Archive Foundation, the owner of the Project
Gutenberg™ trademark, and any other party distributing a Project
Gutenberg™ electronic work under this agreement, disclaim all liability to
you for damages, costs and expenses, including legal fees. YOU AGREE
THAT YOU HAVE NO REMEDIES FOR NEGLIGENCE, STRICT
LIABILITY, BREACH OF WARRANTY OR BREACH OF CONTRACT
EXCEPT THOSE PROVIDED IN PARAGRAPH 1.F.3. YOU AGREE
THAT THE FOUNDATION, THE TRADEMARK OWNER, AND ANY
DISTRIBUTOR UNDER THIS AGREEMENT WILL NOT BE LIABLE
TO YOU FOR ACTUAL, DIRECT, INDIRECT, CONSEQUENTIAL,
PUNITIVE OR INCIDENTAL DAMAGES EVEN IF YOU GIVE
NOTICE OF THE POSSIBILITY OF SUCH DAMAGE.
1.F.3. LIMITED RIGHT OF REPLACEMENT OR REFUND - If you
discover a defect in this electronic work within 90 days of receiving it, you
can receive a refund of the money (if any) you paid for it by sending a
written explanation to the person you received the work from. If you
received the work on a physical medium, you must return the medium with
your written explanation. The person or entity that provided you with the
defective work may elect to provide a replacement copy in lieu of a refund.
If you received the work electronically, the person or entity providing it to
you may choose to give you a second opportunity to receive the work
electronically in lieu of a refund. If the second copy is also defective, you
may demand a refund in writing without further opportunities to fix the
problem.
Page 106
1.F.4. Except for the limited right of replacement or refund set forth in
paragraph 1.F.3, this work is provided to you ‘AS-IS’, WITH NO OTHER
WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO WARRANTIES OF MERCHANTABILITY OR
FITNESS FOR ANY PURPOSE.
1.F.5. Some states do not allow disclaimers of certain implied warranties or
the exclusion or limitation of certain types of damages. If any disclaimer or
limitation set forth in this agreement violates the law of the state applicable
to this agreement, the agreement shall be interpreted to make the maximum
disclaimer or limitation permitted by the applicable state law. The invalidity
or unenforceability of any provision of this agreement shall not void the
remaining provisions.
1.F.6. INDEMNITY - You agree to indemnify and hold the Foundation, the
trademark owner, any agent or employee of the Foundation, anyone
providing copies of Project Gutenberg™ electronic works in accordance
with this agreement, and any volunteers associated with the production,
promotion and distribution of Project Gutenberg™ electronic works,
harmless from all liability, costs and expenses, including legal fees, that
arise directly or indirectly from any of the following which you do or cause
to occur: (a) distribution of this or any Project Gutenberg work, (b)
alteration, modification, or additions or deletions to any Project Gutenberg
work, and (c) any Defect you cause.
Section 2. Information about the Mission of Project
Gutenberg
Project Gutenberg is synonymous with the free distribution of electronic
works in formats readable by the widest variety of computers including
obsolete, old, middle-aged and new computers. It exists because of the
efforts of hundreds of volunteers and donations from people in all walks of
life.
Volunteers and financial support to provide volunteers with the assistance
they need are critical to reaching Project Gutenberg’s goals and ensuring
that the Project Gutenberg collection will remain freely available for
paragraph 1.F.3, this work is provided to you ‘AS-IS’, WITH NO OTHER
WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO WARRANTIES OF MERCHANTABILITY OR
FITNESS FOR ANY PURPOSE.
1.F.5. Some states do not allow disclaimers of certain implied warranties or
the exclusion or limitation of certain types of damages. If any disclaimer or
limitation set forth in this agreement violates the law of the state applicable
to this agreement, the agreement shall be interpreted to make the maximum
disclaimer or limitation permitted by the applicable state law. The invalidity
or unenforceability of any provision of this agreement shall not void the
remaining provisions.
1.F.6. INDEMNITY - You agree to indemnify and hold the Foundation, the
trademark owner, any agent or employee of the Foundation, anyone
providing copies of Project Gutenberg™ electronic works in accordance
with this agreement, and any volunteers associated with the production,
promotion and distribution of Project Gutenberg™ electronic works,
harmless from all liability, costs and expenses, including legal fees, that
arise directly or indirectly from any of the following which you do or cause
to occur: (a) distribution of this or any Project Gutenberg work, (b)
alteration, modification, or additions or deletions to any Project Gutenberg
work, and (c) any Defect you cause.
Section 2. Information about the Mission of Project
Gutenberg
Project Gutenberg is synonymous with the free distribution of electronic
works in formats readable by the widest variety of computers including
obsolete, old, middle-aged and new computers. It exists because of the
efforts of hundreds of volunteers and donations from people in all walks of
life.
Volunteers and financial support to provide volunteers with the assistance
they need are critical to reaching Project Gutenberg’s goals and ensuring
that the Project Gutenberg collection will remain freely available for
Page 107
generations to come. In 2001, the Project Gutenberg Literary Archive
Foundation was created to provide a secure and permanent future for
Project Gutenberg and future generations. To learn more about the Project
Gutenberg Literary Archive Foundation and how your efforts and donations
can help, see Sections 3 and 4 and the Foundation information page at
www.gutenberg.org.
Section 3. Information about the Project Gutenberg
Literary Archive Foundation
The Project Gutenberg Literary Archive Foundation is a non-profit 501(c)
(3) educational corporation organized under the laws of the state of
Mississippi and granted tax exempt status by the Internal Revenue Service.
The Foundation’s EIN or federal tax identification number is 64-6221541.
Contributions to the Project Gutenberg Literary Archive Foundation are tax
deductible to the full extent permitted by U.S. federal laws and your state’s
laws.
The Foundation’s business office is located at 41 Watchung Plaza #516,
Montclair NJ 07042, USA, +1 (862) 621-9288. Email contact links and up
to date contact information can be found at the Foundation’s website and
official page at www.gutenberg.org/contact
Section 4. Information about Donations to the Project
Gutenberg Literary Archive Foundation
Project Gutenberg™ depends upon and cannot survive without widespread
public support and donations to carry out its mission of increasing the
number of public domain and licensed works that can be freely distributed
in machine-readable form accessible by the widest array of equipment
including outdated equipment. Many small donations ($1 to $5,000) are
particularly important to maintaining tax exempt status with the IRS.
The Foundation is committed to complying with the laws regulating
charities and charitable donations in all 50 states of the United States.
Compliance requirements are not uniform and it takes a considerable effort,
much paperwork and many fees to meet and keep up with these
Foundation was created to provide a secure and permanent future for
Project Gutenberg and future generations. To learn more about the Project
Gutenberg Literary Archive Foundation and how your efforts and donations
can help, see Sections 3 and 4 and the Foundation information page at
www.gutenberg.org.
Section 3. Information about the Project Gutenberg
Literary Archive Foundation
The Project Gutenberg Literary Archive Foundation is a non-profit 501(c)
(3) educational corporation organized under the laws of the state of
Mississippi and granted tax exempt status by the Internal Revenue Service.
The Foundation’s EIN or federal tax identification number is 64-6221541.
Contributions to the Project Gutenberg Literary Archive Foundation are tax
deductible to the full extent permitted by U.S. federal laws and your state’s
laws.
The Foundation’s business office is located at 41 Watchung Plaza #516,
Montclair NJ 07042, USA, +1 (862) 621-9288. Email contact links and up
to date contact information can be found at the Foundation’s website and
official page at www.gutenberg.org/contact
Section 4. Information about Donations to the Project
Gutenberg Literary Archive Foundation
Project Gutenberg™ depends upon and cannot survive without widespread
public support and donations to carry out its mission of increasing the
number of public domain and licensed works that can be freely distributed
in machine-readable form accessible by the widest array of equipment
including outdated equipment. Many small donations ($1 to $5,000) are
particularly important to maintaining tax exempt status with the IRS.
The Foundation is committed to complying with the laws regulating
charities and charitable donations in all 50 states of the United States.
Compliance requirements are not uniform and it takes a considerable effort,
much paperwork and many fees to meet and keep up with these
Page 108
requirements. We do not solicit donations in locations where we have not
received written confirmation of compliance. To SEND DONATIONS or
determine the status of compliance for any particular state visit
www.gutenberg.org/donate.
While we cannot and do not solicit contributions from states where we have
not met the solicitation requirements, we know of no prohibition against
accepting unsolicited donations from donors in such states who approach us
with offers to donate.
International donations are gratefully accepted, but we cannot make any
statements concerning tax treatment of donations received from outside the
United States. U.S. laws alone swamp our small staff.
Please check the Project Gutenberg web pages for current donation methods
and addresses. Donations are accepted in a number of other ways including
checks, online payments and credit card donations. To donate, please visit:
www.gutenberg.org/donate.
Section 5. General Information About Project Gutenberg
electronic works
Professor Michael S. Hart was the originator of the Project Gutenberg
concept of a library of electronic works that could be freely shared with
anyone. For forty years, he produced and distributed Project Gutenberg
eBooks with only a loose network of volunteer support.
Project Gutenberg eBooks are often created from several printed editions,
all of which are confirmed as not protected by copyright in the U.S. unless a
copyright notice is included. Thus, we do not necessarily keep eBooks in
compliance with any particular paper edition.
Most people start at our website which has the main PG search facility:
www.gutenberg.org.
This website includes information about Project Gutenberg, including how
to make donations to the Project Gutenberg Literary Archive Foundation,
received written confirmation of compliance. To SEND DONATIONS or
determine the status of compliance for any particular state visit
www.gutenberg.org/donate.
While we cannot and do not solicit contributions from states where we have
not met the solicitation requirements, we know of no prohibition against
accepting unsolicited donations from donors in such states who approach us
with offers to donate.
International donations are gratefully accepted, but we cannot make any
statements concerning tax treatment of donations received from outside the
United States. U.S. laws alone swamp our small staff.
Please check the Project Gutenberg web pages for current donation methods
and addresses. Donations are accepted in a number of other ways including
checks, online payments and credit card donations. To donate, please visit:
www.gutenberg.org/donate.
Section 5. General Information About Project Gutenberg
electronic works
Professor Michael S. Hart was the originator of the Project Gutenberg
concept of a library of electronic works that could be freely shared with
anyone. For forty years, he produced and distributed Project Gutenberg
eBooks with only a loose network of volunteer support.
Project Gutenberg eBooks are often created from several printed editions,
all of which are confirmed as not protected by copyright in the U.S. unless a
copyright notice is included. Thus, we do not necessarily keep eBooks in
compliance with any particular paper edition.
Most people start at our website which has the main PG search facility:
www.gutenberg.org.
This website includes information about Project Gutenberg, including how
to make donations to the Project Gutenberg Literary Archive Foundation,
Page 109
how to help produce our new eBooks, and how to subscribe to our email
newsletter to hear about new eBooks.
newsletter to hear about new eBooks.
Page 110
back
Page 111
back
Page 112
back
Page 113
back
Page 114
back
Page 115
Page 116
back
Page 117
back