Researches on Cellulose_ 1895-1900 C. F. Cross and E. J. Bevan 896 downloads.pdf

The Project Gutenberg eBook of Researches on Cellulose, 1895-1900
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: Researches on Cellulose, 1895-1900

Author: C. F. Cross
E. J. Bevan

Release date: September 16, 2007 [eBook #22620]

Language: English

Other information and formats: www.gutenberg.org/ebooks/22620

Credits: Produced by Juliet Sutherland, Josephine Paolucci and the
Online Distributed Proofreading Team at http://www.pgdp.net.
(This file was produced from images generously made
available by The Internet Archive/Million Book Project).

*** START OF THE PROJECT GUTENBERG EBOOK RESEARCHES ON
CELLULOSE, 1895-1900 ***

RESEARCHES ON CELLULOSE
1895-1900

BY

CROSS & BEVAN
(C. F. CROSS AND E. J. BEVAN)

SECOND EDITION

LONGMANS, GREEN, AND CO.
39 PATERNOSTER ROW, LONDON
NEW YORK, BOMBAY, AND CALCUTTA

1907

All rights reserved

Transcriber's note: The sections in the Table of Contents are not
used in the actual text. They have been added for clarity. Minor
typos have been corrected and footnotes moved to the end of the
sections

PREFACE TO SECOND EDITION
This edition is a reprint of the first in response to a continuous demand for the
book. The matter, consisting as it does largely of records, does not call for any
revision, and, as a contribution to the development of theory, any particular interest
which it has is associated with the date at which it was written.
The volume which has since appeared is the sequel, and aims at an exposition of
the subject "to date".

PREFACE
This volume, which is intended as a supplement to the work which we published in
1895, gives a brief account of researches which have been subsequently published,
as well as of certain of our own investigations, the results of which are now for the
first time recorded.
We have not attempted to give the subject-matter the form of a connected record.
The contributions to the study of 'Cellulose' which are noticed are spread over a
large area, are mostly 'sectional' in their aim, and the only cohesion which we can
give them is that of classifying them according to the plan of our original work.
Their subject-matter is reproduced in the form of a précis, as much condensed as
possible; of the more important papers the original title is given. In all cases we
have endeavoured to reproduce the Author's main conclusions, and in most cases
without comment or criticism.
Specialists will note that the basis of investigation is still in a great measure
empirical; and of this the most obvious criterion is the confusion attaching to the
use of the very word 'Cellulose.' This is due to various causes, one of which is the
curious specialisation of the term in Germany as the equivalent of 'wood cellulose.'
The restriction of this general or group term has had an influence even in scientific
circles. Another influence preventing the recognition of the obvious and, as we
think, inevitable basis of classification of the 'celluloses' is the empiricism of the
methods of agricultural chemistry, which as regards cellulose are so far chiefly
concerned with its negative characteristics and the analytical determination of the
indigestible residue of fodder plants. Physiologists, again, have their own views and
methods in dealing with cellulose, and have hitherto had but little regard to the
work of the chemist in differentiating and classifying the celluloses on a systematic
basis. There are many sides to the subject, and it is only by a sustained effort
towards centralisation that the general recognition of a systematic basis can be
secured.
We may, we hope usefully, direct attention to the conspicuous neglect of the subject
in this country. To the matter of the present volume, excluding our own
investigations, there are but two contributions from English laboratories. We invite
the younger generation of students of chemistry to measure the probability of
finding a working career in connection with the cellulose industries. They will not
find this invitation in the treatment accorded to the subject in text-books and
lectures. It is probable, indeed, that the impression produced by their studies is that

the industries in coal-tar products largely exceed in importance those of which the
carbohydrates are the basis; whereas the former are quite insignificant by
comparison. A little reflection will prove that cellulose, starch, and sugar are of vast
industrial moment in the order in which they are mentioned. If it is an open
question to what extent science follows industry, or vice versa, it is not open to
doubt that scientific men, and especially chemists, are called in these days to lead
and follow where industrial evolution is most active. There is ample evidence of
activity and great expansion in the cellulose industries, especially in those which
involve the chemistry of the raw material; and the present volume should serve to
show that there is rapid advance in the science of the subject. Hence our appeal to
the workers not to neglect those opportunities which belong to the days of small
beginnings.
We have especially to acknowledge the services of Mr. J. F. Briggs in
investigations which are recorded on pp. 34-40 and pp. 125-133 of the text.

CONTENTS
THE MATTER OF THIS VOLUME MAY BE DIVIDED INTO THE
FOLLOWING SECTIONS

PAGE

INTRODUCTION—DEALING WITH THE SUBJECT IN GENERAL OUTLINE
1

SECTION

I. GENERAL CHEMISTRY OF THE TYPICAL COTTON CELLULOSE 13

II. SYNTHETICAL DERIVATIVES—SULPHOCARBONATES AND ESTERS 27

III. DECOMPOSITIONS OF CELLULOSE SUCH AS THROW LIGHT ON THE
PROBLEM OF ITS CONSTITUTION 67

IV. CELLULOSE GROUP, INCLUDING HEMICELLULOSES AND TISSUE
CONSTITUENTS OF FUNGI 97

V. FURFUROIDS, i.e. PENTOSANES AND FURFURAL-YIELDING
CONSTITUENTS GENERALLY 114

VI. THE LIGNOCELLULOSES 125

VII. PECTIC GROUP 152

VIII. INDUSTRIAL AND TECHNICAL. GENERAL REVIEW 155

INDEX OF AUTHORS 177

INDEX OF SUBJECTS 178

CELLULOSE

INTRODUCTION
In the period 1895-1900, which has elapsed since the original publication of our
work on 'Cellulose,' there have appeared a large number of publications dealing
with special points in the chemistry of cellulose. So large has been the contribution
of matter that it has been considered opportune to pass it under review; and the
present volume, taking the form of a supplement to the original work, is designed to
incorporate this new matter and bring the subject as a whole to the level to which it
is thereby to be raised. Some of our critics in reviewing the original work have
pronounced it 'inchoate.' For this there are some explanations inherent in the matter
itself. It must be remembered that every special province of the science has its
systematic beginning, and in that stage of evolution makes a temporary 'law unto
itself.' In the absence of a dominating theory or generalisation which, when
adopted, gives it an organic connection with the general advance of the science,
there is no other course than to classify the subject-matter. Thus 'the carbohydrates'
may be said to have been in the inchoate condition, qualified by a certain
classification, prior to the pioneering investigations of Fischer. In attacking the
already accumulated and so far classified material from the point of view of a
dominating theory, he found not only that the material fell into systematic order and
grew rapidly under the stimulus of fruitful investigation, but in turn contributed to
the firmer establishment of the theoretical views to which the subject owed its
systematic new birth. On the other hand, every chemist knows that it is only the
simpler of the carbohydrates which are so individualised as to be connoted by a
particular formula in the stereoisomeric system. Leaving the monoses, there is even
a doubt as to the constitution of cane sugar; and the elements of uncertainty thicken
as we approach the question of the chemical structure of starch. This unique
product of plant life has a literature of its own, and how little of this is fully known
to what we may term the 'average chemist' is seen by the methods he will employ
for its quantitative estimation. In one particular review of our work where we are
taken to task for producing 'an aggravating book, inchoate in the highest degree ...
disfigured by an obscurity of diction which must materially diminish its usefulness'
['Nature,' 1897, p. 241], the author, who is a well-known and competent critic,
makes use of the short expression in regard to the more complex carbohydrates,
'Above cane sugar, higher in the series, all is chaos,' and in reference to starch, 'the
subject is still enshrouded in mystery.' This 'material' complexity is at its maximum
with the most complex members of the series, which are the celluloses, and we
think accounts in part for the impatience of our critic. 'Obscurity of diction' is a
personal quantity, and we must leave that criticism to the fates. We find also that

many workers whose publications we notice in this present volume quite ignore the
plan of the work, though they make use of its matter. We think it necessary to
restate this plan, which, we are satisfied, is systematic, and, in fact, inevitable.
Cellulose is in the first instance a structure, and the anatomical relationships supply
a certain basis of classification. Next, it is known to us and is defined by the
negative characteristics of resistance to hydrolytic actions and oxidations. These are
dealt with in the order of their intensity. Next we have the more positive definition
by ultimate products of hydrolysis, so far as they are known, which discloses more
particularly the presence of a greater or less proportion of furfural-yielding groups.
Putting all these together as criteria of function and composition we find they
supply common or general dividing lines, within which groups of these products
are contained. The classification is natural, and in that sense inevitable; and it not
only groups the physiological and chemical facts, but the industrial also. We do not
propose to argue the question whether the latter adds any cogency to a scientific
scheme. We are satisfied that it does, and we do not find any necessity to exclude a
particular set of phenomena from consideration, because they involve 'commercial'
factors. We have dealt with this classification in the original work (p. 78), and we
discuss its essential basis in the present volume (p. 28) in connection with the
definition of a 'normal' cellulose. But the 'normal' cellulose is not the only cellulose,
any more than a primary alcohol or an aliphatic alcohol are the only alcohols. This
point is confused or ignored in several of the recent contributions of investigators.
It will suffice to cite one of these in illustration. On p. 16 we give an account of an
investigation of the several methods of estimating cellulose, which is full of
valuable and interesting matter. The purpose of the author's elaborate comparative
study is to decide which has the strongest claims to be regarded as the 'standard'
method. They appear to have a preference for the method of Lange—viz. that of
heating at high temperatures (180°) with alkaline hydrates, but the investigation
shows that (as we had definitely stated in our original work, p. 214) this is subject
to large and variable errors. The adverse judgment of the authors, we may point out,
is entirely determined on the question of aggregate weight or yield, and without
reference to the ultimate composition or constitution of the final product. None of
the available criteria are applied to the product to determine whether it is a cellulose
(anhydride) or a hydrate or a hydrolysed product. After these alkali-fusion
processes the method of chlorination is experimentally reviewed and dismissed for
the reason that the product retains furfural-yielding groups, which is, from our point
of view, a particular recommendation, i.e. is evidence of the selective action of the
chlorine and subsequent hydrolysis upon the lignone group. As a matter of fact it is
the only method yet available for isolating the cellulose from a lignocellulose by a
treatment which is quantitatively to be accounted for in every detail of the
reactions. It does not yield a 'normal' cellulose, and this is the expression which, in
our opinion, the authors should have used. It should have been pointed out,

moreover, that, as the cellulose is separated from actual condensed combination
with the lignone groups, it may be expected to be obtained in a hydrated form, and
also not as a homogeneous substance like the normal cotton cellulose. The product
is a cellulose of the second group of the classification. Another point in this
investigation which we must criticise is the ultimate selection of the Schulze
method of prolonged maceration with nitric acid and a chlorate, followed by
suitable hydrolysis of the non-cellulose derivatives to soluble products. Apart from
its exceptional inconvenience, rendering it quite impracticable in laboratories which
are concerned with the valuation of cellulosic raw materials for industrial purposes,
the attack of the reagent is complex and ill-defined. This criticism we would make
general by pointing out that such processes quite ignore the specific characteristics
of the non-cellulose components of the compound celluloses. The second division
of the plan of our work was to define these constituents by bringing together all that
had been established concerning them. These groups are widely divergent in
chemical character, as are the compound celluloses in function in the plant.
Consequently there is for each a special method of attack, and it is a reversion to
pure empiricism to expect any one treatment to act equally on the pectocelluloses,
lignocelluloses, and cutocelluloses. Processes of isolating cellulose are really more
strictly defined as methods of selective and regulated attack of the groups with
which they occur, combined or mixed. A chemist familiar with such types as rhea or
ramie (pectocellulose), jute (lignocellulose), and raffia (cutocellulose) knows
exactly the specific treatment to apply to each for isolating the cellulose, and must
view with some surprise the appearance at this date of such 'universal prescriptions'
as the process in question.
The third division of our plan of arrangement comprised the synthetical derivatives
of the celluloses, the sulphocarbonates first, as peculiarly characteristic, and then
the esters, chiefly the acetates, benzoates, and nitrates. To these, investigators
appear to have devoted but little attention, and the contribution of new matter in the
present volume is mainly the result of our own researches. It will appear from this
work that an exhaustive study of the cellulose esters promises to assist very
definitely in the study of constitutional problems.
This brings us to the fourth and, to the theoretical chemist, the most important
aspect of the subject, the problem of the actual molecular structure of the celluloses
and compound celluloses. It is herein we are of opinion that the subject makes a
'law unto itself.' If the constitution of starch is shrouded in mystery and can only be
vaguely expressed by generalising a complex mass of statistics of its successive
hydrolyses, we can only still more vaguely guess at the distance which separates us
from a mental picture of the cellulose unit. We endeavour to show by our later
investigations that this problem merges into that of the actual structure of cellulose
in the mass. It is definitely ascertained that a change in the molecule, or reacting

unit, of a cellulose, proportionately affects the structural properties of the derived
compounds, both sulphocarbonates and esters. This is at least an indication that the
properties of the visible aggregates are directly related to the actual configuration of
the chemical units. But it appears that we are barred from the present discussion of
such a problem in absence of any theory of the solid state generally, but more
particularly of those forms of matter which are grouped together as 'colloids.'
Cellulose is distinguished by its inherent constructive functions, and these functions
take effect in the plastic or colloidal condition of the substance. These properties
are equally conspicuous in the synthetical derivatives of the compound. Without
reference, therefore, to further speculations, and not deterred by any apparent
hopelessness of solving so large a problem, it is clear that we have to exhaust this
field by exact measurements of all the constants which can be reduced to numerical
expression. It is most likely that the issue may conflict with some of our current
views of the molecular state which are largely drawn from a study of the relatively
dissociated forms of matter. But such conflicts are only those of enlargement, and
we anticipate that all chemists look for an enlargement of the molecular horizon
precisely in those regions where the forces of cell-life manifest themselves.
The cellulose group has been further differentiated by later investigations. The
fibrous celluloses of which the typical members receive important industrial
applications, graduate by insensible stages into the hemicelluloses which may be
regarded as a well-established sub-group. In considering their morphological and
functional relationships it is evident that the graduation accords with their structure
and the less permanent functions which they fulfil. They are aggregates of monoses
of the various types, chiefly mannose, galactose, dextrose, &c., so far as they have
been investigated.
Closely connected with this group are the constituents of the tissues of fungi. The
recent researches of Winterstein and Gilson, which are noted in this present
volume, have established definitely that they contain a nitrogenous group in
intimate combination with a carbohydrate complex. This group is closely related to
chitin, yielding glucosamin and acetic acid as products of ultimate hydrolysis.
Special interest attaches to these residues, as they are in a sense intermediate
products between the great groups of the carbohydrates and proteids (E. Fischer,
Ber. 19, 1920), and their further investigation by physiological methods may be
expected to disclose a genetic connection.
The lignocelluloses have been further investigated. Certain new types have been
added, notably a soluble or 'pectic' form isolated from the juice of the white currant
(p. 152), and the pith-like wood of the Æschynomene (p. 135).

Further researches on the typical fibrous lignocellulose have given us a basis for
correcting some of the conclusions recorded in our original work, and a study of the
esters has thrown some light on the constitution of the complex (p. 130).
Of importance also is the identification of the hydroxyfurfurals as constituents of
the lignocelluloses generally, and the proof that the characteristic colour-reactions
with phenols (phloroglucinol) may be ascribed to the presence of these compounds
(p. 116).
The pectocelluloses have not been the subject of systematic chemical investigation,
but the researches of Gilson ('La Cristallisation de la Cellulose et la Composition
Chimique de la Membrane Cellulaire Végétale,' 'La Revue,' 'La Cellule,' i. ix.) are
an important contribution to the natural history of cellulose, especially in relation to
the 'pectic' constituents of the parenchymatous celluloses. Indirectly also the
researches of Tollens on the 'pectins' have contributed to the subject in correcting
some of the views which have had a text-book currency for a long period. These are
dealt with on p. 151. The results establish that the pectins are rather the soluble
hydrated form of cellulosic aggregates in which acid groups may be represented;
but such groups are not to be regarded as essentially characteristic of this class of
compounds.
Furfural-yielding Substances (Furfuroids).—This group of plant products has
been, by later investigations, more definitely and exclusively connected with the
celluloses—i.e. with the more permanent of plant tissues. From the characteristic
property of yielding furfural, which they have in common with the pentoses, they
have been assumed to be the anhydrides of these C5 sugars or pentosanes; but the
direct evidence for this assumption has been shown to be wanting. In regard to their
origin the indirect evidences which have accumulated all point to their formation in
the plant from hexoses. Of special interest, in its bearings on this point, is the direct
transformation of levulose into furfural derivatives, which takes place under the
action of condensing agents. The most characteristic is that produced by the action
of anhydrous hydrobromic acid in presence of ether [Fenton], yielding a
brommethyl furfural
C6H12O6 - 4H2O + HBr = C5H3.O2.CH2Br

with a Br atom in the methyl group. These researches of Fenton's appear to us to
have the most obvious and direct bearings upon the genetic relationships of the
plant furfuroids and not only per se. To give them their full significance we must
recall the later researches of Brown and Morris, which establish that cane sugar is a
primary or direct product of assimilation, and that starch, which had been assumed
to be a species of universal matière première, is probably rather a general reserve

for the elaborating work of the plant. If now the aldose groups tend to pass over
into the starch form, representing a temporary overflow product of the assimilating
energy, it would appear that the ketose or levulose groups are preferentially used up
in the elaboration of the permanent tissue. We must also take into consideration the
researches of Lobry de Bruyn showing the labile functions of the typical CO group
in both aldoses and hexoses, whence we may conclude that in the plant-cell the
transition from dextrose to levulose is a very simple and often occurring process.
We ourselves have contributed a link in this chain of evidence connecting the
furfuroids of the plant with levulose or other keto-hexose. We have shown that the
hydroxyfurfurals are constituents of the lignocelluloses. The proportion present in
the free state is small, and it is not difficult to show that they are products of
breakdown of the lignone groups. If we assume that such groups are derived
ultimately from levulose, we have to account for the detachment of the methyl
group. This, however, is not difficult, and we need only call to mind that the
lignocelluloses are characterised by the presence of methoxy groups and a residue
which is directly and easily hydrolysed to acetic acid. Moreover, the condensation
need not be assumed to be a simple dehydration with attendant rearrangement; it
may very well be accompanied or preceded by fixation of oxygen. Leaving out the
hypothetical discussion of minor variations, there is a marked convergence of the
evidence as to the main facts which establish the general relationships of the
furfuroid group. This group includes both saturated and unsaturated or condensed
compounds. The former are constituents of celluloses, the latter of the lignone
complex of the lignocelluloses.
The actual production of furfural by boiling with condensing acids is a quantitative
measure of only a portion, i.e. certain members of the group. The hydroxyfurfurals,
not being volatile, are not measured in this way. By secondary reactions they may
yield some furfural, but as they are highly reactive compounds, and most readily
condensed, they are for the most part converted into complex 'tarry' products.
Hence we have no means, as yet, of estimating those tissue constituents which yield
hydroxyfurfurals; also we have no measure of the furfurane-rings existing
performed in such a condensed complex as lignone. But, chemists having added in
the last few years a large number of facts and well-defined probabilities, it is clear
that the further investigation of the furfuroid group will take its stand upon a much
more adequate basis than heretofore. On the view of 'furfural-yielding' being co-
extensive with 'pentose or pentosane,' not only were a number of important facts
obscured or misinterpreted, but there was a barrenness of suggestion of genetic
relationships. As the group has been widened very much beyond these limits, it is
clear that if any group term or designation is to be retained that of 'furfuroid' is
'neutral' in character, and equally applicable to saturated substances of such widely
divergent chemical character as pentoses, hexosones, glycuronic acid, and perhaps,

most important of all, levulose itself, all of which are susceptible of condensation to
furfural or furfurane derivatives, as well as to those unsaturated compounds,
constituents of plant tissues which are already furfurane derivatives.
From the chemical point of view such terms are perhaps superfluous. But
physiological relationships have a significance of their own; and there is a
physiological or functional cohesion marking this group which calls for
recognition, at least for the time, and we therefore propose to retain the term
furfuroid.[1]
General Experimental Methods.—In the investigation of the cellulose group it is
clear that methods of ultimate hydrolysis are of first importance. None are so
convenient as those which are based on the action of sulphuric acid, more or less
concentrated (H2SO4.3H2O - H2SO4H2O). Such methods have been frequently
employed in the investigations noted in this volume. We notice a common
deficiency in the interpretation of the results. It appears to be sufficient to isolate
and identify a crystalline monose, without reference to the yield or proportion to the
parent substance, to establish some main point in connection with its constitution.
On the other hand, it is clear that in hydrolysing a given cellulose-complex we
ought to aim at complete, i.e. quantitative, statistics. The hydrolytic transformation
of starch to dextrins and maltose has been followed in this way, and the methods
may serve as a model to which cellulose transformations should be approximated.
In fact, what is very much wanted is a systematic re-examination of the typical
celluloses in which all the constants of the terms between the original and the
ultimate monose groups shall be determined. Such constants are similar to those for
the starch-dextrose series, viz. opticity and cupric reduction. Various methods of
fractionation are similarly available, chiefly the precipitation of the intermediate
'dextrins' by alcohol.
Where the original celluloses are homogeneous we should thus obtain
transformation series, similarly expressed to those of starch. In the case of the
celluloses which are mixtures, or of complex constitution, there are various
methods of either fractionating the original, or of selectively attacking particular
monoses resulting from the transformation. By methods which are approximately
quantitative a mixture of groups, such as we have, for instance, in jute cellulose,
could be followed through the several stages of their resolution into monoses. To
put the matter generally, in these colloidal and complex carbohydrates the ordinary
physical criteria of molecular weight are wanting. Therefore, we cannot determine
the relationship of a given product of decomposition to the parent molecule save by
means of a quantitative mass-proportion. Physical criteria are only of determining
value when associated with such constants as cupric reduction, and these, again,

must be referred to some arbitrary initial weight, such as, for convenience, 100
parts of the original.
Instead of adopting these methods, without which, as a typical case, the mechanism
of starch conversions could not have been followed, we have been content with a
purely qualitative study of the analogous series obtainable from the celluloses under
the action of sulphuric acid. A very important field of investigation lies open,
especially to those who are generally familiar with the methods of studying starch
conversions; and we may hope in this direction for a series of valuable
contributions to the problem of the actual constitution of the celluloses.

FOOTNOTES:
[1] In this we are confirmed by other writers. See Tollens, J. für Landw. 1901, p. 27.

SECTION I. GENERAL CHEMISTRY OF THE
TYPICAL COTTON CELLULOSE
(p. 3)[2] Ash Constituents.—It is frequently asserted that silica has a structural
function sui generis in the plant skeleton, having a relationship to the cellulosic
constituents of the plant, distinct from that of the inorganic ash components with
which it is associated. It should be noted that the matter has been specifically
investigated in two directions. In Berl. Ber. 5, 568 (A. Ladenburg), and again in 11,
822 (W. Lange), appear two papers 'On the Nature of Plant Constituents containing
Silicon,' which contain the results of experimental investigations of equisetum
species—distinguished for their exceptionally high 'ash' with large proportion of
silica—to determine whether there are any grounds for assuming the existence of
silicon-organic compounds in the plant, the analogues of carbon compounds. The
conclusions arrived at are entirely negative. In reference to the second assumption
that the cuticular tissues of cereal straws, of esparto, of the bamboo, owe their
special properties to siliceous components, it has been shown by direct experiment
upon the former that their rigidity and resistance to water are in no way affected by
cultivation in a silica-free medium. In other words, the structural peculiarities of the
gramineæ in these respects are due to the physical characteristics chiefly of the
(lignified) cells of the hypodermal tissue, and to the composition and arrangement
of the cells of the cuticle.
'Swedish' filter papers of modern make are so far freed from inorganic constituents
that the weight of the ash may be neglected in nearly all quantitative experiments
[Fresenius, Ztschr. Anal Chem. 1883, 241]. It represents usually about 1/1000 mgr.
per 1 sq. cm. of area of the paper.
The form of an 'ash' derived from a fibrous structure, is that of the 'organic' original,
more or less, according to its proportion and composition. The proportion of
'natural ash' is seldom large enough, nor are the components of such character as to
give a coherent ash, but if in the case of a fibrous structure it is combined or
intimately mixed with inorganic compounds deposited within the fibres from
solution, the latter may be made to yield a perfect skeleton of the fibre after burning
off the organic matter. It is by such means that the mantles used in the Welsbach
system of incandescent lighting are prepared. A purified cotton fabric—or yarn—is
treated with a concentrated solution of the mixed nitrates of thorium and cerium,
and, after drying, the cellulose is burned away. A perfect and coherent skeleton of
the fabric is obtained, composed of the mixed oxides. Such mantles have fulfilled

the requirements of the industry up to the present time, but later experiments
forecast a notable improvement. It has been found that artificial cellulose fibres can
be spun with solutions containing considerable proportions of soluble compounds
of these oxides. Such fibres, when knitted into mantles and ignited, yield an
inorganic skeleton of the oxides of homogeneous structure and smooth contour. De
Mare in 1894, and Knofler in 1895, patented methods of preparing such cellulose
threads containing the salts of thorium and cerium, by spinning a collodion
containing the latter in solution. When finally ignited, after being brought into the
suitable mantle form, there results a structure which proves vastly more durable
than the original Welsbach mantle. The cause of the superiority is thus set forth by
V. H. Lewes in a recent publication (J. Soc. of Arts, 1900, p. 858): 'The alteration in
physical structure has a most extraordinary effect upon the light-giving life of the
mantle, and also on its strength, as after burning for a few hundred hours the
constant bombardment of the mantle by dust particles drawn up by the rush of air in
the chimney causes the formation of silicates on the surface of the mantle owing to
silica being present in the air, and this seems to affect the Welsbach structure far
more than it does the "Clamond" type, with the result that when burned
continuously the Welsbach mantle falls to so low a pitch of light emissivity after
500 to 600 hours, as to be a mere shadow of its former self, giving not more than
one-third of its original light, whilst the Knofler mantle keeps up its light-emitting
power to a much greater extent, and the Lehner fabric is the most remarkable of all.
Two Lehner mantles which have now been burning continuously in my laboratory
for over 3,000 hours give at this moment a brighter light emissivity than most of the
Welsbachs do in their prime.' ...'The new developments of the Clamond process
form as important a step in the history of incandescent gas lighting as the
discoveries which gave rise to the original mantles.'
It has further been found that the oxides themselves can be dissolved in the
cellulose alkaline sulphocarbonate (viscose) solution, and artificial threads have
been spun containing from 25 to 30 p.ct. of the oxides in homogeneous admixture
with the cellulose. This method has obvious advantages over the collodion method
both in regard to the molecular relationship of the oxides to the cellulose and to
cheapness of production.

UNTERSUCHUNGEN ÜBER VERSCHIEDENE
BESTIMMUNGSMETHODEN DER CELLULOSE.

H. Suringar and B. Tollens (Ztschr. angew. Chem. 1896, No. 23).

INVESTIGATION OF METHODS OF DETERMINING
CELLULOSE.

Introduction.—This is an exhaustive bibliography of the subject, describing also the
various methods of cellulose estimation, noted in historical sequence. First, the
Weende 'crude fibre' method (Henneberg) with modifications of Wattenberg,
Holdefleiss, and others is dealt with. The product of this treatment, viz. 'crude fibre'
is a mixture, containing furfuroids and lignone compounds. Next follows a group of
processes which aim at producing a 'pure cellulose' by eliminating lignone
constituents, for which the merely hydrolytic treatments of the Weende method are
ineffectual. The method of F. Schulze—prolonged digestion with dilute nitric acid,
with addition of chlorate—has been largely employed, though the composition of
the product is more or less divergent from a 'pure cellulose.'
Dilute nitric acid at 60-80° (Cross and Bevan) and a dilute mixture of nitric and
sulphuric acids (Lifschutz) have been employed for isolating cellulose from the
lignocelluloses. Hoffmeister modifies the method of Schulze by substituting
hydrochloric acid for the nitric acid. Treatment with the halogens associated with
alkaline processes of hydrolysis is the basis of the methods of Hugo Muller
(bromine water) and Cross and Bevan (chlorine gas). Lastly, the authors notice the
methods based upon the action of the alkaline hydrates at high temperatures (180°)
in presence of water (Lange), or of glycerin (Gabriel). The process of heating to
210° with glycerin only (Hönig) yields a very impure and ill-defined product.
For comparative investigation of these processes certain celluloses and cellulosic
materials were prepared as follows:
(a) 'Rag' cellulose.—A chemical filter paper, containing only cotton and linen
celluloses, was further purified by boiling with dilute acid and dilute alkali. After
thorough washing it was air-dried.
(b) Wood cellulose.—Pine wood sawdust was treated by digestion for fourteen days
with dilute nitric acid with addition of chlorate (Schulze). The mass was washed
and digested with alkaline lye (1.25 p.ct. KOH), and exhaustively washed, treated
with dilute acetic acid; again washed, and finally air-dried.
This product was found to yield 2.3 p.ct. furfural on distillation with HCl (1.06
sp.gr.).
(c) Purified wood.—Pine wood sawdust was treated in succession with dilute
alkalis and acids, in the cold, and with alcohol and ether until exhausted of products
soluble in these liquids and reagents.

In addition to the above the authors have also employed jute fibre and raw cotton
wool in their investigations.
They note that the yield of cellulose is in many cases sensibly lowered by treating
the material after drying at the temperature of 100°. The material for treatment is
therefore weighed in the air-dry condition, and a similar sample weighed off for
drying at 100° for determination of moisture.
The main results of the experimental investigation are as follows:—
Weende process further attacks the purified celluloses as follows: Wood cellulose
losing in weight 8-9 p.ct.; filter paper, 6-7.5 p.ct., and the latter treated a second
time loses a further 4-5 p.ct. It is clear, therefore, that the process is of purely
empirical value.
Schulze.—This process gave a yield of 47.6 p.ct. cellulose from pine wood. The
celluloses themselves, treated by the process, showed losses of 1-3 p.ct. in weight,
much less therefore than in the preceding case.
Hönig's method of heating with glycerin to 210° was found to yield products very
far removed from 'cellulose.' The process may have a certain value in estimations of
'crude fibre,' but is dismissed from further consideration in relation to cellulose.
Lange.—The purpose of the investigation was to test the validity of the statement
that the celluloses are not attacked by alkaline hydrates at 180°. Experiments with
pine wood yielded a series of percentages for cellulose varying from 36 to 41; the
'purified wood' gave also variable numbers, 44 to 49 per cent. It was found possible
to limit these variations by altering the conditions in the later stages of isolating the
product; but further experiments on the celluloses themselves previously isolated
by other processes showed that they were profoundly and variably attacked by the
'Lange' treatment, wood cellulose losing 50 per cent. of its weight, and filter paper
(cellulose) losing 15 per cent. Further, a specimen of jute yielded 58 per cent. of
cellulose by this method instead of the normal 78 per cent. It was also found that
the celluloses isolated by the process, when subjected to a second treatment,
underwent a further large conversion into soluble derivatives, and in a third
treatment further losses of 5-10 per cent were obtained. The authors attach value,
notwithstanding, to the process which they state to yield an 'approximately pure
cellulose,' and they describe a modified method embodying the improvements in
detail resulting from their investigation.
Gabriel's method of heating with a glycerin solution of alkaline hydrate is a
combination of 'Hönig' and 'Lange.' An extended investigation showed as in the
case of the latter that the celluloses themselves are more or less profoundly attacked

by the treatment—further that the celluloses isolated from lignocelluloses and other
complex raw materials are much 'less pure' than those obtained by the Lange
process. Thus, notably in regard to furfural yielding constituents, the latter yield 1-2
p.ct. furfural, whereas specimens of 'jute cellulose' obtained by the Gabriel process
were found to yield 9 to 13 p.ct. furfural.
Cross and Bevan.—Chlorination process yielded in the hands of the authors results
confirming the figures given in 'Cellulose' for yield of cellulose. Investigation of
the products for yield of furfural, gave 9 p.ct. of this aldehyde showing the presence
of celluloses, other than the normal type.
Conclusions.—The subjoined table gives the mean numerical results for yield of
end-product or 'cellulose' by the various methods. In the case of the 'celluloses' the
results are those of the further action of the several processes on the end-product of
a previous process.

Methods
F. Schulze WeendeLange Gabriel Cross and Bevan
Wood cellulose 98.51 91.52 48.22 55.93 —
Filter paper cellulose99.62 95.63 78.17 79.77 —
Swedish filter paper 96.58 — 84.76 — —
Ordinary filter paper 98.17 93.39 86.58 — —
Cotton ('wool') 98.38 89.98 63.96 67.88 —
Jute — — 57.93 71.64 75.27
{49.27
Purified wood — — — —
{46.56
{40.82
Raw wood 47.60 — — —
{38.87

The final conclusion drawn from the results is that none of the processes fulfil the
requirements of an ideal method. Those which may be carried out in a reasonably
short time are deficient in two directions: (1) they yield a 'cellulose' containing
more or less oxycellulose; (2) the celluloses themselves are attacked under the
conditions of treatment, and the end product or cellulose merely represents a
particular and at the same time variable equilibrium, as between the resistance of
the cellulose and the attack of the reagents employed; this attack being by no means
confined to the non-cellulose constituents. Schulze's method appears to give the
nearest approximation to the 'actual cellulose' of the raw material.

(p. 8) SOLUTIONS OF CELLULOSE—(1) ZINC CHLORIDE.—To prepare a
homogeneous solution of cellulose by means of the neutral chloride, a prolonged
digestion at or about 100° with the concentrated reagent is required. The dissolution
of the cellulose is not a simple phenomenon, but is attended with hydrolysis and a
certain degree of condensation. The latter result is evidenced by the formation of
furfural, the former by the presence of soluble carbohydrates in the solution
obtained by diluting the original solution and filtering from the reprecipitated
cellulose. The authors have observed that in carefully conducted experiments cotton
cellulose may be dissolved in the reagent, and reprecipitated with a loss of only 1
p.ct. in weight. This, however, is a 'net' result, and leaves undetermined the degree
of hydration of the recovered cellulose as of hydrolysis of the original to groups of
lower molecular weights. Bronnert finds that a previous hydration of the cellulose
—e.g. by the process of alkaline mercerisation and removal of the alkali by
washing—enables the zinc chloride to effect its dissolution by digestion in the cold.
(U.S. patent, 646,799/1900. See also p. 59.)
Industrial applications.—(a) Vulcanised fibre is prepared by treating paper with
four times its weight of the concentrated aqueous solution (65-75° B.), and in the
resulting gelatinised condition is worked up into masses, blocks, sheets, &c., of any
required thickness. The washing of these masses to remove the zinc salt is a very
lengthy operation.
To render the product waterproof the process of nitration is sometimes superadded
[D.R.P. 3181/1878]. Further details of manufacture are given in Prakt. Handbuch d.
Papierfabrikation, p. 1703 [C. Hofmann].
(b) Calico-printing.—The use of the solution as a thickener or colour vehicle, more
especially as a substitute for albumen in pigment styles, was patented by E. B.
Manby, but the process has not been industrially developed [E.P. 10,466 / 1894].
(c) Artificial silk.—This is a refinement of the earlier applications of the solution in
spinning cellulose threads for conversion into carbon filaments for electrical glow-
lamps. This section will be found dealt with on p. 59.
(p. 13) (2) Cuprammonium solution.—The application of the solution of cellulose
in cuprammonium to the production of a fine filament in continuous length,
'artificial silk,' has been very considerably studied and developed in the period
1897-1900, as evidenced by the series of patents of Fremery and Urban, Pauly,
Bronnert, and others. The subject will also be found dealt with on p. 58.

(p. 15) Reactions of cellulose with iodine.—In a recent paper, F. Mylius deals with
the reaction of starch and cellulose with iodine, pointing out that the blue
colouration depends upon the presence of water and iodides. In absence of the
latter, and therefore in presence of compounds which destroy or absorb hydriodic
acid—e.g. iodic acid—there results a brown addition product. The products in
question have the characteristics of solid solutions of the halogen. (Berl. Ber. 1895,
390.)
(24) Mercerisation—Notwithstanding the enormous recent developments in the
industrial application of the mercerising reaction, there have been no noteworthy
contributions to the theoretical aspects of the subject. The following abstract gives
an outline of the scope of an important technical work on the subject.

DIE MERCERISATION DER BAUMWOLLE.

Paul Gardner (Berlin: 1898. J. Springer).

THE MERCERISATION OF COTTON.

This monograph of some 150 pages is chiefly devoted to the patent literature of the
subject. The chemical and physical modifications of the cotton substance under the
action of strong alkaline lye, were set forth by Mercer in 1844-5, and there has
resulted from subsequent investigations but little increase in our knowledge of the
fundamental facts. The treatment was industrially developed by Mercer in certain
directions, chiefly (1) for preparing webs of cloth required to stand considerable
strain, and (2) for producing crêpon effects by local or topical action of the alkali.
But the results achieved awakened but a transitory interest, and the matter passed
into oblivion; so much so, indeed, that a German patent [No. 30,966] was granted
in 1884 to the Messrs. Depouilly for crêpon effects due to the differential shrinkage
of fabrics under mercerisation, by processes and treatments long previously
described by Mercer. Such effects have had a considerable vogue in recent years,
but it was not until the discovery of the lustreing effect resulting from the
association of the mercerising actions with the condition of strain or tension of the
yarn or fabric that the industry in 'mercerised' goods was started on the lines which
have led to the present colossal development. The merit of this discovery is now
generally recognised as belonging to Thomas and Prevost of Crefeld,
notwithstanding that priority of patent right belongs to the English technologist, H.
A. Lowe.
The author critically discusses the grounds of the now celebrated patent
controversy, arising out of the conflict of the claims of German patent 85,564/1895

of the former, and English patent 4452/1890 of the latter. The author concludes that
Lowe's specification undoubtedly describes the lustreing effect of mercerising in
much more definite terms than that of Thomas and Prevost. These inventors, on the
other hand, realised the effect industrially, which Lowe certainly failed to do, as
evidenced by his allowing the patent to lapse. As an explanation of his failure, the
author suggests that Lowe did not sufficiently extend his observations to goods
made from Egyptian and other long-stapled cottons, in which class only are the full
effects of the added lustre obtained.
Following these original patents are the specifications of a number of inventions
which, however, are of insignificant moment so far as introducing any essential
variation of the mercerising treatment.
The third section of the work describes in detail the various mechanical devices
which have been patented for carrying out the treatment on yarn and cloth.
The fourth section deals with the fundamental facts underlying the process and
effects summed up in the term 'mercerisation.' These are as follows:—
(a) Although all forms of fibrous celluloses are similarly affected by strong alkaline
solutions, it is only the Egyptian and other long-stapled cottons—i.e. the goods
made from them—which under the treatment acquire the special high lustre which
ranks as 'silky.' Goods made from American cottons acquire a certain 'finish' and
lustre, but the effects are not such as to have an industrial value—i.e. a value
proportional to the cost of treatment.
(b) The lustre is determined by exposing the goods to strong tension, either when
under the action of the alkali, or subsequently, but only when the cellulose is in the
special condition of hydration which is the main chemical effect of the mercerising
treatment.
(c) The degree of tension required is approximately that which opposes the
shrinkage in dimensions, otherwise determined by the action of the alkali. The
following table exhibits the variations of shrinkage of Egyptian when mercerised
without tension, under varying conditions as regards the essential factors of the
treatment—viz. (1) concentration of the alkaline lye, (2) temperature, and (3)
duration of action (the latter being of subordinate moment):—

Concentration
of lye 5°B. 10°B. 15°B 25°B 30°B 35°B
(NaOH)
Duration of 11030110301 10 30 1 10 30 1 10 30 1 10 30
action in

minutes
Temperatures
Percentage shrinkages (Egyptian yarns) as under:—
as under:—
2° 00 0 11 1 12.215.215.819.219.821.522.722.722.724.224.524.7
18° 00 0 00 0 8.0 8.8 11.8 19.820.121.021.222.022.323.523.824.7
30° 00 0 00 0 4.6 4.6 6.0 19.019.519.018.519.519.820.721.021.1
80° 00 0 00 0 3.5 3.5 9.8 13.413.714.215.015.115.515.015.215.4

The more important general indications of the above results are—(1) The
mercerisation action commences with a lye of 10°B., and increases with increased
strength of the lye up to a maximum at 35°B. There is, however, a relatively slight
increase of action with the increase of caustic soda from 30-40°B. (2) For optimum
action the temperature should not exceed 15-20°C. (3) The duration of action is of
proportionately less influence as the concentration of the lye increases. As the
maximum effect is attained the action becomes practically instantaneous, the only
condition affecting it being that of penetration—i.e. actual contact of cellulose and
alkali.
(d) The question as to whether the process of 'mercerisation' involves chemical as
well as physical effects is briefly discussed. The author is of opinion that, as the
degree of lustre obtained varies with the different varieties of cotton, the
differentiation is occasioned by differences in chemical constitution of these
various cottons. The influence of the chemical factors is also emphasised by the
increased dyeing capacity of the mercerised goods, which effect, moreover, is
independent of those conditions of strain or tension under mercerisation which
determine lustre. It is found in effect that with a varied range of dye stuffs a given
shade is produced with from 10 to 30 p.ct. less colouring matter than is required for
the ordinary, i.e. unmercerised, goods.
In reference to the constants of strength and elasticity, Buntrock gives the following
results of observations upon a 405 twofold yarn, five threads of 50 cm. length being
taken for each test(Prometheus, 1897, p. 690): (a) the original yarn broke under a
load of 1440 grms.; (b) after mercerisation without tension the load required was
2420 grms.; (c) after mercerisation under strain, 1950 grms. Mercerisation,
therefore, increases the strength of the yarn from 30 to 66 p.ct., the increase being
lessened proportionately to the strain accompanying mercerisation. Elasticity, as
measured by the extension under the breaking load, remains about the same in
yarns mercerised under strain, but when allowed to shrink under mercerisation
there is an increase of 30-40 p.ct. over the original.

The change of form sustained by the individual fibres has been studied by H. Lange
[Farberzeitung, 1898, 197-198], whose microphotographs of the cotton fibres, both
in length and cross-section, are reproduced. In general terms, the change is from the
flattened riband of the original fibre to a cylindrical tube with much diminished and
rounded central canal. The effect of strain under mercerisation is chiefly seen in the
contour of the surface, which is smooth, and the obliteration at intervals of the
canal. Hence the increased transparency and more complete reflection of the light
from the surface, and the consequent approximation to the optical properties of the
silk fibre.
The work concludes with a section devoted to a description of the various practical
systems of mercerisation of yarns in general practice in Germany, and an account of
the methods adopted in dyeing the mercerised yarns.

RESEARCHES ON MERCERISED COTTON.

A. Fraenkel and P. Friedlaender (Mitt. k.-k. Techn. Gew. Mus., Wien, 1898,
326).

The authors, after investigation, are inclined to attribute the lustre of mercerised
cotton to the absence of the cuticle, which is destroyed and removed in the process,
partly by the chemical action of the alkali, and partly by the stretching at one or
other stage of the process. The authors have investigated the action of alcoholic
solutions of soda also. The lustre effects are not obtained unless the action of water
is associated.
In conclusion, the authors give the following particulars of breaking strains and
elasticity:—

Breaking
Elasticity Elongation in
Treatment Experiments strain
mm.
Grammes
1 360 20
Cotton unmercerised. 2 356 20
3 360 22
1 530 44
Mercerised with Soda
2 570 40
35°B.
3 559 35
Alcoholic soda 10 p.ct. 1 645 24
cold 2 600 27

3 610 33
5 740 33
Alcoholic soda 10 p.ct. hot 2 730 38
3 690 30

FOOTNOTES:
[2] This and other similar references are to the matter of the original volume (1895).

SECTION II. SYNTHETICAL DERIVATIVES—
SULPHOCARBONATES AND ESTERS
(p. 25) Cellulose sulphocarbonate.—Further investigations of the reaction of
formation as well as the various reactions of decomposition of the compound, have
not contributed any essential modification or development of the subject as
originally described in the author's first communications. A large amount of
experimental matter has been accumulated in view of the ultimate contribution of
the results to the general theory of colloidal solutions. But viscose is a complex
product and essentially variable, through its pronounced tendency to progressive
decomposition with reversion of the cellulose to its insoluble and uncombined
condition. The solution for this reason does not lend itself to exact measurement of
its physical constants such as might elucidate in some measure the progressive
molecular aggregation of the cellulose in assuming spontaneously the solid
(hydrate) form. Reserving the discussion of these points, therefore, we confine
ourselves to recording results which further elucidate special points.
Normal and other celluloses.—We may certainly use the sulphocarbonate reaction
as a means of defining a normal cellulose. As already pointed out, cotton cellulose
passes quantitatively through the cycle of treatments involved in solution as
sulphocarbonate and decomposition of the solution with regeneration as
structureless or amorphous cellulose (hydrate).
Analysis of this cellulose shows a fall of carbon percentage from 44.4 to 43.3,
corresponding with a change in composition from C6H10O5 to 4C6H10O5.H2O. The
partial hydrolysis affects the whole molecule, and is limited to this effect, whereas,
in the case of celluloses of other types, there is a fractionation of the mass, a portion
undergoing a further hydrolysis to compounds of lower molecular weight and
permanently soluble. Thus in the case of the wood celluloses the percentage
recovered from solution as viscose is from 93 to 95 p.ct. It is evident that these
celluloses are not homogeneous. A similar conclusion results from the presence of
furfural-yielding compounds with the observation that the hydrolysis to soluble
derivatives mainly affects these derivatives. In the empirical characterisation of a
normal cellulose, therefore, we may include the property of quantitative
regeneration or recovery from its solution as sulphocarbonate.
In the use of the word 'normal' as applied to a 'bleached' cotton, we have further to
show in what respects the sulphocarbonate reaction differentiates the bleached or

purified cotton cellulose from the raw product. The following experiments may be
cited: Specimens of American and Egyptian cottons in the raw state, freed from
mechanical, i.e. non-fibrous, impurities, were treated with a mercerising alkali, and
the alkali-cotton subsequently exposed to carbon disulphide. The product of
reaction was further treated as in the preparation of the ordinary solution; but in
place of the usual solution, structureless and homogeneous, it was observed to
retain a fibrous character, and the fibres, though enormously swollen, were not
broken down by continued vigorous stirring. After large dilution the solutions were
filtered, and the fibres then formed a gelatinous mass on the filters. After
purification, the residue was dried and weighed. The American cotton yielded 90.0
p.ct., and the Egyptian 92.0 p.ct. of its substance in the form of this peculiar
modification. The experiment was repeated, allowing an interval of 24 hours to
elapse between the conversion into alkali-cotton and exposure of this to the carbon
disulphide. The quantitative results were identical.
There are many observations incidental to chemical treatments of cotton fabrics
which tend to show that the bleaching process produces other effects than the mere
removal of mechanical impurities. In the sulphocarbonate reaction the raw cotton,
in fact, behaves exactly as a compound cellulose. Whether the constitutional
difference between raw and bleached cotton, thus emphasised, is due to the group
of components of the raw cotton, which are removed in the bleaching process, or to
internal constitutional changes determined by the bleaching treatments, is a
question which future investigation must decide.
The normal sulphocarbonate (viscose).—In the industrial applications of viscose it
is important to maintain a certain standard of composition as of the essential
physical properties of the solution, notably viscosity. It may be noted first that, with
the above-mentioned exception, the various fibrous celluloses show but slight
differences in regard to all the essential features of the reactions involved. In the
mercerising reaction, or alkali-cellulose stage, it is true the differences are
considerable. With celluloses of the wood and straw classes there is a considerable
conversion into soluble alkali-celluloses. If treated with water these are dissolved,
and on weighing back the cellulose, after thorough washing, treatment with acid,
and finally washing and drying, it will be found to have lost from 15 to 20 p.ct. in
weight. The lower grade of celluloses thus dissolved are only in part precipitated in
acidifying the alkaline solution. On the other hand, after conversion into viscose,
the cellulose when regenerated re-aggregates a large proportion of these lower
grade celluloses, and the final loss is as stated above, from 5 to 7 p.ct. only.
Secondly, it is found that all the conditions obtaining in the alkali-cellulose stage
affect the subsequent viscose reaction and the properties of the final solution. The
most important are obviously the proportion of alkali to cellulose and the length of

time they are in contact before being treated with carbon disulphide. An excess of
alkali beyond the 'normal' proportion—viz. 2NaOH per 1 mol. C6H10O5—has little
influence upon the viscose reaction, but lowers the viscosity of the solution of the
sulphocarbonate prepared from it. But this effect equally follows from addition of
alkali to the viscose itself. The alkali-cellulose changes with age; there is a gradual
alteration of the molecular structure of the cellulose, of which the properties of the
viscose when prepared are the best indication. There is a progressive loss of
viscosity of the solution, and a corresponding deterioration in the structural
properties of the cellulose when regenerated from it—especially marked in the film
form. In regard to viscosity the following observations are typical:—
(a) A viscose of 1.8 p.ct. cellulose prepared from an alkali-cellulose
(cotton) fourteen days old.
(b) Viscose of 1.8 p.ct. cellulose from an alkali-cellulose (cotton) three
days old.
(c) Glycerin diluted with 1/3 vol. water.

a b b c
Diluted with
equal vol.
water
Times of flow of equal volumes from narrow orifice in
112 321 103 170
seconds

Similarly the cellulose in reverting to the solid form from these 'degraded' solutions
presents a proportionate loss of cohesion and aggregating power expressed by the
inferior strength and elasticity of the products. Hence, in the practical applications
of the product where the latter properties are of first importance, it is necessary to
adopt normal standards, such as above indicated, and to carefully regulate all the
conditions of treatment in each of the two main stages of reaction, so that a product
of any desired character may be invariably obtained.
Incidentally to these investigations a number of observations have been made on
the alkali-cellulose (cotton) after prolonged storage in closed vessels. It is well
known that starch undergoes hydrolysis in contact with aqueous alkalis of a similar
character to that determined by acids [Béchamp, Annalen, 100, 365]. The recent
researches of Lobry de Bruyn [Rec. Trav. Chim. 14, 156] upon the action of
alkaline hydrates in aqueous solution on the hexoses have established the important
fact of the resulting mobility of the CO group, and the interchangeable relationships
of typical aldoses and ketoses. It was, therefore, not improbable that profound

hydrolytic changes should occur in the cellulose molecule when kept for prolonged
periods as alkali-cellulose.
We may cite an extreme case. A series of products were examined after 12-18
months' storage. They were found to contain only 3-5 p.ct. 'soluble carbohydrates';
these were precipitated by Fehling's solution but without reduction on boiling. They
were, therefore, of the cellulose type. On acidifying with sulphuric acid and
distilling, traces only of volatile acid were produced. It is clear, therefore, that the
change of molecular weight of the cellulose, the disaggregation of the undoubtedly
large molecule of the original 'normal' cellulose—which effects are immediately
recognised in the viscose reactions of such products—are of such otherwise limited
character that they do not affect the constitution of the unit groups. We should also
conclude that the cellulose type of constitution covers a very wide range of minor
variations of molecular weight or aggregation.
The resistance of the normal cellulose to the action of alkalis under these
hydrolysing conditions should be mentioned in conjunction with the observations
of Lange, and the results of the later investigations of Tollens, on its resistance to
'fusion' with alkaline hydrates at high temperatures (180°). The degree of resistance
has been established only on the empirical basis of weighing the product recovered
from such treatment. The product must be investigated by conversion into typical
cellulose derivatives before we can pronounce upon the constitutional changes
which certainly occur in the process. But for the purpose of this discussion it is
sufficient to emphasise the extraordinary resistance of the normal cellulose to the
action of alkalis, and to another of the more significant points of differentiation
from starch.
Chemical constants of cellulose sulphocarbonate (solution).—In investigations of
the solutions we make use of various analytical methods, which may be briefly
described, noting any results bearing upon special points.
Total alkali.—This constant is determined by titration in the usual way. The
cellulose ratio, C6H10O5: 2NaOH, is within the ordinary error of observation, 2: 1
by weight. A determination of alkali therefore determines the percentage of
cellulose.
Cellulose may be regenerated in various ways—viz. by the action of heat, of acids,
of various oxidising compounds. It is purified for weighing by boiling in neutral
sulphite of soda (2 p.ct. solution) to remove sulphur, and in very dilute acids (0.33
p.ct. HCl) to decompose residues of 'organic' sulphur compounds. It may also be
treated with dilute oxidants. After weighing it may be ignited to determine residual
inorganic compounds.

Sulphur.—It has been proved by Lindemann and Motten [Bull. Acad. R. Belg. (3),
23, 827] that the sulphur of sulphocarbonates (as well as of sulphocyanides) is fully
oxidised (to SO3) by the hypochlorites (solutions at ordinary temperatures). The
method may be adapted as required for any form of the products or by-products of
the viscose reaction to be analysed for total sulphur.
The sulphur present in the form of dithiocarbonates, including the typical cellulose
xanthogenic acid, is approximately isolated and determined as CS2 by adding a zinc
salt in excess, and distilling off the carbon disulphide from a water bath. From
freshly prepared solutions a large proportion of the disulphide originally interacting
with the alkali and cellulose is recovered, the result establishing the general
conformity of the reaction to that typical of the alcohols. On keeping the solutions
there is a progressive interaction of the bisulphide and alkali, with formation of
trithiocarbonates and various sulphides. In decomposing these products by acid
reagents hydrogen sulphide and free sulphur are formed, the estimation of which
presents no special difficulties.
In the spontaneous decomposition of the solution a large proportion of the sulphur
resumes the form of the volatile disulphide. This is approximately measured by the
loss in total sulphur in the following series of determinations, in which a viscose of
8.5 p.ct. strength (cellulose) was dried down as a thin film upon glass plates, and
afterwards analysed:
(a) Proportion of sulphur to cellulose (100 pts.) in original.
(b) After spontaneous drying at ordinary temperature.
(c) After drying at 40°C.
(d) As in (c), followed, by 2 hours' heating at 98°.
(e) As in (c), followed by 5 hours' heating at 98°.

a b c d e
Total sulphur 40.025.031.023.710.4

The dried product in (b) and (c) was entirely resoluble in water; in (d) and (e), on
the other hand, the cellulose was fully regenerated, and obtained as a transparent
film.
Iodine reaction.—Fresh solutions of the sulphocarbonate show a fairly constant
reaction with normal iodine solution. At the first point, where the excess of iodine
visibly persists, there is complete precipitation of the cellulose as the bixanthic
sulphide; and this occurs when the proportion of iodine added reaches 3I2: 4Na2O,
calculated to the total alkali.

Other decompositions.—The most interesting is the interaction which occurs
between the cellulose xanthogenate and salts of ammonia, which is taken advantage
of by C. H. Stearn in his patent process of spinning artificial threads from viscose.
The insoluble product which is formed in excess of the solution of ammonia salt is
free from soda, and contains 9-10 p.ct. total sulphur. The product retains its
solubility in water for a short period. The solution may be regarded as containing
the ammonium cellulose xanthate. This rapidly decomposes with liberation of
ammonia and carbon disulphide, and separation of cellulose (hydrate). As
precipitated by ammonium-chloride solution the gelatinous thread contains 15 p.ct.
of cellulose, with a sp.gr. 1.1. The process of 'fixing'—i.e. decomposing the xanthic
residue—consists in a short exposure to the boiling saline solution. The further
dehydration, with increase of gravity and cellulose content, is not considerable. The
thread in its final air-dry state has a sp.gr. 1.48.

Cellulose Benzoates.—These derivatives have been further studied by the authors.
The conditions for the formation of the monobenzoate [C6H9O4.O.CO.Ph] are very
similar to those required for the sulphocarbonate reaction. The fibrous cellulose
(cotton), treated with a 10 p.ct. solution NaOH, and subsequently with benzoyl
chloride, gives about 50 p.ct. of the theoretical yield of monobenzoate. Converted
by 20 p.ct. solution NaOH into alkali-cellulose, and with molecular proportions as
below, the following yields were obtained:—

Calc. for
Monobenzoate
(a) C6H10O5 : 2.0-2.5 NaOH : C6H5.COCl— 150.8}
164.0
(b) C6H10O5 : 2.0-2.5 NaOH : 1.5 mol. C6H5COCl 159.0}

An examination of (a) showed that some dibenzoate (about 7 p.ct.) had been
formed. The product () was exhaustively treated with cuprammonium solution, to
which it yielded about 20 p.ct. of its weight, which was therefore unattacked
cellulose.
Under conditions as above, but with 2.5 mol. C6H5COCl, a careful comparison was
made of the behaviour of the three varieties of cotton, which were taken in the
unspun condition and previously fully bleached and purified.

Sea Island Egyptian American
Aggregate yield of benzoate 153 148 152

Moisture in air dry state 5.28 5.35 5.15
Proportion of dibenzoate p.ct. 8.30 13.70 9.4
Yield of cellulose by saponification 58.0 54.0 58.3

It appears from these results that the benzoate reaction may proceed to a higher
limit (dibenzoate) in the case of Egyptian cotton. This would necessarily imply a
higher limit of 'mercerisation,' under equal conditions of treatment with the alkaline
hydrate. It must be noted that in the conversion of the fibrous cellulose into these
(still) fibrous monobenzoates, there are certain mechanical conditions imported by
the structural features of the ultimate fibres. For the elimination of the influence of
this factor a large number of quantitative comparisons will be necessary. The above
results are therefore only cited as typical of a method of comparative investigation,
more especially of the still open questions of the cause of the superior effects in
mercerisation of certain cottons (see p. 23). It is quite probable that chemical as
well as structural factors co-operate in further differentiating the cottons.
Further investigation of the influence upon the benzoate reaction, of increase of
concentration of the soda lye, used in the preliminary alkali cellulose reaction, from
20 to 33 p.ct. NaOH, established (1) that there is no corresponding increase in the
benzoylation, and (2) that this ester reaction and the sulphocarbonate reaction are
closely parallel, in that the degree and limit of reaction are predetermined by the
conditions of formation of the alkali cellulose.
Monobenzoate prepared as above described is resistant to all solvents of cellulose
and of the cellulose esters, and is therefore freed from cellulose by treatment with
the former, and from the higher benzoate by treatment with the latter. Several of
these, notably pyridine, phenol and nitrobenzene, cause considerable swelling and
gelatinisation of the fibres, but without solution.
Structureless celluloses of the 'normal' type, and insoluble therefore in alkaline lye,
treated under similar conditions to those described above for the fibrous celluloses,
yield a higher proportion of dibenzoate. The following determinations were made
with the cellulose (hydrate) regenerated from the sulphocarbonate:—

Mol. proportions of reagents Yield Dibenzoate p.ct.
C6H10O5 : 2NaOH : 2BzCl 145 34.7
[Caustic soda at 10 per cent. NaOH]
C6H10O5 : 4NaOH : 2BzCl 162 62.7
[Caustic soda at 20 per cent. NaOH]

Limit of reaction.—The cellulose in this form having shown itself more reactive, it
was taken as the basis for determining the maximum proportion of OH groups
yielding to this later reaction. The systematic investigations of Skraup [Monatsh.
10, 389] have determined that as regards the interacting groups the molecular
proportions 1 OH: 7 NaOH: 5 BzCl, ensure complete or maximum esterification.
The maximum of OH groups in cellulose being 4, the reagents were taken in the
proportion C6H10O5: 4 [7 NaOH: 5 BzCl]. The yield of crude product, after
purifying as far as possible from the excess of benzoic acid, was 240 p.ct.
[calculated for dibenzoate 227 p.ct.]. On further investigating the crude product by
treatment with solvents, it was found to have still retained benzoic acid. There was
also present a proportion of only partially attacked cellulose (monobenzoate). The
soluble benzoate amounted to 90 p.ct. of the product. It may be generally concluded
that the dibenzoate represents the normal maximum but that with the hydrated and
partly hydrolysed cellulose molecule, as obtained by regeneration from the
sulphocarbonate, other OH groups may react, but they are only a fractional
proportion in relation to the unit group C6H10O5. In this respect again there is a
close parallelism between the sulphocarbonate and benzoyl-ester reactions.
The dibenzoate, even when prepared from the fibrous celluloses, is devoid of
structure, and its presence in admixture with the fibrous monobenzoate is at once
recognised as it constitutes a structureless incrustation. Under the microscope its
presence in however minute proportion is readily observed. As stated it is soluble in
certain of the ordinary solvents of the cellulose esters, e.g. chloroform, acetic acid,
nitrobenzene, pyridine, and phenol. It is not soluble in ether or alcohol.
Hygroscopic moisture of benzoates.—The crude monobenzoate retains 5.0-5.5 p.ct.
moisture in the air-dry condition. After removal of the residual cellulose this is
reduced to 3.3 p.ct. under ordinary atmospheric conditions. The purified
dibenzoates retain 1.6 p.ct. under similar conditions.
Analysis of benzoates.—On saponification of these esters with alcoholic sodium
hydrate, anomalous results are obtained. The acid numbers, determined by titration
in the usual way, are 10-20 p.ct. in excess of the theoretical, the difference
increasing with the time of boiling. Similarly the residual cellulose shows a
deficiency of 5-9 p.ct.
It is by no means improbable that in the original ester reaction there is a
constitutional change in the cellulose molecule causing it to break down in part
under the hydrolysing treatment with formation of acid products. This point is
under investigation. Normal results as regards acid numbers, on the other hand, are
obtained by saponification with sodium ethylate in the cold, the product being
digested with the half-saturated solution for 12 hours in a closed flask.

The following results with specimens of mono- and dibenzoate, purified, as far as
possible, may be cited:

Combustion results Saponification results
Calc. C6H5.COOH Calc. CelluloseCalc.
Monobenzoate C 56.60 58.65}
46.0 45.9 58.0 60.8
H 5.06 5.26}
Dibenzoate C 63.10 64.86}
65.5 66.6 34.3 40.3
H 3.40 4.86}

The divergence of the numbers, especially for the dibenzoate, in the case of the
hydrogen, and yield of cellulose on hydrolysis are noteworthy. They confirm the
probability of the occurrence of secondary changes in the ester reactions.
Action of nitrating acid upon the benzoates.—From the benzoates above described,
mixed nitro-nitric esters are obtained by the action of the mixture of nitric and
sulphuric acids. The residual OH groups of the cellulose are esterified and
substitution by an NO2 group takes place in the aromatic residue, giving a mixed
nitric nitrobenzoic ester. The analysis of the products points to the entrance of 1
NO2 group in the benzoyl residue in either case; in the cellulose residue 1 OH
readily reacts. Higher degrees of nitration are attained by the process of solution in
concentrated nitric acid and precipitation by pouring into sulphuric acid. In
describing these mixed esters we shall find it necessary to adopt the C12 unit
formula.
In analysing these products we have employed the Dumas method for total
nitrogen. For the O.NO2 groups we have found the nitrometer and the Schloesing
methods to give concordant results. For the NO2 groups it was thought that
Limpricht's method, based upon reduction with stannous chloride in acid solution
(HCl), would be available. The quantitative results, however, were only
approximate, owing to the difficulty of confining the reduction to the NO2 groups
of the nitrobenzoyl residue. By reduction with ammonium sulphide the O.NO2
groups were entirely removed as in the case of the cellulose nitrates; the NO2 was
reduced to NH2 and there resulted a cellulose amidobenzoate, which was diazotised
and combined with amines and phenols to form yellow and red colouring matters,
the reacting residue remaining more or less firmly combined with the cellulose.
Cellulose dinitrate-dinitrobenzoate, and cellulose trinitrate-dinitrobenzoate.—On
treating the fibrous benzoate—which is a dibenzoate on the C12 basis—with the
acid mixture under the usual conditions, a yellowish product is obtained, with a

yield of 140-142 p.ct. The nitrobenzoate is insoluble in ether alcohol, but is soluble
in acetone, acetic acid, and nitrobenzene. In purifying the product the former
solvent is used to remove any cellulose nitrates. To obtain the maximum
combination with nitroxy-groups, the product was dissolved in concentrated nitric
acid, and the solution poured into sulphuric acid.
The following analytical results were obtained (a) for the product obtained directly
from the fibrous benzoate and purified as indicated, (b) for the product from the
further treatment of (a) as described:

Found Calc. for
(a) (b) Dinitrate dinitrobenzoate Trinitrate dinitrobenzoate
Total Nitrogen 7.848.97 7.99 9.24
O.NO2 " 5.005.45 4.00 5.54
NO2 " (Aromatic) 2.843.52 3.99 3.70

With the two benzoyl groups converted into nitro-benzoyl in each product, the limit
of the ester reaction with the cellulose residue is reached at the third OH group.
The nitrogen in the amidobenzoate resulting from the reduction with ammonium
sulphide was 4.5 p.ct.—as against 5.0 p.ct. calculated. The moisture retained by the
fibrous nitrate—nitrobenzoate—in the air-dry state was found to be 1.97 p.ct.
The product from the structureless dibenzoate or tetrabenzoate on the C12 formula,
was prepared and analysed with the following results:

Calc. for Mononitrate
tetranitrobenzoate
Total Nitrogen 6.76 7.25
O.NO2 " 1.30 1.45
NO2 " (Aromatic) 5.46 5.80

The results were confirmed by the yield of product, viz. 131 p.ct. as against the
calculated 136 p.ct. They afford further evidence of the generally low limit of
esterification of the cellulose molecule. From the formation of a 'normal' tetracetate
—i.e. octacetate of the C12 unit—we conclude that 4/5 of the oxygen atoms are
hydroxyl oxygen. Of the 8 OH groups five only react in the mixed esters described
above, and six only in the case of the simple nitric esters. The ester reactions are
probably not simple, but accompanied by secondary reactions within the cellulose
molecule.

(p. 34) Cellulose Acetates.—In the first edition (p. 35) we have committed
ourselves to the statement that 'on boiling cotton with acetic anhydride and sodium
acetate no reaction occurs.' This is erroneous. The error arises, however, from the
somewhat vague statements of Schutzenberger's researches which are current in the
text-books [e.g. Beilstein, 1 ed. p. 586] together with the statement that reaction
only occurs at elevated temperatures (180°). As a matter of fact, reaction takes
place at the boiling temperature of the anhydride. We have obtained the following
results with bleached cotton:

Yield Calc. for Monoacetate
C6H7O4O.C2H3O
Ester reaction 121 p.ct. 125 p.ct.
Saponification{Cellulose 79.9 79.9
{Acetic acid 29.9 29.4

This product is formed without apparent structural alteration of the fibre. It is
entirely insoluble in all the ordinary solvents of the higher acetates. Moreover, it
entirely resists the actions of the special solvents of cellulose—e.g. zinc chloride
and cuprammonium. The compound is in other respects equally stable and inert.
The hygroscopic moisture under ordinary atmospheric conditions is 3.2 p.ct.
Tetracetate.—This product is now made on the manufacturing scale: it has yet to
establish its industrial value.

NITRIRUNG VON KOHLENHYDRATEN.

W. Will und P. Lenze (Berl. Ber., 1898, 68).

NITRATES OF CARBOHYDRATES.

(p. 38) The authors have studied the nitric esters of a typical series of the now well-
defined carbohydrates—pentoses, hexoses, both aldoses and ketoses—bioses and
trioses, the nitrates being prepared under conditions designed to produce the highest
degree of esterification. Starch, wood, gum, and cellulose were also included in the
investigations. The products were analysed and their physical properties
determined. They were more especially investigated in regard to temperatures of
decomposition, which were found to lie considerably lower than that of the
cellulose nitrates. They also show marked and variable instability at 50° C. A main

purpose of the inquiry was to throw light upon a probable cause of the instability of
the cellulose nitrates, viz. the presence of nitrates of hydrolysed products or
carbohydrates of lower molecular weight.
The most important results are these:
Monoses.—The aldoses are fully esterified, in the pentoses 4 OH, in the hexoses 5
OH groups reacting. The pentose nitrates are comparatively stable at 50°; the
hexose nitrates on the other hand are extremely unstable, showing a loss of weight
of 30-40 p.ct. when kept 24 hours at this temperature.
Xylose is differentiated by tending to pass into an anhydride form (C5H10O5-H2O)
under this esterification. When treated in fact with the mixed acids, instead of by
the process usually adopted by the authors of solution in nitric acid and subsequent
addition of the sulphuric acid, it is converted into the dinitrate C5H6O2.(NO3)2.

Ketoses (C6).—These are sharply differentiated from the corresponding aldoses by
giving trinitrates C6H7O2(NO3)3 instead of pentanitrates, the remaining OH groups
probably undergoing internal condensation. The products are, moreover, extremely
stable. It is also noteworthy that levulose gave this same product, the trinitrate of
the anhydride (levulosan) by both methods of nitration (supra).
The bisaccharides or bioses all give the octonitrates. The degree of instability is
variable. Cane-sugar gives a very unstable nitrate. The lactose nitrate is more
stable. Thus at 50° it loses only 0.7 p.ct. in weight in eight days; at 75° it loses 1
p.ct. in twenty-four hours, but with a rapid increase to 23 p.ct. in fifty-four hours.
The maltose octonitrate melts (with decomposition) at a relatively high
temperature, 163°-164°. At 50°-75° it behaves much like the lactose nitrate.
Trisaccharide.—Raffinose yielded the product
C18H21O5.(NO3)11.

Starch yields the hexanitrate (C12) by both methods of nitration. The product has a
high melting and decomposing point, viz. 184°, and when thoroughly purified is
quite stable. It is noted that a yield of 157 p.ct. of this nitrate was obtained, and
under identical conditions cellulose yielded 170 p.ct.
Wood gum, from beech wood, gave a tetranitrate (C10 formula) insoluble in all the
usual solvents for this group of esters.
The authors point out in conclusion that the conditions of instability and
decomposition of the nitrates of the monose-triose series are exactly those noted

with the cellulose nitrates as directly prepared and freed from residues of the
nitrating acids. They also lay stress upon the superior stability of the nitrates of the
anhydrides, especially of the ketoses.

NITRATED CARBOHYDRATES AS FOOD MATERIAL FOR
MOULDS.

Thomas Bokorny (Chem. Zeit., 1896, 20, 985-986).

(p. 38) Cellulose trinitrate (nitrocellulose) will serve as a food supply for moulds
when suspended in distilled water containing the requisite mineral matter and
placed in the dark. The growth is rapid, and a considerable quantity of the vegetable
growth accumulates round the masses of cellulose nitrate, but no growth is
observed if mineral matter is absent. Cellulose itself cannot act as a food supply,
and it seems probable that if glycerol is present cellulose nitrate is no longer made
use of.

NITRATION OF CELLULOSE, HYDROCELLULOSE, AND
OXYCELLULOSE.

Leo Vignon (Compt. rend., 1898, 126, 1658-1661).

(p. 38) Repeated treatment of cellulose, hydrocellulose, and oxycellulose with a
mixture of sulphuric and nitric acids in large excess, together with successive
analyses of the compounds produced, showed that the final product of the reaction
corresponded, in each case, with the fixation of 11 NO groups by a molecule
containing 24 atoms of carbon. On exposure to air, nitrohydrocellulose becomes
yellow and decomposes; nitro-oxycellulose is rather more stable, whilst
nitrocellulose is unaffected. The behaviour of these nitro-derivatives with Schiff's
reagent, Fehling's solution, and potash show that all three possess aldehydic
characters, which are most marked in the case of nitro-oxycellulose. The latter also,
when distilled with hydrochloric acid, yields a larger proportion of furfuraldehyde
than is obtained from nitrocellulose and nitrohydrocellulose.

CELLULOSE NITRATES-EXPLOSIVES.

(p. 38) The uses of the cellulose nitrates as a basis for explosives are limited by
their fibrous character. The conversion of these products into the structureless
homogeneous solid or semi-solid form has the effect of controlling their
combustion. The use of nitroglycerin as an agent for this purpose gives the curious
result of the admixture of two high or blasting explosives to produce a new
explosive capable of extended use for military purposes. The leading
representatives of this class of propulsive explosives, or 'smokeless powders' are
ballistite and cordite, the technology of which will be found fully discussed in
special manuals of the subject. Since the contribution of these inventions to the
development of cellulose chemistry does not go beyond the broad, general facts
above mentioned, we must refer the reader for technical details to the manuals in
question.
There are, however, other means of arriving at structureless cellulose nitrates. One
of these has been recently disclosed, and as the results involve chemical and
technical points of novelty, which are dealt with in a scientific communication, we
reproduce the paper in question, viz.:—

A RE-INVESTIGATION OF THE CELLULOSE NITRATES.

A. Luck and C. F. Cross (J. Soc. Chem. Ind., 1900).

The starting-point of these investigations was a study of the nitrates obtained from
the structureless cellulose obtained from the sulphocarbonate (viscose). This
cellulose in the form of a fine meal was treated under identical conditions with a
sample of pure cotton cellulose, viz. digested for 24 hours in an acid mixture
containing in 100 parts HNO3—24 : H2SO4—70: H2O—6: the proportion of acid to
cellulose being 60 : 1—. After careful purification the products were analysed with
the following results:

Nitrogen Soluble in Ether alcohol
Fibrous nitrate 13.31 4.3 p.ct.
Structureless nitrate 13.35 5.6 "

Examined by the 'heat test' (at 80°) and the 'stability test' (at 135°) they exhibited
the usual instability, and in equal degrees. Nor were the tests affected by exhaustive
treatment with ether, benzene, and alcohol. From this it appears that the process of
solution as sulphocarbonate and regeneration of the cellulose, though it eliminates
certain constituents of an ordinary bleached cellulose, which might be expected to
cause instability, has really no effect in this direction. It also appears that instability

may be due to by-products of the esterification process derived from the cellulose
itself.
The investigation was then extended to liquids having a direct solvent action on
these higher nitrates, more especially acetone. It was necessary, however, to avoid
this solvent action proper, and having observed that dilution with water in
increasing proportions produced a graduated succession of physical changes in the
fibrous ester, we carried out a series of treatments with such diluted acetones.
Quantities of the sample (A), purified as described, but still unstable, were treated
each with five successive changes of the particular liquid, afterwards carefully
freed from the acetone and dried at 40°C. The products, which were found to be
more or less disintegrated, were then tested by the ordinary heat test, stability test,
and explosion test, with the results shown in the table on next page.
In this series of trials the sample 'A' was used in the condition of pulp, viz. as
reduced by the process of wet-beating in a Hollander. A similar series was carried
out with the guncotton in the condition in which it was directly obtained from the
ester reaction. The results were similar to above, fully confirming the progressive
character of the stabilisation with increasing proportions of acetone. These results
prove that washing with the diluted acetone not only rendered the nitrate perfectly
stable, but that the product was more stable than that obtained by the ordinary
process of purification, viz. long-continued boiling and washing in water. We shall
revert to this point after briefly dealing with the associated phenomenon of
structural disintegration. This begins to be well marked when the proportion of
acetone exceeds 80 p.ct. The optimum effect is obtained with mixtures of 90 to 93
acetone and 10 to 7 water (by volume). In a slightly diluted acetone of such
composition, the guncotton is instantly attacked, the action being quite different
from the gelatinisation which precedes solution in the undiluted solvent. The
fibrous character disappears, and the product assumes the form of a free, bulky, still
opaque mass, which rapidly sinks to the bottom of the containing vessel. The
disintegration of the bulk of the nitrate is associated with

Proportions by volume
-- Temperature of Heat Test Heat Test
Acetone Water
Explosion 80° 134°
From 'A' Deg. Mins. Mins.
sample. 20 80 137 3 4
30 70 160 3 4
40 60 180 7 18
No fumes
after

50 50 187.5 55 100
60 40 187 45 100
70 30 185 45 100
80 20 -- 50 100
92 8 185 50 100
Structureless powder.
" 'B'
50 50 183 35 100
sample
" 'C' Ordinary service
185 10 41
sample guncotton

a certain solvent action, and on adding an equal bulk of water, the dissolved nitrate
for the most part is precipitated, at the same time that the undissolved but
disintegrated and swollen product undergoes further changes in the direction of
increase of hardness and density. The product being now collected on a filter, freed
from acetone by washing with water and dried, is a hard and dense powder the
fineness of which varies according to the attendant conditions of treatment. With
the main product in certain cases there is found associated a small proportion of
nitrate retaining a fibrous character, which may be separated by means of a fine
sieve. On examining such a residue, we found it to contain only 5.6 p.ct. N, and as
it was insoluble in strong acetone, it may be regarded as a low nitrate or a mixture
of such with unaltered cellulose. Confirming this we found that the product passing
through the sieve showed an increase of nitrogen to 13.43 p.ct. from the 13.31 p.ct.
in the original. Tested by the heat test (50 minutes) and stability test (no fumes after
100 minutes), we found the products to have the characteristics previously noticed.
It is clear, therefore, that this specifically regulated action of acetone produces the
effects (a) of disintegration, and (b) stabilisation. It remains to determine whether
the latter effect was due, as might be supposed, to the actual elimination of a
compound or group of compounds present in the original nitrate, and to be regarded
as the effective cause of instability. It is to be noted first that as a result of the
treatment with the diluted acetone and further dilution after the specific action is
completed, collecting the disintegrated product on a filter and washing with water,
the loss of weight sustained amounts to 3 to 4 p.ct. This loss is due, therefore, to
products remaining dissolved in the filtrate—that is to say, in the much diluted
acetone. These filtrates are in fact opalescent from the presence of a portion of
nitrate in a colloidal (hydrated) form. On distilling off the acetone, a precipitation is
determined. The precipitates are nitrates of variable composition, analysis showing
from 9 to 12 p.ct. of nitric nitrogen. The filtrate from these precipitates containing
only fractional residues of acetone still shows opalescence. On long-continued
boiling a further precipitation is determined, the filtrates from which are clear. It

was in this final clear filtrate that the product assumed to cause the instability of the
original nitrate would be present. The quantity, however, is relatively so small that
we have only been able to obtain and examine it as residue from evaporation to
dryness. An exhaustive qualitative examination established a number of negative
characteristics, with the conclusion that the products were not direct derivatives of
carbohydrates nor aromatic compounds. On the other hand the following positive
points resulted. Although the original diluted acetone extract was neutral to test
papers, yet the residue was acid in character. It contained combined nitric groups,
fused below 200° giving off acid vapours, and afterwards burning with a smoky
flame. On adding lead acetate to the original clear solution, a well-marked
precipitation was determined. The lead compounds thus isolated are characteristic.
They have been obtained in various ways and analysed. The composition varies
with the character of the solution in which the lead compound is formed. Thus in
the opalescent or milky solutions in which a proportion of cellulose nitrate is held
in solution or semi-solution by the acetone still present, the lead acetate causes a
dense coagulation. The precipitates dried and analysed showed 16-20 p.ct. PbO and
11-9 p.ct. N. It is clear that the cellulose nitrates are associated in these precipitates
with the lead salts of the acid compounds in question. When the latter are obtained
from clear solutions, i.e. in absence of cellulose nitrates, they contain 60-63 p.ct.
PbO and 3.5 p.ct. N (obtained as NO).
In further confirmation of the conclusion from these results, viz. that the
nitrocelluloses with no tendency to combine with PbO are associated with acid
products or by-products of the ester reaction combining with the oxide, the lead
reagent was allowed to react in the presence of 90 p.ct. acetone. Water was added,
the disintegrated mass collected, washed with dilute acetic acid, and finally with
water. Various estimations of the PbO fixed in this way have given numbers
varying from 2 to 2.5 p.ct. Such products are perfectly stable. This particular effect
of stabilisation appears, therefore, to depend upon the combination of certain acid
products present in ordinary nitrocelluloses with metallic oxides. In order to further
verify this conclusion, standard specimens of cellulose nitrates have been treated
with a large number of metallic salts under varying conditions of action. It has been
finally established (1) that the effects in question are more particularly determined
by treatment with salts of lead and zinc, and (2) that the simplest method of
treatment is that of boiling the cellulose nitrates with dilute aqueous solutions of
salts of these metals, preferably the acetates. The following results may be cited,
obtained by boiling a purified 'service' guncotton (sample C) with a 1 p.ct. solution
of lead acetate and of zinc acetate respectively. After boiling 60 minutes the nitrates
were washed free from the soluble metallic salts, dried and tested.

Heat Test at 80° Heat Test at 134°

Original sample C 10 41
Treated with lead acetate 67 45
" zinc " 91 45

In conclusion we may briefly resume the main points arrived at in these
investigations.
Causes of instability of cellulose nitrates.—The results of our experiments so far as
to the causes of instability in cellulose nitrates may be summed up as follows:—
(1) Traces of free nitrating acids, which can only occur in the finished products
through careless manufacture, will undoubtedly cause instability, indicated strongly
by the ordinary heat test at 80°, and to a less extent by the heat test at 134°.
(2) Other compounds exist in more intimate association with the cellulose nitrates
causing instability which cannot be removed by exhaustive washing with either hot
or cold water, by digestion in cold dilute alkaline solutions such as sodium
carbonate, or by extracting with ether, alcohol, benzene, &c.; these compounds,
however, are soluble in the solvents of highly nitrated cellulose such as acetone,
acetic ether, pyridine, &c., even when these liquids are so diluted with water or
other non-solvent liquids to such an extent that they have little or no solvent action
upon the cellulose nitrate itself. These solutions containing the bodies causing
instability are neutral to test paper, but become acid upon evaporation by heating.
(This probably explains the presence of free acid when guncotton is purified by
long-continued boiling in water without any neutralising agent being present.)
(3) The bodies causing instability are products or by-products of the original ester
reaction, acid bodies containing nitroxy-groups, but otherwise of ill-defined
characteristics. They combine with the oxides of zinc or lead, giving insoluble
compounds. They are precipitated from their solutions in diluted acetone upon the
addition of soluble salts of these metals.
(4) Cellulose nitrates are rendered stable either by eliminating these compounds, or
by combining them with the oxides of lead or zinc whilst still in association with
cellulose nitrates.
(5) Even the most perfectly purified nitrocellulose will slowly decompose with
formation of unstable acid products by boiling for a long time in water. This effect
is much more apparent at higher temperatures.
Dense structureless or non-fibrous cellulose nitrates can be industrially prepared
(1) by nitrating the amorphous forms of cellulose obtained from its solution as
sulphocarbonate (viscose). The cellulose in this condition reacts with the closest

similarity to the original fibrous cellulose; the products are similar in composition
and properties, including that of instability.
(2) By treating the fibrous cellulose nitrates with liquid solvents of the high nitrate
diluted with non-solvent liquids, and more especially water. The optimum effect is
a specific disintegration or breaking down of their fibrous structure quite distinct
from the gelatinisation which precedes solution in the undiluted solvent, and
occurring within narrow limits of variation in the proportion of the diluting and
non-solvent liquid—for industrial work the most convenient solution to employ is
acetone diluted with about 10 p.ct. of water by volume.
The industrial applications of these results are the basis of English patents 5286
(1898), 18,868 (1898), 18,233 (1898), Luck and Cross (this Journal, 1899, 400,
787).
The structureless guncotton prepared as above described is of quite exceptional
character, and entirely distinct from the ordinary fibrous nitrate or the nitrate
prepared by precipitation from actual solution in an undiluted solvent.[3] By the
process described, the nitrate is obtained at a low cost in the form of a very fine,
dense, structureless, white powder of great purity and stability, entirely free from all
mechanical impurities. The elimination of these mechanical impurities, and also to
a very great extent of coloured compounds contained in the fibrous nitrate, makes
the product also useful in the manufacture of celluloids, artificial silk, &c., whilst
its very dense form gives it a great advantage over ordinary fibrous guncotton for
use in shells and torpedoes, and for the manufacture of gelatinised gunpowders, &c.
It can be compressed with ease into hard masses; and experiments are in progress
with a view of producing from it, in admixture with 'retaining' ingredients, a
military explosive manufactured by means of ordinary black gunpowder machinery
and processes.
Manufacture of sporting powder.—The fact that the fibrous structure of ordinary
guncotton or other cellulose nitrate can be completely or partially destroyed by
treatment with diluted acetone and without attendant solution, constitutes a process
of value for the manufacture of sporting powder having a base of cellulose nitrate
of any degree of nitration. The following is a description of the hardening process.
'Soft grains' are manufactured from ordinary guncotton or other cellulose nitrate
either wholly or in combination with other ingredients, the process employed being
the usual one of revolving in a drum in the damp state and sifting out the grains of
suitable size after drying. These grains are then treated with diluted acetone, the
degree of dilution being fixed according to the hardness and bulk of the finished
grain it is desired to produce (J. Soc. Chem. Ind., 1899, 787). Owing to the wide

limits of dilution and corresponding effect, the process allows of the production of
either a 'bulk' or a 'condensed' powder.
We prefer to use about five litres of the liquid to each one kilo. of grain operated
upon, as this quantity allows of the grains being freely suspended in the liquid upon
stirring. The grains are run into the liquid, which is then preferably heated to the
boiling-point for a few minutes whilst the whole is gently stirred. Under this
treatment the grains assume a more or less rounded gelatinous condition according
to the strength of the liquid. There is, however, no solution of the guncotton and
practically no tendency of the grains to cohere. Each grain, however, is acted upon
throughout and perfectly equally. After a few minutes' treatment, water is gradually
added, when the grains rapidly harden. They are then freed from acetone and
certain impurities by washing with water, heating, and drying. The process is of
course carried out in a vessel provided with any means for gentle stirring and
heating, and with an outlet for carrying off the volatilised solvent which is entirely
recovered by condensation, the grains parting with the acetone with ease.
Stabilising cellulose nitrates.—The process is of especial value in rendering stable
and inert the traces of unstable compounds which always remain in cellulose nitrate
after the ordinary boiling and washing process. It is of greatest value in the
manufacture of collodion cotton used for the preparation of gelatinous blasting
explosives and all explosives composed of nitroglycerin and cellulose nitrates. Such
mixtures seem peculiarly liable to decomposition if the cellulose nitrate is not of
exceptional stability (J. Soc. Chem. Ind., 1899, 787).

EMPLOI DE LA CELLULOSE POUR LA FABRICATION DE FILS
BRILLANTS IMITANT LA SOIE.

E. Bronnert (1) (Rev. Mat. Col., 1900, September, 267).

V. USE OF CELLULOSE IN THE MANUFACTURE OF
IMITATIONS OF SILK (LUSTRA-CELLULOSE).

(p. 45) Introduction.—The problem of spinning a continuous thread of cellulose has
received in later years several solutions. Mechanically all resolve themselves into
the preparation of a structureless filtered solution of cellulose or a cellulose
derivative, and forcing through capillary orifices into some medium which either
absorbs or decomposes the solvent. The author notes here that the fineness and to a
great extent the softness of the product depends upon the dimensions of the
capillary orifice and concentration of the solution. The technical idea involved in
the spinning of artificial fibres is an old one. Réaumur (2) forecast its possibility,

Audemars of Lausanne took a patent as early as 1855 (3) for transforming
nitrocellulose into fine filaments which he called 'artificial silk.' The idea took
practical shape only when it came to be used in connection with filaments for
incandescent lamps. In this connection we may mention the names of the patentees:
—Swinburne (4), Crookes, Weston (5), Swan (6), and Wynne and Powell (7). These
inventors prepared the way for Chardonnet's work, which has been followed since
1888 with continually increasing success.
At this date the lustra-celluloses known may be divided into four classes.
1. 'Artificial silks' obtained from the nitrocelluloses.
2. 'Lustra-cellulose' made from the solution of cellulose in cuprammonium.
3. 'Lustra-cellulose' prepared from the solution of cellulose in chloride of zinc.
4. 'Viscose silks,' by the decomposition of sulphocarbonate of cellulose (Cross and
Bevan).
Group 1. The early history of the Chardonnet process is discussed and some
incidental causes of the earlier failures are dealt with. The process having been
described in detail in so many publications the reader is referred to these for details.
[See Bibliography, (1) and (2), (3) and (4).] The denitrating treatment was
introduced in the period 1888-90 and of course altogether changed the prospects of
the industry; not only does it remove the high inflammability, but adds considerably
to softness, lustre, and general textile quality. In Table I will be found some
important constants for the nitrocellulose fibre; also the fibre after denitration and
the comparative constants for natural silk.

Table 1.

Tenacity Elasticity
(%
(grammes)
elongation)
Nitrocellulose according to Chardonnet German Patent
150 23
No. 81,599
The same after denitration 110 8
Denitrated fibre moistened with water 25 —
Nitrocellulose: Bronnert's German Patent No. 93,009 125 28
The same after denitration (dry) 115 13
The same after denitration (wetted) 32 —

Natural silk 300 18

1. Tenacity is the weight in grammes required to break the thread.
2. Elasticity is the elongation per cent. at breaking.
The numbers are taken for thread of 100 deniers (450 metres of 0.05
grammes = 1 denier). It must be noted that according to the
concentration of the solution and variations in the process of
denitration the constants for the yarn are subject to very considerable
variation.
In regard to the manufacture a number of very serious difficulties have been
surmounted. First, instead of drying the nitrated cellulose, which often led to fires,
&c., it was found better to take it moist from the centrifugal machine, in which
condition it is dissolved (5). It was next found that with the concentrated collodion
the thread could be spun direct into the air, and the use of water as a precipitant was
thus avoided.
With regard to denitration which is both a delicate and disagreeable operation: none
of the agents recommended to substitute the sulphydrates have proved available. Of
these the author mentions ferrous chloride (6), ferrous chloride in alcohol (7),
formaldehyde (8), sulphocarbonates. The different sulphydrates (9) have very
different effects. The calcium compound tends to harden and weaken the thread.
The ammonia compound requires great care and is costly. The magnesium
compound works rapidly and gives the strongest thread. Investigations have
established the following point. In practice it is not necessary to combine the
saponification of cellulose ester with complete reduction of the nitric acid split off.
The latter requires eight molecules of hydrogen sulphide per one molecule
tetranitrocellulose, but with precautions four molecules suffice. It is well known
that the denitration is nearly complete, traces only of nitric groups surviving. Their
reactions with diphenylamine allow a certain identification of artificial silks of this
class. Various other inventors, e.g. Du Vivier (10), Cadoret (11), Lehner (12), have
attempted the addition of other substances to modify the thread. These have all
failed. Lehner, who persisted in his investigations, and with success, only attained
this success, however, by leaving out all such extraneous matters. Lehner works
with 10 p.ct. solutions; Chardonnet has continually aimed at higher concentration
up to 20 p.ct. Lehner has been able very much to reduce his pressures of ejection in
consequence; Chardonnet has had to increase up to pressures of 60 k. per cm. and
higher. The latter involves very costly distributing apparatus. Lehner made next
considerable advance by the discovery of the fact that the addition of sulphuric acid
to the collodion caused increase of fluidity (13), which Lehner attributes to

molecular change. Chardonnet found similar results from the addition of aldehyde
and other reagents (14), but not such as to be employed for the more concentrated
collodions. The author next refers to his discoveries (15) that alcoholic solutions of
a number of substances, organic and inorganic, freely dissolve the lower cellulose
nitrates. The most satisfactory of these substances is chloride of calcium (16). It is
noted that acetate of ammonia causes rapid changes in the solution, which appear to
be due to a species of hydrolysis. The result is sufficiently remarkable to call for
further investigation. The chloride of calcium, it is thought possible, produces a
direct combination of the alcohol with a reactive group of the nitrocellulose. The
fluidity of this solution using one mol. CaCl2 per 1 mol. tetranitrate (17) reaches a
maximum in half an hour's heating at 60°-70°C. The fluidity is increased by starting
from a cotton which has been previously mercerised. After nitration there is no
objection to a chlorine bleach. Chardonnet has found on the other hand that in
bleaching before nitration there is a loss of spinning quality in the collodion. The
author considers that the new collodion can be used entirely in place of the ordinary
ether-alcohol collodion. With regard to the properties of the denitrated products
they fix all basic colours without mordant and may be regarded as oxycellulose
therefore. The density of the thread is from 1.5 to 1.55. The thread of 100 deniers
shows a mean breaking strain of 120 grammes with an elasticity of 8-12 p.ct. The
cardinal defect of these fibres is their property of combination with water. Many
attempts have been made to confer water-resistance (18), but without success.
Strehlenert has proposed the addition of formaldehyde (19), but this is without
result (20). In reference to these effects of hydration, the author has made
observations on cotton thread, of which the following table represents the
numerical results:

Breaking Strain
Mean of 20
experiments
Skein of bleached cotton without treatment 825
Skein of bleached cotton without treatment, but
942
wetted
Ditto after conversion into hexanitrate, dry 884
The above, wetted 828
The cotton denitrated from above, dry 529
The cotton denitrated as above and wetted 206

The author considers that other patents which have been taken for spinning
nitrocellulose are of little practical account (21) and (22). The same
conclusion also applies to the process of Langhans, who proposes to spin
solutions of cellulose in sulphuric acid (23) (24) and mixtures of sulphuric
acid and phosphoric acid.
Group 2. Lustra-cellulose.—Thread prepared by spinning solutions of
cellulose in cuprammonium.
This product is made by the Vereinigte Glanzstoff-Fabriken, Aachen,
according to a series of patents under the names of H. Pauly, M. Fremery
and Urban, Consortium mulhousien pour la fabrication de fils brillants, E.
Bronnert, and E. Bronnert and Fremery and Urban (1). The first patent in
this direction was taken by Despeissis in 1890 (2). It appears this inventor
died shortly after taking the patent (3) The matter was later developed by
Pauly (4) especially in overcoming the difficulty of preparing a solution of
sufficient concentration. (It is to be noted that Pauly's patents rest upon a
very slender foundation, being anticipated in every essential detail by the
previous patent of Despeissis.) For this very great care is required,
especially, first, the condition of low temperature, and, secondly, a regulated
proportion of copper and ammonia to cellulose. The solution takes place
more rapidly if the cellulose has been previously oxidised. Such cellulose
gives an 8 p.ct. solution, and the thread obtained has the character of an
oxycellulose, specially seen in its dyeing properties. The best results are
obtained, it appears, by the preliminary mercerising treatment and placing
the alkali cellulose in contact with copper and ammonia. (All reagents

employed in molecular proportions.) The author notes that the so-called
hydrocellulose (Girard) (5) is almost insoluble in cuprammonium, as is
starch. It is rendered soluble by alkali treatment.
Group 3. Lustra-cellulose prepared by spinning a solution of cellulose in
concentrated chloride of zinc.
This solution has been known for a long time and used for making filaments
for incandescent lamps. The cellulose threads, however, have very little
tenacity. This is no doubt due to the conditions necessary for forming the
solution, the prolonged digestion causing powerful hydrolysis (1). Neither
the process of Wynne and Powell (2) nor that of Dreaper and Tompkins (3),
who have endeavoured to bring the matter to a practical issue, are
calculated to produce a thread taking a place as a textile. The author has
described in his American patent (4) a method of effecting the solution in
the cold, viz. again by first mercerising the cellulose and washing away the
caustic soda. This product dissolves in the cold and the solution remains
unaltered if kept at low temperature. Experiments are being continued with
these modifications of the process, and the author anticipates successful
results. The modifications having the effect of maintaining the high
molecular weight of the cellulose, it would appear that these investigations
confirm the theory of Cross and Bevan that the tenacity of a film or thread
of structureless regenerated cellulose is directly proportional to the
molecular weight of the cellulose, i.e. to its degree of molecular aggregation
(5).
Group 4. 'Viscose' silks obtained by spinning solutions of xanthate of
cellulose.
In 1892, Cross and Bevan patented the preparation of a new and curious
compound of cellulose, the thiocarbonate (1) (2) (3). Great hopes were
based upon this product at the time of its discovery. It was expected to yield
a considerable industrial and financial profit and also to contribute to the
scientific study of cellulose. The later patents of C. H. Stearn (4) describe
the application of viscose to the spinning of artificial silk. The viscose is
projected into solutions of chloride of ammonium and washed in a
succession of saline solutions to remove the residual sulphur impurities.
The author remarks that though it has a certain interest to have succeeded in

making a thread from this compound and thus adding another to the
processes existing for this purpose, he is not of opinion that it shows any
advance on the lustra-cellulose (2) and (3). He also considers that the
bisulphide of carbon, which must be regarded as a noxious compound, is a
serious bar to the industrial use of the process, and for economic work he
considers that the regeneration of ammonia from the precipitating liquors is
necessary and would be as objectionable as the denitration baths in the
collodion process. The final product not being on the market he does not
pronounce a finally unfavourable opinion.
The author and the Vereinigte Glanzstoff-Fabriken after long investigation
have decided to make nothing but the lustra-cellulose (2) and (3). A new
factory at Niedermorschweiler, near Mulhouse, is projected for this last
production.

BIBLIOGRAPHY

Introduction

(1) Bull. de la Soc. industr. de Mulhouse, 1900.
(2) Réaumur, Mémoire pour servir à l'histoire des insectes, 1874, 1, p. 154.
(3) English Pat. No. 283, Feb. 6, 1855.
(4) Swinburne, Electrician, 18, 28, 1887, p. 256.
(5) Weston (Swinburne), Electrician, 18, 1887, p. 287. Eng. Pat. No. 22866,
Sept. 12, 1882.
(6) German Pat. No. 3029. English Pat. No. 161780, April 28, 1884 (Swan).
(7) Wynne-Powell, English Pat. No. 16805, Dec. 22, 1884.

Group I

(1) German Pat No. 38368, Dec. 20, 1885. German Pat. No. 46125, March
4, 1888. German Pat. No. 56331, Feb. 6, 1890. German Pat. No. 81599,

Oct. 11, 1893. German Pat. No. 56655, April 23, 1890. French Pat. No.
231230, June 30, 1893.
(2) Industrie textile, 1899, 1892. Wyss-Noef, Zeitschrift für angewandte
Chemie, 1899, 30, 33. La Nature, Jan. 1, 1898, No. 1283. Revue générale
des sciences, June 30, 1898.
(3) German Pat. No. 46125, March 4, 1888. German Pat. No. 56655, April
23, 1890.
(4) Swan, English Pat. 161780, June 28, 1884. See also Béchamp, Dict. de
Chimie de Wurtz.
(5) German Pat. No. 81599, Oct 11, 1893.
(6) Béchamp, art. Cellulose, Dict. de Chimie de Wurtz, p. 781.
(7) Chardonnet, addit. March 3, 1897, to the French Pat. 231230, May 30,
1893.
(8) Knofler, French Pat. 247855, June 1, 1895. German Pat. 88556, March
28, 1894.
(9) Béchamp, art. Cellulose, Dict. de Chimie de Wurtz. Blondeau, Ann.
Chim. et Phys. (3), 1863, 68, p. 462.
(10) Revue industrielle, 1890, p. 194. German Pat. 52977, March 7, 1889.
(11) French Pat. 256854, June 2, 1896.
(12) German Pat. 55949, Nov. 9, 1889. German Pat. 58508, Sept. 16, 1890.
German Pat. 82555, Nov. 15, 1894.
(13) German Pat. 58508, Sept. 16, 1900.
(14) French Pat. 231230, June 30, 1893.
(15) German Pat. 93009, Nov. 19, 1895. French Pat. 254703, March 12,
1896. English Pat. 6858, March 28, 1896.
(16) American Pat. 573132, Dec. 15, 1896.

(17) This proportion is the most advantageous, and furnishes the best liquid
collodions that can be spun.
(18) French Pat. 259422, Sept. 3, 1896.
(19) English Pat. 22540, 1896.
(20) Application for German Pat. not granted, 4933 IV. 296, Mar. 16, 1897.
(21) German Pat. 96208, Feb. 10, 1897. Addit. Pat. 101844 and 102573,
Dec. 10, 1897.
(22) Oberle et Newbold, French Pat. 25828, July 22, 1896. Granquist, Engl.
applic. 2379, Nov. 28, 1899.
(23) German Pat. 72572, June 17, 1891.
(24) Voy. Stern, Ber., 28, ch. 462.

Group II

(1) German Pat. 98642, Dec. 1, 1897 (Pauly). French Pat. 286692, March
10, 1899, and addition of October 14, 1899 (Fremery and Urban). French
Pat. 286726, March 11, 1899, and addition of December 4, 1899. German
Pat. 111313, March 16, 1899 (Fremery and Urban). English Pat. 18884,
Sept. 19, 1899 (Bronnert). English Pat. 13331, June 27, 1899 (Consort.
mulhousien).
(2) French Pat. 203741, Feb. 12, 1890.
(3) The actual lapse of this patent is due to the death of Despeissis shortly
after it was taken.
(4) Without questioning the good faith of Pauly, it is nevertheless a fact that
the original patent remains as a document, and therefore that the value of
the Pauly patents is very questionable.
(5) Girard, Ann. Chim. et Phys, 1881 (5), 24, p. 337-384.

Group III

(1) Cross and Bevan, Cellulose, 1895, p. 8.
(2) English Pat. 16805, Dec. 22, 1884.
(3) English Pat. 17901, July 30, 1897.
(4) Bronnert, American Pat. 646799, April 3, 1900.
(5) Cross and Bevan, Cellulose, 1895, p. 12.

Group IV

(1) English Pat. 8700, 1892. German Pat. 70999, Jan. 13, 1893.
(2) English Pat. 4713, 1896. German Pat. 92590, Nov. 21, 1896.
(3) Comptes rendus (loc. cit.). Berichte, c. 9, 65a.
(4) English Pat. 1020, 1898. German Pat. 108511, Oct. 18, 1898.

Artificial Silk—Lustra-cellulose.

C. F. Cross and E. J. Bevan (J. Soc. Chem. Ind., 1896, 317).

The object of this paper is mainly to correct current statements as to the
artificial or 'cellulose silks' being explosive or highly inflammable (ibid.,
1895, 720). A specimen of the 'Lehner' silk was found to retain only 0.19
p.ct. total nitrogen, showing that the denitration is sufficiently complete to
dispose of any suggestion of high inflammability.
The product yielded traces only of furfural; on boiling with a 1 p.ct.
solution of sodium hydrate, the loss of weight was 9.14 p.ct.; but the
solution had no reducing action on Fehling's solution. The product in
denitration had therefore reverted completely to a cellulose (hydrate), no
oxy-derivative being present.

The authors enter a protest against the term 'artificial silk' as applied to
these products, and suggest 'lustra-cellulose.'

DIE KÜNSTLICHE SEIDE-IHRE HERSTELLUNG,
EIGENSCHAFTEN UND VERWENDUNG.

Carl Süvern, Berlin, 1900, J. Springer.

ARTIFICIAL SILK—ITS PRODUCTION, PROPERTIES,
AND APPLICATIONS.

This work of some 130 pages is an important monograph on the subject of
the preparation of artificial cellulose threads—so far as the technical
elements of the problems involved are discussed and disclosed in the patent
literature. The first section, in fact, consists almost exclusively of the
several patent specifications in chronological order and ranged under the
sub-sections: (a) The Spinning of Nitrocellulose (collodion); (b) The
Spinning of other Solutions of Cellulose; (c) The Spinning of Solutions of
the Nitrogenous Colloids.
In the second section the author deals with the physical and chemical
proportions of the artificial threads.
Chardonnet 'silk' is stated to have a mean diameter of 35µ, but with
considerable variations from the mean in the individual fibres; equally wide
variations in form are observed in cross-section. The general form is
elliptical, but the surface is marked by deep striæ, and the cross-section is
therefore of irregular outline. This is due to irregular conditions of
evaporation of the solvents, the thread being 'spun' into the air from
cylindrical orifices of regulated dimensions. Chardonnet states that when
the collodion is spun into alcohol the resultant thread is a perfect cylinder
(Compt. rend. 1889, 108, 962). The strength of the fibre is variously stated
at from 50-80 p.ct. that of 'boiled off' China tram; the true elasticity is 4-5
p.ct., the elongation under the breaking strain 15-17 p.ct. The sp.gr. is 1.49,
i.e. 3-5 p.ct. in excess of boiled off silk.

Lehner 'silk' exhibits the closest similarity to the Chardonnet product. In
cross-section it is seen to be more regular in outline, and a round, pseudo-
tubular form prevails, due to the conditions of shrinkage and collapse of the
fibre in parting with the solvents, and in then dehydrating. The constants for
'breaking strain,' both in the original and moistened condition, for elasticity,
&c., are closely approximate to those for the Chardonnet product.
Pauly 'silk'.—The form of the ultimate fibres is much more regular and the
contour of the cross-section is smooth. The product shows more resistance
to moisture and to alkaline solutions.
Viscose 'silk' is referred to in terms of a communication appearing in
'Papier-Zeitung,' 1898, 2416.
In the above section the following publications are referred to:
Chardonnet, 'Compt. rend.,' 1887, 105, 900; and 1889, 108, 962;
Silbermann, 'Die Seide,' 1897, v. 2, 143; Herzog, 'Farber-
Zeitung,' 1894/5, 49-50; Thiele, ibid. 1897, 133; O. Schlesinger,
'Papier-Zeitung,' 1895, 1578-81, 1610-12.

Action of Reagents upon Natural and Artificial Silks.

1. Potassium hydrate in solution of maximum concentration dissolves the
silks proper, (a) China silk on slight warming, (b) Tussah silk on boiling.
The cellulose 'silks' show swelling with discolouration, but the fibrous
character is not destroyed even on boiling.
2. Potassium hydrate 40 p.ct. China silk dissolves completely at 65°-85°;
Tussah silk swells considerably at 75° and dissolves at 100°-120°. The
cellulose 'silks' are attacked with discolouration; at 140° (boiling-point of
the solution) there is progressive solvent action, but the action is
incomplete. The Pauly product is most resistant.
3. Zinc chloride, 40 p.ct. solution. Both the natural silks and lustra-
celluloses are attacked at 100°, and on raising the temperature the further
actions are as follows: China silk is completely dissolved at 110-120°;
Tussah silk at 130-135°; the collodion products at 140-145°; the Pauly
product was again most resistant, dissolving at 180°.

4. Alkaline cupric oxide (glycerin) solution was prepared by dissolving 10
grs. of the sulphate in 100 c.c. water, adding 5 grs. glycerin and 10 c.c. of
40 p.ct. KOH. In this solution the China silk dissolved at the ordinary
temperature; Tussah silk and the lustra-celluloses were not appreciably
affected.
5. Cuprammonium solution was prepared by dissolving the precipitated
cupric hydrate in 24 p.ct. ammonia. In this reagent also the China silk
dissolved, and the Tussah silk as well as the lustra-celluloses underwent no
appreciable change.
6. An ammoniacal solution of nickel oxide was prepared by dissolving the
precipitated hydrated oxide in concentrated ammonia. The China silk was
dissolved by this reagent; Tussah silk and the lustra-celluloses entirely
resisted its action.
7. Fehling's solution is a solvent of the natural silks, but is without action
on the lustra-celluloses.
8. Chromic acid—20 p.ct. CrO3—solution dissolves both the natural silks
and the lustra-celluloses at the boiling temperature of the solution.
9. Millon's reagent, at the boiling solution, colours the natural silks violet:
the lustra-celluloses give no reaction.
10. Concentrated nitric acid attacks the natural silks powerfully in the cold;
the lustra-celluloses dissolve on heating.
11. Iodine solution (I in KI) colours the China silk a deep brown, Tussah a
pale brown; the celluloses from collodion are coloured at first brown, then
blue. The Pauly product, on the other hand, does not react.
12. Diphenylamine sulphate.—A solution of the base in concentrated
sulphuric acid colours the natural silks a brown; the collodion 'silks' give a
strong blue reaction due to the presence of residual nitro-groups. The Pauly
product is not affected.
13. Brucin sulphate in presence of concentrated sulphuric acid colours the
natural silks only slightly (brown); the collodion 'silks' give a strong red
colouration. The Pauly product again is without reaction.

14. Water.—The natural silks do not soften in the mouth as do the lustra-
celluloses.
15. Water of condition was determined by drying at 100°; the following
percentages resulted (a). The percentages of water (b) taken up from the
atmosphere after forty-three hours' exposure were:

(a) (b)
China (raw) silk 7.97 2.24
Tussah silk 8.26 5.00
Lustra-celluloses:
Chardonnet (Besançon) 10.375.64
" Spreitenbach 11.17 5.77
Lehner 10.715.97
Pauly 10.046.94

16. Behaviour on heating at 200°.—After two hours' heating at this
temperature the following changes were noted:

China silk Much discoloured (brown).
Tussah silk Scarcely affected.
Lustra-
celluloses:
Chardonnet Converted into a blue-black charcoal, retaining the form
Lehner of the fibres.
A bright yellow-brown colouration, without
Pauly
carbonisation.

17. The losses of weight accompanying these changes and calculated per
100 parts of fibre dried at 100° were:

China silk 3.18
Tussah silk 2.95

Lustra-celluloses:
Chardonnet 33.70
Lehner 26.56

Pauly 1.61

18. Inorganic constituents.—Determinations of the total ash gave for the
first five of the above, numbers varying from 1.0 to 1.7 p.ct. The only
noteworthy point in the comparison was the exceptionally small ash of the
Pauly product, viz. 0.096 p.ct.
19. Total nitrogen.—The natural silks contain the 16-17 p.ct. N
characteristic of the proteids. The lustra-celluloses contain 0.05-0.15 p.ct. N
which in those spun from collodion is present in the form of nitric groups.
The points of chemical differentiation which are established by the above
scheme of comparative investigation are summed up in tabular form.
Methods of dyeing.—The lustra-celluloses are briefly discussed. The
specific relationship of these forms of cellulose to the colouring matters are
in the main those of cotton, but they manifest in the dye-bath the somewhat
intensified attraction which characterises mercerised cotton, or more
generally the cellulose hydrates.
Industrial applications of the lustra-celluloses are briefly noticed in the
concluding section of the book.

FOOTNOTES:
[3] With these products it is easy to observe that they have a definite fusion point
5°-10° below the temperature of explosion.

SECTION III. DECOMPOSITIONS OF
CELLULOSE SUCH AS THROW LIGHT ON
THE PROBLEM OF ITS CONSTITUTION
UEBER CELLULOSE.

G. Bumcke und R. Wolffenstein (Berl. Ber., 1899, 2493).

(p. 54) Theoretical Preface.—The purpose of these investigations is the
closer characterisation of the products known as 'oxycellulose' and
'hydracellulose,' which are empirical aggregates obtained by various
processes of oxidation and hydrolysis; these processes act concurrently in
the production of the oxycelluloses. The action of hydrogen peroxide was
specially investigated. An oxycellulose resulted possessing strongly marked
aldehydic characteristics. The authors commit themselves to an explanation
of this paradoxical result, i.e. the production of a body of strongly 'reducing'
properties by the action of an oxidising agent upon the inert cellulose
molecule (? aggregate) as due to the hydrolytic action of the peroxide:
following Wurster (Ber. 22, 145), who similarly explained the production of
reducing sugars from cane sugar by the action of the peroxide.
The product in question is accordingly termed hydralcellulose. By the
action of alkalis this is resolved into two bodies of alcoholic (cellulose) and
acid ('acid cellulose') characteristics respectively. The latter in drying passes
into a lactone. The acid product is also obtained from cellulose by the action
of alkaline lye (boiling 30 p.ct. NaOH) and by solution in Schweizer's
reagent.
It is considered probable that the cellulose nitrates are hydrocellulose
derivatives, and experimental evidence in favour of this conclusion is
supplied by the results of 'nitrating' the celluloses and their oxy- and hydro-
derivatives. Identical products were obtained.

Experimental investigations.—The filter paper employed as 'original
cellulose,' giving the following numbers on analysis:

C 44.5644.2944.5344.56
H 6.39 6.31 6.46 6.42

was exposed to the action of pure distilled H2O2 at 4-60 p.ct. strength, at
ordinary temperatures until disintegrated: a result requiring from nineteen to
thirty days. The series of products gave the following analytical results:

C 43.6143.6143.4643.8944.043.8743.9243.81
H 6.00 6.29 6.28 6.266.13 6.27 6.24 6.27

results lying between the requirements of the formulæ:
5 C6H10O5.H2O and 8 C6H10O5.H2O.

Hydrazones were obtained with 1.7-1.8 p.ct. N. Treated with caustic soda
solution the hydrazones were dissolved in part: on reprecipitation a
hydrazone of unaltered composition was obtained. The original product
shows therefore a uniform distribution of the reactive CO- groups.
The hydralcellulose boiled with Fehling's solution reduced 1/12 of the
amount required for an equal weight of glucose.
Digested with caustic soda solution it yielded 33 p.ct. of its weight of the
soluble 'acid cellulose.' This product was purified and analysed with the
following result: C 43.35 H 6.5. For the direct production of the 'acid'
derivative, cellulose was boiled with successive quantities of 30 p.ct. NaOH
until dissolved. It required eight treatments of one hour's duration. On
adding sulphuric acid to the solutions the product was precipitated. Yield 40
p.ct. Analyses:

C 43.843.843.7
H 6.2 6.2 6.3

The cellulose reprecipitated from solution in Schweizer's reagent gave
similar analytical results:

C 43.943.844.0
H 6.5 6.3 6.4

Conversion into nitrates.—The original cellulose, hydral- and acid cellulose
were each treated with 10 times their weight of HNO3 of 1.48 sp.gr. and
heated at 85° until the solution lost its initial viscosity.
The products were precipitated by water and purified by solution in acetone
from which two fractions were recovered, the one being relatively insoluble
in ethyl alcohol. The various nitrates from the several original products
proved to be of almost identical composition,
C 32.0 H 4.2 N 8.8
with a molecular weight approximately 1350. The conclusion is that these
products are all derivatives of a 'hydralcellulose' 6 C6H10O5H2O.

FORMATION OF FURFURALDEHYDE FROM
CELLULOSE, OXYCELLULOSE, AND
HYDROCELLULOSE.

By Leo Vignon (Compt. rend., 1898, 126, 1355-1358).

(p. 54) Hydrocellulose, oxycellulose, and 'reduced' cellulose, the last named
being apparently identical with hydrocellulose, were obtained by heating
carefully purified cotton wool (10 grams) in water (1,000 c.c.), with (1) 65
c.c. of hydrochloric acid (1.2 sp.gr.), (2) 65 c.c. of hydrochloric acid and 80
grams of potassium chlorate, (3) 65 c.c. of hydrochloric acid and 50 grams
of stannous chloride. From these and some other substances, the following
percentage yields of furfuraldehyde were obtained: Hydrocellulose, 0.854;
oxycellulose, 2.113; reduced cellulose, 0.860; starch, 0.800; bleached
cotton, 1.800; oxycellulose, prepared by means of chromic acid, 3.500. Two
specimens of oxycellulose were prepared by treating cotton wool with
hydrochloric acid and potassium chlorate (A), and with sulphuric acid and
potassium dichromate (B), and 25 grams of each product digested with
aqueous potash. Of the product A, 16.20 grams were insoluble in potash,
2.45 grams were precipitated on neutralisation of the alkaline solution, and

6.35 grams remained in solution, whilst B yielded 11.16 grams of insoluble
matter, 1.42 grams were precipitated by acid, and 12.42 grams remained in
solution. The percentage yields of furfuraldehyde obtained from these
fractions were as follows: A, insoluble, 0.86; precipitated, 4.35; dissolved,
1.10. B, insoluble, 0.76; precipitated, 5.11; dissolved, 1.54. It appears, from
the foregoing results, that the cellulose molecule, after oxidation, is easily
decomposed by potash, the insoluble and larger portion having all the
characters of the original cellulose, whilst the soluble portion is of an
aldehydic nature, and contains a substance, precipitable by acids, which
yields a relatively large amount of furfuraldehyde.

UNTERSUCHUNGEN ÜBER DIE OXYCELLULOSE.

O. v. Faber und B. Tollens (Berl. Ber., 1899, 2589).

Investigations of Oxycellulose.

(p. 61) The author's results are tersely summed up in the following
conclusions set forth at the end of the paper: The oxycelluloses are mixtures
of cellulose and a derivative oxidised compound which contains one more
atom O than cellulose (cellulose = C6H10O5), and for which the special
designation Celloxin is proposed.
Celloxin may be formulated C8H6O6 or C6H10O6, of which the former is
the more probable.
The various oxycelluloses may be regarded as containing one celloxin
group to 1-4 cellulose groups, according to the nature of the original
cellulose, and the degree of oxidation to which subjected. These groups are
in chemical union.
Celloxin has not been isolated. On boiling the oxycelluloses with lime-milk
it is converted into isosaccharinic and dioxybutyric acids. The insoluble
residue from the treatment is cellulose.
The following oxycelluloses were investigated:

A. Product of action of nitric acid upon pine wood (Lindsey and Tollens,
Ann. 267, 366).—The oxycelluloses contained
1 mol celloxin: {2 mol. cellulose on 6 hours' heating
{3 mol. cellulose on 3 hours' heating
with a ratio H: O = 1: 9 and 1: 8.7 respectively: they yielded 7 p.ct. furfural.
B. By action of bromine in presence of water and CaCO3 upon cotton.—
Yield, (air-dry) 85 p.ct. Empirical composition C12H20O11 =
C6H10O5.C6H10O6: yielded furfural 1.7 p.ct.

C. Cotton and nitric acid at 100°, two and a half hours (Cross and Bevan).
—Yield, 70 p.ct. Composition
4 C6H10O5.C6H8O6

yielded furfural 2.3 p.ct.
D. Cotton and nitric acid at 100° (four hours).—A more highly oxidised
product resulted, viz. 3 C6H10O5.C6H8O6: yielded furfural 3.2 p.ct.

By-products of oxidation.—The liquors from B were found to contain
saccharic acid: the acid from C and B contained a dibasic acid which
appeared to be tartaric acid.
The isolation of (1) isosaccharinic and (2) dioxybutyric acid from the
products of digestion of the oxycelluloses with lime-milk at 100° was
effected by the separation of their respective calcium salts, (1) by direct
crystallisation, (2) by precipitation alcohol after separation of the former.

CELLULOSES, HYDRO- AND OXYCELLULOSES, AND
CELLULOSE ESTERS.

L. Vignon (Bull. Soc. Chim., 1901 [3], 25, 130).

(a) Oxycelluloses from cotton, hemp, flax, and ramie.—The comparative
oxidation of these celluloses, by treatment with HClO3 at 100°, gave
remarkably uniform results, as shown by the following numbers, showing

extreme variations: yields, 68-70 p.ct.; hydrazine reaction, N fixed 1.58-
1.69; fixation of basic colouring matters (relative numbers), saffranine, 100-
200, methylene blue, 100-106. The only points of difference noted were (1)
hemp is somewhat more resistant to the acid oxidation; (2) the cotton
oxycellulose shows a somewhat higher (25 p.ct.) cupric reduction.
(b) 'Saccharification' of cellulose, cellulose hydrates, and hydrocellulose.—
The products were digested with dilute hydrochloric acid six hours at 100°,
and the cupric reduction of the soluble products determined and calculated
to dextrose.

gave reducing products equal to
100 grms. of
Dextrose
Purified cotton 3.29
" Hydrocellulose 9.70
Cotton mercerised (NaOH 30° B.) 4.39
Cotton mercerised (NaOH 40° B.) 3.51
Cellulose reprecipitated from
4.39
cuprammonium
Oxycellulose 14.70
Starch 98.6

These numbers show that cellulose may be hydrated both by mercerisation
and solution, without affecting the constitutional relationships of the CO
groups. The results also differentiate the cellulose series from starch in
regard to hydrolysis.
(c) Cellulose and oxycellulose nitrates.—The nitric esters of cellulose have
a strong reducting action on alkaline copper solutions. The author has
studied this reaction quantitatively for the esters both of cellulose and
oxycellulose, at two stages of 'nitration,' represented by 8.2-8.6 p.ct. and
13.5-13.9 p.ct. total nitrogen in the ester-products, respectively. The results
are expressed in terms (c.c.) of the cupric reagent (Pasteur) reduced per 100
grs. compared with dextrose (=17767).

Cellulose maximum nitration (13.5 p.ct. N) 3640
Oxycellulose maximum nitration (13.9 p.ct. N) 3600

Cellulose minimum nitration (8.19 p.ct. N) 3700
Oxycellulose minimum nitration (8.56 p.ct. N) 3620

The author concludes that, since the reducing action is independent of the
degree of nitration, and is the same for cellulose and the oxycelluloses, the
ester reaction in the case of the normal cellulose is accompanied by
oxidation, the product being an oxycellulose ester.
Products of 'denitration'.—The esters were treated with ferrous chloride in
boiling aqueous solution. The products were oxycelluloses, with a cupric
reduction equal to that of an oxycellulose directly prepared by the action of
HClO3. On the other hand, by treatment with ammonium sulphide at
35°-40° 'denitrated' products were obtained without action on alkaline
copper solutions.

OXYCELLULOSES AND THE MOLECULAR WEIGHT OF
CELLULOSE.

H. Nastukoff (Berl. Ber. 33 [13] 2237).

(p. 61) The author continues his investigations of the oxidation of cellulose.
[Compare Bull. Mulhouse, 1892.] The products described were obtained by
the action of hypochlorites and permanganates upon Swedish filter paper
(Schleicher and Schüll).
4. Oxidation by hypochlorites.—(1) The cellulose was digested 24 hrs. with
35 times its weight of a filtered solution of bleaching power of 4°B.;
afterwards drained and exposed for 24 hrs. to the atmosphere. These
treatments were then repeated. After washing, treatment with dilute acetic
acid and again washing, the product was treated with a 10 p.ct. NaOH
solution. The oxycellulose was precipitated from the filtered solution: yield
45 p.ct. The residue when purified amounted to 30 p.ct. of the original
cellulose, with which it was identical in all essential properties.
The oxycellulose, after purification, dried at 110°, gave the following
analytical numbers:

C 43.6443.7843.3243.13
H 6.17 6.21 5.98 6.08

Its compound with phenylhydrazine (loc. cit.) gave the following analytical
numbers:

N 0.780.960.84

(2) The reagents were as in (1), but the conditions varied by passing a
stream of carbonic acid gas through the solution contained in a flask, until
Cl compounds ceased to be given off. The analysis of the purified
oxycellulose gave C 43.53, H 6.13.
(3) The conditions were as in (2), but a much stronger hypochlorite solution
—viz. 12°B.—was employed. The yield of oxycellulose precipitated from
solution in soda lye (10 p.ct. NaOH) was 45 p.ct. There was only a slight
residue of unattacked cellulose. The analytical numbers obtained were:

Oxycellulose C 43.31 43.74 43.69
" H 6.47 6.42 6.51
________________________
Phenylhydrazine compound N 0.62 0.81

B. Oxidation by permanganate (KMnO4). (1) The cellulose 16 grms. was
treated with 1100 c.c. of a 1 p.ct. solution of KMnO4 in successive portions.
The MnO2 was removed from time to time by digesting the product with a
dilute sulphuric acid (10 p.ct. H2SO4). The oxycellulose was purified as
before, yield 40 p.ct. Analytical numbers:

Oxycellulose C 42.1242.9
" H 6.20 6.11
________________________
Phenylhydrazine compound N 1.35 1.08 1.21

(2) The cellulose (16 grms.) was digested 14 days with 2500 c.c. of 1 p.ct.
KMnO4 solution. The purified oxycellulose was identical in all respects
with the above: yield 40 p.ct. C 42.66, H 6.19.

(3) The cellulose (16 grms.) was heated in the water-bath with 1600 c.c. of
15 p.ct. H2SO4 to which were added 18 grms. KMnO4. The yield and
composition of the oxycellulose was identical with the above. It appears
from these results that the oxidation with hypochlorites acids 1 atom of O to
4-6 of the unit groups C6H10O5; and the oxidation with permanganate 2
atoms O per 4-6 units of C6H10O5. The molecular proportion of N in the
phenylhydrazine residue combining is fractional, representing 1 atom O, i.e.
1 CO group reacting per 4 C36H60O31 and 6 C24H49O21 respectively,
assuming the reaction to be a hydrazone reaction.
Further investigations of the oxycelluloses by treatment with (a) sodium
amalgam, (b) bromine (water), and (c) dilute nitric acid at 110°, led to no
positive results.
By treatment with alcoholic soda (NaOH) the products were resolved into a
soluble and insoluble portion, the properties of the latter being those of a
cellulose (hydrate).
Molecular weight of cellulose and oxycellulose.—The author endeavours to
arrive at numbers expressing these relations by converting the substances
into acetates by Schutzenberger's method, and observing the boiling-points
of their solution in nitrobenzene.

FERMENTATION OF CELLULOSE

V. Omelianski (Compt. Rend., 1897, 125, 1131-1133).

Pure paper was allowed to ferment in the presence of calcium carbonate at a
temperature of 35° for 13 months. The products obtained from 3.4743
grams of paper were: acids of the acetic series, 2.2402 grams; carbonic
anhydride, 0.9722 grams; and hydrogen, 0.0138 gram. The acids were
chiefly acetic and butyric acid, the ratio of the former to the latter being 1.7:
1. Small quantities of valeric acid, higher alcohols, and odorous products
were formed.
The absence of methane from the products of fermentation is remarkable,
but the formation of this gas seems to be due to a special organism readily

distinguishable from the ferment that produces the fatty acids. This
organism is at present under investigation.

(p. 75) Constitution of Cellulose.—It may be fairly premised that the
problem of the constitution of cellulose cannot be solved independently of
that of molecular aggregation. We find in effect that the structural properties
of cellulose and its derivatives are directly connected with their
constitution. So far we have only a superficial perception of this correlation.
We know that a fibrous cellulose treated with acids or alkalis in such a way
that only hydrolytic changes can take place is converted into a variety of
forms of very different structural characteristics, and these products, while
still preserving the main chemical characteristics of the original, show when
converted into derivatives by simple synthesis, e.g. esters and
sulphocarbonates, a corresponding differentiation of the physical properties
of these derivatives, from the normal standard, and therefore that the new
reacting unit determines a new physical aggregate. Thus the
sulphocarbonate of a 'hydrocellulose' is formed with lower proportions of
alkaline hydrate and carbon disulphide, gives solutions of relatively low
viscosity, and, when decomposed to give a film or thread of the regenerated
cellulose, these are found to be deficient in strength and elasticity. Similarly
with the acetate. The normal acetate gives solutions of high viscosity, films
of considerable tenacity, and when those are saponified the cellulose is
regenerated as an unbroken film. The acetates of hydrolysed celluloses
manifest a retrogradation in structural and physical properties, proportioned
to the degree of hydrolysis of the original.
We may take this opportunity of pointing out that the celluloses not only
suggest with some definiteness the connection of the structural properties of
visible aggregates—that is, of matter in the mass—with the configuration of
the chemical molecule or reacting unit, but supply unique material for the
actual experimental investigation of the problems involved. Of all the
'organic' colloids cellulose is the only one which can be converted into a
variety of derivative forms, from each of which a regular solid can be
produced in continuous length and of any prescribed dimensions. Thus we
can compare the structural properties of cellulose with those of its hydrates,

nitrates, acetates, and benzoates, in terms of measurements of breaking
strain, extensibility, elasticity. Investigations in this field are being
prosecuted, but the results are not as yet sufficiently elaborated for
reduction to formulæ. One striking general conclusion is, however,
established, and that is that the structural properties of cellulose are but little
affected by esterification and appear therefore to be a function of the special
arrangement of the carbon atoms, i.e. of the molecular constitution. Also it
is established that the molecular aggregate which constitutes a cellulose is
of a resistant type, and undoubtedly persists in the solutions of the
compounds.
It may be urged that it is superfluous to import these questions of mass-
aggregation into the problem of the chemical constitution of cellulose. But
we shall find that the point again arises in attempting to define the reacting
unit, which is another term for the molecule. In the majority of cases we
rely for this upon physical measurements; and in fact the purely chemical
determination of such quantities is inferential. Attempts have been made to
determine the molecular weights of the cellulose esters in solution, by
observations of depression of solidifying and boiling-points. But the
numbers have little value. The only other well-defined compound is the
sulphocarbonate. It has been pointed out that, by successive precipitations
of this compound, there occurs a continual aggregation of the cellulose with
dissociation of the alkali and CS residues and it has been found impossible
to assign a limit to the dissociation, i.e. to fix a point at which the transition
from soluble sulphocarbonate to insoluble cellulose takes place.
On these grounds it will be seen we are reduced to a somewhat speculative
treatment of the hypothetical ultimate unit group, which is taken as of C6
dimensions.
As there has been no addition of experimental facts directly contributing to
the solution of the problem, the material available for a discussion of the
probabilities remains very much as stated in the first edition, pp. 75-77. It is
now generally admitted that the tetracetate n [C6H6O.(OAc)4] is a normal
cellulose ester; therefore that four of the five O atoms are hydroxylic. The
fifth is undoubtedly carbonyl oxygen. The reactions of cellulose certainly
indicate that the CO- group is ketonic rather than aldehydic. Even when
attacked by strong sulphuric acid the resolution proceeds some considerable

way before products are obtained reducing Fehling's solution. This is not
easily reconcilable with any polyaldose formula. Nor is the resistance of
cellulose to very severe alkaline treatments. The probability may be noted
here that under the action of the alkaline hydrates there occurs a change of
configuration. Lobry de Bruyn's researches on the change of position of the
typical CO- group of the simple hexoses, in presence of alkalis, point very
definitely in this direction. It is probable that in the formation of alkali
cellulose there is a constitutional change of the cellulose, which may in
effect be due to a migration of a CO- position within the unit group. Again
also we have the interesting fact that structural changes accompany the
chemical reaction. It is surprising that there should have been no
investigation of these changes of external form and structure, otherwise
than as mass effects. We cannot, therefore, say what may be the molecular
interpretation of these effects. It has not yet been determined whether there
are any intrinsic volume changes in the cellulose substance itself: and as
regards what changes are determined in the reacting unit or molecule, we
can only note a fruitful subject for future investigation. A priori our views
of the probable changes depend upon the assumed constitution of the unit
group. If of the ordinary carbohydrate type, formulated with an open chain,
there is little to surmise beyond the change of position of a CO- group. But
alternative formulæ have been proposed. Thus the tetracetate is a derivative
to be reckoned with in the problem. It is formed under conditions which
preclude constitutional changes within the unit groups. The temperature of
the main reaction is 30°-40°, the reagents are used but little in excess of the
quantitative proportions, and the yields are approximately quantitative. If
now the derivative is formed entirely without the hydrolysis the empirical
formula C6H6O.(OAc)4 justifies a closed-ring formula for the original viz.
CO<[CHOH]4>CH2; and the preference for this formula depends upon the
explanation it affords of the aggregation of the groups by way of CO-CH2
synthesis.
The exact relationship of the tetracetate to the original cellulose is
somewhat difficult to determine. The starting-point is a cellulose hydrate,
since it is the product obtained by decomposition of the sulphocarbonate.
The degree of hydrolysis attending the cycle of reactions is indicated by the
formula 4 C6H10O5.H2O. It has been already shown that this degree of
hydrolysis does not produce molecular disaggregation. If this hydrate

survived the acetylation it would of course affect the empirical composition,
i.e. chiefly the carbon percentage, of the product. It may be here pointed out
that the extreme variation of the carbon in this group of carbohydrate esters
is as between C14H20O10 (C = 48.3 p.ct.) and C14H18O9 (C = 50.8 p.ct.) i.e.
a tetracetate of C6H12O6 and C6H10O5 respectively. In the fractional
intermediate terms it is clear that we come within the range of ordinary
experimental errors, and to solve this critical point by way of ultimate
analysis must involve an extended series of analyses with precautions for
specially minimising and quantifying the error. The determination of the
acetyl by saponification is also subject to an error sufficiently large to
preclude the results being applied to solve the point. While, therefore, we
must defer the final statement as to whether the tetracetate is produced from
or contains a partly hydrolysed cellulose molecule, it is clear that at least a
large proportion of the unit groups must be acetylated in the proportion
C6H6O.(OAc)4.

It has been shown that by the method of Franchimont a higher proportion of
acetyl groups can be introduced; but this result involves a destructive
hydrolysis of the cellulose: the acetates are not derivatives of cellulose, but
of products of hydrolytic decomposition.
It appears, therefore, that with the normal limit of acetylation at the
tetracetate the aggregation of the unit groups must depend upon the CO-
groups and a ring formula of the general form CO<[CHOH]4>CH2 is
consistent with the facts.
Vignon has proposed for cellulose the constitutional formula
with reference to the highest nitrate, and the
decomposition of the nitrate by alkalis with
formation of hydroxypyruvic acid. While
these reactions afford no very sure ground
for deductions as to constitutional
relationships, it certainly appears that, if the aldose view of the unit group is
to be retained, this form of the anhydride contains suggestions of the
general tendency of the celluloses on treatment with condensing acids to
split off formic acid in relatively large quantity [Ber. 1895, 1940]; the
condensation of the oxycelluloses to furfural; the non-formation of the

normal hydroxy-dicarboxylic acids by nitric acid oxidations. Indirectly we
may point out that any hypothesis which retains the polyaldose view of
cellulose, and so fails to differentiate its constitution from that of starch, has
little promise of progress. The above formula, moreover, concerns the
assumed unit group, with no suggestion as to the mode of aggregation in the
cellulose complex. Also there is no suggestion as to how far the formula is
applicable to the celluloses considered as a group. In extending this view to
the oxycelluloses, Vignon introduces the derived oxidised group
—of which one is apportioned to
three or four groups of the
cellulose previously formulated:
these groups in condensed union
together constitute an oxycellulose.
These views are in agreement with the experimental results obtained by
Faber and Tollens (p. 71). They regard the oxycelluloses as compounds of
'celloxin' C6H_8{O}6 with 1-4 mols. unaltered cellulose; and the former
they particularly refer to as a lactone of glycuronic acid. But on boiling with
lime they obtain dioxybutyric and isosaccharinic acids; both of which are
not very obviously related to the compounds formulated by Vignon. We
revert with preference to a definitely ketonic formula, for which, moreover,
some farther grounds remain to be mentioned. In the systematic
investigation of the nitric esters of the carbohydrates (p. 41) Will and Lenze
have definitely differentiated the ketoses from the aldoses, as showing an
internal condensation accompanying the ester reaction. Not only are the OH
groups taking part in the latter consequently less by two than in the
corresponding aldoses, but the nitrates show a much increased stability.
This would give a simple explanation of the well-known facts obtaining in
the corresponding esters of the normal cellulose. We may note here that an
important item in the quantitative factors of the cellulose nitric ester
reaction has been overlooked: that is, the yield calculated to the NO3 groups
fixed. The theoretical yields for the higher nitrates are

Yield p.ct. of cellulose N p.ct. of nitrate
Pentanitrate 169 12.7
Hexanitrate 183 14.1

From such statistics as are recorded the yields are not in accordance with
the above. There is a sensible deficiency. Thus Will and Lenze record a
yield of 170 p.ct. for a product with 13.8 p.ct. N, indicating a deficiency of
about 10 p.ct. As the by-products soluble in the acid mixture are extremely
small, the deficiency represents approximately the water split off by an
internal reaction. In this important point the celluloses behave as ketoses.
In the lignocelluloses the condensed constituents of the complex are of
well-marked ketonic, i.e. quinonic, type. In 'nitrating' the lignocelluloses
this phenomenon of internal condensation is much more pronounced (see p.
131). As the reaction is mainly confined to the cellulose of the fibre, we
have this additional evidence that the typical carbonyl is of ketonic
function. It is still an open question whether the cellulose constituents of the
lignocelluloses are progressively condensed—with progress of
'lignification'—to the unsaturated or lignone groups. There is much in
favour of this view, the evidence being dealt with in the first edition, p. 180.
The transition from a cellulose-ketone to the lignone-ketone involves a
simple condensation without rearrangement; from which we may argue
back to the greater probability of the ketonic structure of the cellulose. We
must note, however, that the celluloses of the lignocelluloses are obtained as
residues of various reactions, and are not homogeneous. They yield on
boiling with condensing acids from 6 to 9 p.ct. furfural. It is usual to regard
furfural as invariably produced from a pentose residue. But this
interpretation ignores a number of other probable sources of the aldehyde. It
must be particularly remembered that lævulose is readily condensed (a) to a
methylhydroxyfurfural
C6H1O6 - 3H2O = C6H6O3 = C5(OH).H2.(CH3)O2

and (b) by HBr, with further loss of OH, as under:
C6H12O6 - 4H2O + HBr = C5H3(CH2Br)O

and generally the ketoses are distinguished from the aldoses by their
susceptibility to condensation. Such condensation of lævulose has been
effected by two methods: (a) by heating the concentrated aqueous solution
with a small proportion of oxalic acid at 3 atm. pressure [Kiermayer, Chem.
Ztg. 19, 100]; (b) by the action of hydrobromic acid (gas) in presence of

anhydrous ether; the actual compound obtained being the ω-brommethyl
derivative [Fenton, J. Chem. Soc. 1899, 423].
This latter method is being extended to the investigation of typical
celluloses, and the results appear to confirm the view that cellulose may be
of ketonic constitution.
The evidence which is obtainable from the synthetical side of the question
rests of course mainly upon the physiological basis. There are two points
which may be noted. Since the researches of Brown and Morris (J. Chem.
Soc. 1893, 604) have altered our views of the relationships of starch and
cane sugar to the assimilation process, and have placed the latter in the
position of a primary product with starch as a species of overflow and
reserve product, it appears that lævulose must play an important part in the
elaboration of cellulose. Moreover, A. J. Brown, in studying the cellulosic
cell-collecting envelope produced by the Bacterium xylinum, found that the
proportion of this product to the carbohydrate disappearing under the action
of the ferment was highest in the case of lævulose. These facts being also
taken into consideration there is a concurrence of suggestion that the typical
CO group in the celluloses is of ketonic character. That the typical cotton
cellulose breaks down finally under the action of sulphuric acid to dextrose
cannot be held to prove the aldehydic position of the carbonyls in the unit
groups of the actual cellulose molecule or aggregate.
We again are confronted with the problem of the aggregate and as to how
far it may affect the constitution of the unit groups. That it modifies the
functions or reactivity of the ultimate constituent groups we have seen from
the study of the esters. Thus with the direct ester reactions the normal
fibrous cellulose (C6H16O5) yields a monoacetate, dibenzoate, and a
trinitrate respectively under conditions which determine, with the simple
hexoses and anhydrides, the maximum esterification, i.e. all the OH groups
reacting. If the OH groups are of variable function, we should expect the
CO groups a fortiori to be susceptible of change of function, i.e. of position
within the unit groups.
But as to how far this is a problem of the constitution or phases of
constitution of the unit groups or of the aggregate under reaction we have as
yet no grounds to determine.

The subjoined communication, appearing after the completion of the MS. of
the book, and belonging to a date subsequent to the period intended to be
covered, is nevertheless included by reason of its exceptional importance
and special bearing on the constitutional problem above discussed.

THE ACTION OF HYDROGEN BROMINE ON
CARBOHYDRATES.[4]

H. J. H. Fenton and Mildred Gostling (J. Chem. Soc., 1901, 361).

The authors have shown in a previous communication (Trans., 1898, 73,
554) that certain classes of carbohydrates when acted upon at the ordinary
temperature with dry hydrogen bromide in ethereal solution give an intense
and beautiful purple colour.[5] It was further shown (Trans., 1899, 75, 423)
that this purple substance, when neutralised with sodium carbonate and
extracted with ether, yields golden-yellow prisms of ω-brommethylfurfural,

This reaction is produced by lævulose, sorbose, cane sugar, and inulin, an
intense colour being given within an hour or two. Dextrose, maltose, milk
sugar, galactose, and the polyhydric alcohols give, if anything, only
insignificant colours, and these only after long standing. The authors
therefore suggested that the reaction might be employed as a means of
distinguishing these classes of carbohydrates, the rapid production of the
purple colour being indicative of ketohexoses, or of substances which
produce these by hydrolysis.
By relying only on the production of the purple colour, however, a mistake
might possibly arise, owing to the fact that xylose gives a somewhat similar

colour after standing for a few hours. Hence, the observations should be
confirmed by isolation of the crystals of brommethylfurfural. No trace of
this substance is obtained from the xylose product.
In order to identify the substance, the ether extract, after neutralisation, is
allowed to evaporate to a syrup, and crystallisation promoted either by
rubbing with a glass rod, or by the more certain and highly characteristic
method of 'sowing' with the most minute trace of ω-brommethylfurfural,
when crystals are almost instantly formed. These are recrystallised from
ether, or a mixture of ether and light petroleum, and further identified by the
melting-point (59.5-60.5°), and, if considered desirable, by estimation of
the bromine.
It is now found, so reactive is the bromine atom in this compound, that the
estimation may be accurately made by titration with silver nitrate according
to Volhard's process, the crystals for this purpose being dissolved in dilute
alcohol:
0.1970 gram required 10.5 c.c. N/10 AgNO3. Br = 42.63 p.ct., calculated
42.32 p.ct.
This method of applying hydrogen bromide in ethereal solution is, of
course, unsuitable for investigations where a higher temperature has to be
employed, or where long standing is necessary, since, under such
circumstances, the ether itself is attacked. Wishing to make investigations
under these conditions, the authors have tried several solvents, and, at
present, find that chloroform is best suited to the purpose. In each of the
following experiments, 10 grms. of the substance were covered with 250
c.c. of chloroform which had been saturated at 0° with dry hydrogen
bromide. The mixture was contained in an accurately stoppered bottle,
firmly secured with an iron clamp, and heated in a water-bath to about the
boiling temperature for two hours. After standing for several hours, the
mixture was treated with sodium carbonate (first anhydrous solid, and
afterwards a few drops of strong solution), filtered, and the solution dried
over calcium chloride. Most of the chloroform was then distilled off, and
the remaining solution allowed to evaporate to a thick syrup in a weighed
dish.

The product was then tested for ω-brommethylfurfural by 'sowing' with the
most minute trace of the substance, as described above. It was then warmed
on a water-oven, kept in a vacuum desiccator over solid paraffin, and the
weight estimated. When necessary, the product was recrystallised from
ether, and further identified by the tests mentioned. The following results
were obtained:

Weight of crude residue.
Swedish filter paper 3.0 crystallised at once by 'sowing.'
Ordinary cotton 3.3 " "
Mercerised cotton 2.1 " "
[6] 2.3 " "
Straw cellulose
Lævulose 2.2 " "
Inulin 1.3 " "
Potato starch 0.37 " "
Cane sugar 0.85 " "
Dextrose 0.33 uncrystallisable.
Milk sugar 0.37 "
Glycogen 0.34 "
Galactose 0.34 "

The products from dextrose, milk sugar, and galactose absolutely refused to
crystallise even when extracted with ether and again evaporated, or by
'sowing,' stirring, &c.
The glycogen product deposited a very small amount of crystalline matter
on standing, but the quantity was too minute for examination; moreover, it
refused altogether to crystallise in contact with the aldehyde. It may fairly
be stated, therefore, that these last four substances give absolutely negative
results as regards the formation of ω-brommethylfurfural; if any is formed,
its quantity is altogether too small to be detected.
The specimen of starch examined was freshly prepared from potato, and
purified by digestion for twenty-four hours each with N/10 KOH, N/4 HCl,
and strong alcohol; it was then washed with water and allowed to dry in the
air. It will be seen that this substance gave a positive result, but that the
yield was extremely small, and might yet be due to impurity. Considering

the importance of the behaviour of starch, for the purpose of drawing
general conclusions from these observations, it was thought advisable to
make further experiments with specimens which could be relied upon, and
also to investigate the behaviour of dextrin. This the authors have been
enabled to do upon a series of specimens specially prepared by C.
O'Sullivan, and thus described by him:
1. Rice starch, specially purified by the permanganate method.
2. Wheat starch " " "
3. Oat starch, contains traces of oil, washed with dilute KOH
and dilute HCl.
4. Pea starch, first crop, washed with alkali, acid (HCl), and
strong alcohol.
5. Natural dextrin, D = 3.87, αD = 194.7; K = 0.95, (c 2.628).

6. α-Dextrin, C equation purified without fermentation, 30
precipitations with alcohol (Trans., 1879, 35, 772).
The examination of these specimens was conducted on a smaller scale, but
under the same conditions as before, one gram of the substance being
treated with 12.5 c.c. of the saturated chloroform solution and heated in
sealed tubes for two hours as above. The results were as follows:

Weight of crude residue.
1. Rice starch 0.046 crystallised at once by 'sowing.'
2. Wheat starch 0.044 " "
3. Oat starch 0.049 " "
4. Pea starch 0.064 " "
5. Natural dextrin 0.088 " "
6. α-Dextrin 0.055 " "

The results may therefore be summarised as follows:—Treated under these
particular conditions all forms of cellulose give large yields of ω-
brommethylfurfural, some varieties giving as much as 33 per cent.
Lævulose, inulin, and cane sugar give yields varying from 22 to 8.5 per

cent.; various starches give small yields (average about 4.5 per cent.); and
dextrins 5 to 8 per cent., whereas dextrose, milk sugar, and galactose give,
apparently, none at all.
The yields represent the solid crystalline residue; this when purified by
recrystallisation gives, probably, about three-quarters of its weight of pure
crystals. (In the case of dextrose, &c., the yields represent the weight of
syrup.)
These numbers, however, by no means represent the maximum yields
obtainable, owing to the comparatively slight solubility of hydrogen
bromide in chloroform. The process was conducted in the above manner
only for the sake of uniform comparison. The ether method previously
described gives much larger yields; for example, 12 grms. of inulin treated
with only 60 c.c. of the saturated ether gave 2.5 grms. of substance. For the
purpose of obtaining larger yields, other methods are being investigated.
The facts recorded above, taken in conjunction with those given in our
previous communications, appear to point definitely to the following
general conclusions. First, that the various forms of cellulose contain one or
more groups or nuclei identical with that contained in lævulose, and that
such groups constitute the main or essential part of the molecule. Secondly,
that similar groupings are contained in starches and dextrins, but that the
proportion of such groupings represents a relatively small part of the whole
structure.
The nature of this grouping is, according to the generally accepted
constitution of lævulose, the six-carbon chain with a ketonic group:

But the results might, on the other hand, be considered indicative of the
anhydride or 'lacton' grouping, which Tollens suggested for lævulose:

The latter very simply represents the formation of ω-brommethylfurfural
from lævulose,[7]

giving

although by a little further 'manipulation' of the symbols the change could,
of course, be represented by reference to the ketonic formula.

The Ketonic Constitution of Cellulose.

C. F. Cross and E. J. Bevan (J. Chem. Soc., 1901, 366).

In this paper the authors discuss more fully the theoretical bearings of the
observations of Fenton and Gostling, the two papers being simultaneously
communicated. The paper is mainly devoted to a review of the antecedent
evidence, chemical and physiological, and to a general summing up in
favour of the view that cellulose is a polyketose (anhydride).

(p. 79) Composition of the Seed Hair of Eriodendron (Anf.)—Some
interest attaches to the results of an analytical investigation which we have
made of this silky floss. There is little doubt that cotton is entirely
exceptional in its characteristics: both in structure and chemical
composition it fails to show any adaptation to what we may regard as the
more obvious functions of a seed hair—which certainly do not demand
either structural strength or chemical resistance. The following numbers
determined for the kapok differentiate it widely from the cottons:
Ash, 1.3; moisture, 9.3; alkaline hydrolysis (loss) (a) 16.7, (b)
21.8. Cellulose, by chlorination, &c., 71.1.
In reacting with chloride it shows the presence of unsaturated groups,
similar to the lignone of the woods. This was confirmed by a well-marked
reaction with ferric ferricyanide with increase of weight due to the fixation
of the blue cyanide.
But the most characteristic feature is the high yield of furfural on boiling
with condensing acids. The following numbers were determined:

Total furfural from original fibre 14.84
In residue from alkali hydrolysis 11.5
In cellulose isolated by Cl method 10.4

Treated with sulphuric acids of concentration, (a) 92.1 grs. H2SO4 per 100
c.c., (b) 105.8 grs. per 100 c.c., the fibres dissolve, and diluted immediately
after complete solution it was resolved into

(a) (b)
Reprecipitated fraction 68.743.7
Soluble fraction yielding furfural 13.214.3

By these observations it is established that the furfuroids are of the cellulose
type and behave very much as the furfuroids of the cereal celluloses.
This group of seed hairs invites exhaustive investigation. The furfuroid
constituents are easily isolated, and as they constitute at least one-third of

the fibre substance it is especially from this point of view that they invite
study.

RECHERCHES SUR L'OXYCELLULOSE.

L. Vignon.

Résumé of investigations (1898-1900) of Oxycellulose,
published as a brochure (Rey, Lyon, 1900).

(a) A typical oxycellulose prepared from cotton cellulose by the action of
HClO3 (HCl + KClO3) in dilute solution at 100° for one hour gave the
following numbers:

C H O
Elementary composition 43.55 6.03 50.42
Original
Oxycellulose
cellulose
Analysis by Lange's method
Soluble in KOH (at 180°) 87.6 12.0
Insoluble in KOH (at 180°) 12.4 88.0
Original
Oxycellulose
cellulose
Heat of combustion 4124-4133 4190-4224
Heat evolved in contact with 50
times wt. normal KOH per 100 1.3 cal. 0.74 cal.
grms.
Oxycellulose Cellulose
Absorption of colouring matters at
Saffranine 0.7 0.0
100° per 100 grms.
Methylene
0.6 0.2
blue

(b) Yield of furfural from cellulose, oxy- and hydro-cellulose.—From the
hydrocelluloses variously prepared the author obtains 0.8 p.ct. furfural;

from bleached cotton 1.8 p.ct.; and from the oxycelluloses variously
prepared 2.0-3.5 p.ct. The 'furfuroid' is relatively more soluble in alkaline
solutions (KOH) in the cold. The insoluble residue is a normal cellulose.
(c) Nitrates of cellulose, oxy- and hydro-cellulose.—Treated with the usual
acid mixture (H2SO4 3 p., HNO3 1 p.) under conditions for maximum
action, the resulting esters showed uniformly a fixation of 11.0 NO2 groups
per unit mol. of C24. The oxycellulose nitrate was treated directly with
dilute solution of potassium hydrate in the cold. From the products of
decomposition the author obtained the osazone of hydroxypyruvic acid
[Will, Ber. 24, 400].
(d) Osazones of the oxycelluloses.—Oxycelluloses prepared by various
methods are found to fix varying proportions of phenylhydrazine (residue),
viz. from 3.4-8.5 p.ct. of the cellulose derivative reacting, corresponding
with, i.e. calculated from, the nitrogen determined in the products (0.87-2.2
p.ct.). The reaction is assumed to be that of osazone formation.
The author has also established a relation between the phenylhydrazine
fixed and the furfural which the substance yields on boiling with
condensing acids. This is illustrated by the subjoined series of numbers:

Fixed p.ct. formed p.ct.
Cotton (bleached) 1.73 1.60
Oxycellulose (HClO3) 7.94 2.09
" (HClO) 3.37 1.79
" (CrO3) (1) 7.03 3.00
" (CrO3) (2) 7.71 3.09
" (CrO3) (3) 8.48 3.50

(e) Constitution of cellulose and oxycellulose.—The results of these
investigations are generalised as regards cellulose (C_6) by the
constitutional formula

The oxycelluloses contain the characteristic group

in union with varying proportions of residual cellulose.

QUANTITATIVE SEPARATION OF CELLULOSE-LIKE
CARBOHYDRATES IN VEGETABLE SUBSTANCES.

Wilhelm Hoffmeister (Landw. Versuchs-Stat., 1897, 48, 401-411).

To separate the hemicelluloses, celluloses, and the constituents of lignin
without essential change, the substance, after being freed from fat, is
extracted with dilute hydrochloric acid and ammonia, and the residue
frequently agitated for a day or two with 5-6 p.ct. caustic soda solution. It is
then diluted, the extract poured off, neutralised with hydrochloric acid,
treated with sufficient alcohol, and the hemicellulose filtered, dried, and
weighed. The residue from the soda extract is washed on a filter with hot
water, and extracted with Schweizer's reagent.
When the final residue (lignin) is subjected to prolonged extraction with
boiling dilute ammonia (a suitable apparatus is described, with sketch) until
the ammonia is no longer coloured, a residue is obtained which mostly
dissolves in Schweizer's reagent, and on repeating the process the residue is
found to consist largely of mineral matter. The dissolved cellulose-like
substances often contain considerable amounts of pentosanes.
According to the nature of the substance, the extraction with ammonia may
take weeks, or months, or even longer; the ammonia extracts of hard woods
(as lignum vitæ) and of cork are dark brown, and give an odour of vanilla

when evaporated down. The residues, which are insoluble in water, but
redissolve in ammonia, have the properties of humic acids. Other vegetable
substances, when extracted, yielded, besides humic acids, a compound,
C6H7O2, soluble in alcohol and chloroform, but insoluble in water, ether,
and benzene; preparations from different sources melted between 200° and
210°.

FOOTNOTES:
[4] The original paper is reproduced with slight alterations.
[5] This purple colour would appear to be due to a highly dissociable compound
of ω-brommethylfurfural with hydrogen bromide. The aldehyde gives yellow or
colourless solutions in various solvents, which are turned purple by a sufficient
excess of hydrogen bromide. Dilution, or addition of water, at once discharges
the colour.
[6] Other forms of cellulose were also examined—for example, pinewood
cellulose—and the substances separated from solution as thiocarbonate (powder
and film). All of these gave good yields of ω-brommethylfurfural.
[7] The change is empirically represented as
C6H12O6 + HBr - 4H2O = C6H5O2Br.

SECTION IV. CELLULOSE GROUP,
INCLUDING HEMICELLULOSES AND
TISSUE CONSTITUENTS OF FUNGI
VERSUCHE ZUR BESTIMMUNG DES GEHALTS EINIGER
PFLANZEN UND PFLANZENTEILE AN
ZELLWANDBESTANDTEILEN AN HEMICELLULOSEN
UND AN CELLULOSE.

A. Kleiber (Landw. Vers.-Stat., 1900, 54, 161).

ON THE DETERMINATION OF CELL-WALL
CONSTITUENTS, HEMICELLULOSES AND CELLULOSE
IN PLANTS AND PLANT TISSUES.

In a preliminary discussion the author critically compares the results of
various of the methods in practice for the isolation and estimation of
cellulose. The method of F. Schulze [digestion with dil. HNO3 with KClO3
—14 days, and afterwards treating the product with ammonia, &c.] is stated
to be the 'best known' (presumably the most widely practised); W.
Hoffmeister's modification of the above, in which the nitric acid is replaced
by hydrochloric acid (10 p.ct. HCl) is next noted as reducing the time of
digestion from 14 days to 1-2 days, and giving in many cases higher yields
of cellulose. The methods of treating with the halogens, viz. bromine water
(H. Müller), chlorine gas (Cross and Bevan), and chlorine water, are
dismissed with a bare mention, apparently on the basis of the conclusions of
Suringar and Tollens (q.v.). The method of Lange, the basis of which is a
'fusion' with alkaline hydrates at 180°, and the modified method of Gabriel,
in which the 'fusion' with alkali takes place in presence of glycerin, are
favourably mentioned.

These methods were applied to a range of widely different raw materials to
determine, by critical examination of the products, both as regards yield and
composition, what title these latter have to be regarded as 'pure cellulose.'
This portion of the investigation is an extension of that of Suringar and
Tollens, these latter confining themselves to celluloses of the 'normal'
groups, i.e. textile and paper-making celluloses. The present communication
is a study of the tissue and cell-wall constituents of the following types:—
1. Green plants of false oat grass (Arrhenatherium, E.).
2. Green plants of lucerne (Medicago sativa).
3. Leaves of the ash (Fraxinus).
4. Leaves of the walnut (Juglans).
5. Roots of the purple melic grass (Molinia cærulea).
6. Roots of dandelion (Taraxacum officinale).
7. Roots of comfrey.
8. Coffee berries.
9. Wheat bran.
These raw materials were treated for the quantitative estimation of cellulose
by the method of Lange (b), Hoffmeister (c), and Schulze (d), and the
numbers obtained are referred for comparison to the corresponding yields
of 'crude fibre' (Rohfaser) by the standard method (a).
As a first result the author dismisses Lange's method as hopeless: the results
in successive determinations on the same materials showing variations up to
60 p.ct. The results by c and d are satisfactorily concordant: the yields of
cellulose are higher than of 'crude fibre.' This is obviously due to the
conservation of 'hemicellulose' products, which are hydrolysed and
dissolved in the treatments for 'crude fibre' estimation. A modified method
was next investigated, in which the process of digestion with acid chloroxy-
compounds (c and d) was preceded by a treatment with boiling dilute acid.
The yields of cellulose by this method (e) are more uniform, and show less
divergence from the numbers for 'crude fibre.'
The author's numerical results are given in a series of tables which include
determinations of proteids and ash constituents, and the corresponding
deductions from the crude weight in calculating to 'pure cellulose.' The
subjoined extract will illustrate these main lines of investigation.

Crude Fibre Pure Cellulose
Raw Weende Hoffmeister Hoffmeister, modified by
Material Method. Method. Author.
(a) (c) (e)
Oat grass 30.35 34.9 31.5
Lucerne 25.25 28.7 20.5
Leaves of
13.05 15.4 13.8
ash
Roots of
21.60 29.1 21.4
melic
Coffee
18.30 35.1 23.3
beans
Bran 8.2 19.3 9.3

The final conclusion drawn from these results is that the method of
Hoffmeister yields a product containing variable proportions of
hemicelluloses. These are eliminated by boiling with a dilute acid (1.25
p.ct. H2SO4), which treatment may be carried out on the raw material—i.e.
before exposure to the acid chlorate, or on the crude cellulose as ordinarily
isolated.
Determination of Tissue-constituents.—By the regulated action of certain
solvents applied in succession, it appears that such constituents of the plant-
complex can be removed as have no organic connection with the cellular
skeleton: the residue from such treatments, conversely, fairly represents the
true tissue-constituents. The author employs the method of digestion with
cold dilute alkaline solutions (0.15 to 0.5 p.ct. NaOH), followed by
exhaustive washing with cold and hot water, afterwards with cold and hot
alcohol, and finally with ether.
The residue is dried and weighed as crude product. When necessary, the
proportions of ash and proteid constituents are determined and deducted
from the 'crude product' which, thus corrected, may be taken as representing
the 'carbohydrate' tissue constituents.
Determination of Hemicelluloses.—By the process of boiling with dilute
acids (1.25 p.ct. H2SO4) the hemicelluloses are attacked—i.e. hydrolysed

and dissolved. The action of the acid though selective is, of course, not
exclusively confined to these colloidal carbohydrates. The proteid and
mineral constituents are attacked more or less, and the celluloses
themselves are not entirely resistant to the action. The loss due to the latter
may be neglected, but in calculating the hemicellulose constants from the
gross loss the proteids and mineral constituents require to be taken into
account in the usual way.

QUANTITATIVE SEPARATION OF HEMICELLULOSE,
CELLULOSE, AND LIGNIN. PRESENCE OF PENTOSANES
IN THESE SUBSTANCES.

Wilhelm Hoffmeister (Landw. Versuchs-Stat, 1898, 50, 347-362).

(p. 88) The separation of the cellulose-like carbohydrates of sunflower
husks is described.
In order to ascertain the effect of dilute ammonia on the cellulose
substances of lignin, a dried 5 p.ct. caustic soda extract was extracted
successively with 1, 2, 3, and 4 p.ct. sodium hydroxide solution. Five grams
of the 2 p.ct. extract were then subjected to the action of ammonia vapour;
the cellulose did not completely dissolve in six weeks. Cellulose insoluble
in caustic soda (32 grms.) was next extracted with ammonia, in a similar
manner, for 10 days, dried, and weighed. 30.46 grms. remained, which,
when treated with 5 p.ct. aqueous caustic soda, yielded 0.96 grm. (3 per
cent.) of hemicellulose.
When cellulose is dissolved in Schweizer's solution, the residue is, by
repeated extraction with aqueous sodium hydroxide, completely converted
into the soluble form. On evaporating the ammonia from the Schweizer's
extract, at the ordinary temperature and on a water-bath respectively,
different amounts of cellulose are obtained; more hemicellulose is obtained,
by caustic soda, from the heated solution than from that which was not
heated. In this operation the pentosanes are more influenced than the
hexosanes; pentosanes are not always readily dissolved by caustic soda, and
hexosanes are frequently more or less readily dissolved. Both occur in

lignin, and are then undoubtedly indigestible. These points have to be
considered in judging the digestibility of these carbohydrates.
A comparison of analyses of clover, at different periods, in the first and
second years of growth, shows that both cellulose (Schweizer's extract) and
lignin increase in both constituents. In the second year the lignin alone
increased to the end; the cellulose decreased at the end of June. In the first
year it seemed an absolutely as well as relatively greater amount of
cellulose, and lignin was produced in the second year; this, however,
requires confirmation. The amount of pentosanes in the Schweizer extract
was relatively greater in the second than in the first year, but decreased in
the lignin more in the second year than in the first: this result is also given
with reserve.

DIE CONSTITUTION DER CELLULOSEN DER
CEREALIEN.

C. F. Cross, E. J. Bevan, and C. Smith (Berl. Ber., 1896, 1457).

THE CONSTITUTION OF THE CEREAL CELLULOSES.

(p. 84) Straw cellulose is resolved by two methods of acid hydrolysis into a
soluble furfural-yielding fraction, and an insoluble fraction closely
resembling the normal cellulose. (a) The cellulose is dissolved in sulphuric
acids of concentration, H2SO4.2H2O, H2SO4.3H2O. As soon as solution is
complete, the acid is diluted. A precipitate of cellulose hydrate (60-70 p.ct.)
is obtained, and the filtered solution contains 90-95 p.ct. of the furfuroids of
the original cellulose. The process is difficult to control, however, in mass,
and to obtain the latter in larger quantity the cellulose (b) is digested with
six times its weight of 1 p.ct. H2SO4 at 3 atm. pressure, the products of the
action being (1) a disintegrated cellulose retaining only a small fraction
(1/12) of the furfural-yielding groups, and (2) a slightly coloured solution of
the hydrolised furfuroids. An investigation of the latter gave the following
results: By oxidation with nitric acid no saccharic acid was obtained;
showing the absence of dextrose. The numbers for cupric reduction were in
excess of those obtained with the hexoses. The yield of ozazone was high,

viz. 30 to 40 p.ct. of the weight of the carbohydrate in solution. On
fractionating, the melting-points of the fractions were found to lie between
146° and 153°. Ultimate analysis gave numbers for C, H, and N identical
with those of a pentosazone. The product of hydrolysis appears, therefore,
to be xylose or a closely related derivative.
All attempts to obtain a crystallisation of xylose from the solution
neutralised (BaCO3), filtered, and evaporated, failed. The reaction with
phloroglucol and HCl, moreover, was not the characteristic red of the
pentoses, but a deep violet. The product was then isolated as a dry residue
by evaporating further and drying at 105°. Elementary analysis gave the
numbers C 44.2, 44.5, and H 6.7, 6.3. Determinations of furfural gave 39.5
to 42.5 p.ct. On treating the original solution with hydrogen peroxide, and
warming, oxidation set in, with evolution of CO2. This was estimated (by
absorption), giving numbers for CO2, 19.5, 20.5, 20.1 p.ct. of the substance.

The sum of these quantitative data is inconsistent with a pentose or
pentosane formula; it is more satisfactorily expressed by the empirical
formula

which represents a pentose monoformal. Attempts to synthesise a
compound of this formula have been so far without success.

UEBER EINIGE CHEMISCHE VORGÄNGE IN DER
GERSTENPFLANZE.

C. F. Cross, E. J. Bevan, and C. Smith (Berl. Ber., 1895, 2604).

THE CHEMICAL LIFE-HISTORY OF THE BARLEY
PLANT.

(p. 84) Owing to the presence of 'furfuroids' in large proportion as
constituents of the tissues of the stems of cereals, these plants afford

convenient material for studying the problem of the constitution of the
tissue-furfuroids, as well as their relationship to the normal celluloses. The
growing barley plant was investigated at successive periods of growth.
Yield of furfural was estimated on the whole plant and on the residue from
a treatment with alkaline and acid solvents in the cold such as to remove all
cell contents. This residue is described as 'permanent tissue.' The
observations were carried out through two growing seasons—1894-5—
which were very different in character, the former being rainy with low
temperature, the latter being abnormal in the opposite direction, i.e.
minimum rainfall and maximum sunshine. The barley selected for
observation was that of two experimental plots of the Royal Agricultural
Society's farm, one (No. 1) remaining permanently unmanured, and
showing minimum yield, the other (No. 6) receiving such fertilising
treatment as to give maximum yields.
The numerical results are given in the annexed tables:

BARLEY CROP, WOBURN, 1894.

Furfural from
permanent
Furfural Permanent tissue
Age of Dry
Date Plot p.ct. of dry tissue p.ct.
Crop Weight P.ct. P.ct. of
weight(a) dry weight Ratio
of entire
a:c
tissue plant
1.03 :
1 19.4 7.0 53.4 12.7 6.8
6 1
May 7
weeks 1.23 :
6 14.7 7.0 55.9 10.3 5.7
1
1.26 :
1 17.6 7.7 52.9 11.6 6.1
10 1
June 4
weeks 1.04 :
6 13.5 8.1 58.5 13.4 7.8
1
July 10 15 1.40 :
1 42.0 9.0 65.7 9.8 6.4
weeks 1

1.30 :
6 32.9 10.6 65.7 12.5 8.2
1
1.18 :
1 64.0 11.9 70.0 14.5 10.1
Cut 21 1
Aug. 21 weeks 1.26 :
6 64.6 13.4 70.5 15.0 10.6
1
1.02 :
1 84.0 12.7 75.0 16.5 12.4
Carried 22 1
Aug. 31 weeks 1.05 :
6 86.4 12.4 78.4 15.1 11.8
1
BARLEY CROP, WOBURN, 1895.
1.20 :
1 20.6 6.6 53.9 10.2 5.5
7 1
May 15
weeks 1.07 :
6 17.8 5.8 56.7 9.6 5.4
1
1.42 :
1 34.6 8.0 38.2 14.7 5.6
12 1
June 18
weeks 1.14 :
6 33.4 7.6 44.5 15.0 6.7
1
1.33 :
1 52.8 12.1 55.6 16.3 9.1
16 1
July 16
weeks 1.20 :
6 54.4 10.6 46.2 19.1 8.8
1
1.10 :
1 66.8 9.2 49.1 17.0 8.3
20 1
Aug. 16
weeks 1.04 :
6 65.0 9.8 49.8 19.1 9.4
1
1.31 :
1 84.3 10.4 45.7 17.6 8.0
22 1
Sept. 3
weeks 1.30 :
6 86.3 10.2 45.3 17.3 7.8
1

The variations exhibited by these numbers are significant. It is clear, on the
other hand, that the assimilation of the furfuroids does not vary in any
important way with variations in conditions of atmosphere and soil
nutrition. They are essentially tissue-constituents, and only at the flowering

period is there any accumulation of these compounds in the alkali-soluble
form. It has been previously shown (ibid. 27, 1061) that the proportion of
furfuroids in the straw-celluloses of the paper-maker differs but little from
that of the original straws. For the isolation of the celluloses the straws are
treated by a severe process of alkaline hydrolysis, to which, therefore, the
furfuroid groups offer equal resistance with the normal hexose groups with
which they are associated in the complex.
The furfuroids of the cereal straws are therefore not pentosanes. They are
original products of assimilation, and not subject to secondary changes after
elaboration such as to alter either their constitution or their relationship to
the normal hexose groups of the tissue-complex.

(1) CONSTITUTION OF THE CEREAL CELLULOSES

(Chem. Soc. J. 1896, 804).

(2) THE CARBOHYDRATES OF BARLEY STRAW

(Chem. Soc. J. 1896, 1604).

(3) THE CARBOHYDRATES OF THE CEREAL

STRAWS (Chem. Soc. J. 1897, 1001).

(4) THE CARBOHYDRATES OF BARLEY STRAW

(Chem. Soc. J. 1898, 459).

C. F. cross, E. J. Bevan, and Claud Smith.

These are a series of investigations mainly devoted to establishing the
identity of the furfural-yielding group which is a characteristic constituent.
This 'furfuroid' while equally resistant to alkalis as the normal cellulose
group with which it is associated, is selectively hydrolysed by acids. Thus

straw cellulose dissolves in sulphuric acids of concentration H2SO4.2H2O -
H2SO4.3H2O, and on diluting the normal cellulose is precipitated as a
hydrate, and the furfuroid remains in solution. But this sharp separation is
difficult to control in mass. By heating with a very dilute acid (1 p.ct.
H2SO4) the conditions are more easily controlled, the most satisfactory
results being obtained with 15 mins. heating at 3 atm. pressure.
(1) Operating in this way upon brewers' grains the furfuroid was obtainable
as the chief constituent of a solution for which the following experimental
numbers were determined:—Total dissolved solids, 28.0 p.ct. of original
'grains'; furfural, 39.5 p.ct. of total dissolved solids, as compared with 12.5
p.ct. of total original grains; cupric reduction (calc. to total solids), 110
(dextrose = 100) osazone; yield in 3 p.ct. solution, 35 p.ct. of weight of total
solids.

Pentosazone
Analysis N 17.1 17.317.07
C 62.5 62.362.2
H 6.4 6.5 6.1
Melting-point 146°-153°

From these numbers it is seen that of the total furfuroids of the original
'grains' 84 p.ct. are thus obtained in solution in the fully hydrolysed form,
which is that of a pentose or pentose derivative. It was, however, found
impossible to obtain any crystallisation from the neutralised (BaCO3) and
concentrated solution, the syrup being kept for some weeks in a desiccator.
It was noted at the same time that the colour reaction of the original
solution with phloroglucol and hydrochloric acid was a deep violet, in
contradistinction to the characteristic red of the pentoses. On oxidation with
hydrogen peroxide, in the proportion of 1 mol. H2O2 to 1 mol. of the
carbohydrate in solution, carbonic anhydride was formed in quantity = 20.0
p.ct. of the latter.
Fermentation (yeast) experiments also showed a divergence from the
resistant behaviour of the pentoses, a considerable proportion of the
furfuroid disappearing in a normal fermentation.

(2) The quantitative methods above described were employed in
investigating the barley plant at different stages of its growth. The green
plant was extracted with alcohol, the residue freed from alcohol and
subjected to acid hydrolysis.
The hydrolysed extract was neutralised and fermented. In the early stages of
growth the furfuroids were completely fermented, i.e. disappeared in the
fermentation. In the later stages this proportion fell to 50 p.ct. In the earlier
stages, moreover, the normal hexose constituents of the permanent tissue
were hydrolysed in large proportion by the acid, whereas in the matured
straw the hydrolysis is chiefly confined to the furfuroids. In the early stages
also the permanent tissue yields an extract with relatively low cupric
reduction, showing that the carbohydrates are dissolved by the acid in a
more complex molecular condition.
These observations confirm the view that the furfuroids take origin in a
hexose-pentose series of transformations. The proportion of furfuroid
groups to total carbohydrates varies but little, viz. from 1/3 in the early
stages to a maximum of 1/4 at the flowering period. At this period the
differentiation of the groups begins to be marked.
Taking all the facts of (1) and (2), they are not inconsistent with the
hypothesis of an internal transformation of a hexose to a pentose-
monoformal. Such a change of position and function of oxygen from OH to
CO within the group —CH.OH— is a species of internal oxidation which
reverses the reduction of formaldehyde groups in synthesising to sugars,
and appears therefore of probable occurrence.
These constitutional problems are followed up in (3) by the indirect method
of differentiating the relationships of these furfuroids to yeast fermentation,
from those of the pentoses. Straw and esparto celluloses are subjected to the
processes of acid hydrolysis, and the neutralised extracts fermented. With
high furfural numbers indicating that the furfuroids are the chief
constituents of the extract, there is an active fermentation with production
of alcohol. The cupric reduction falls in greater ratio to the original
(unfermented) than the furfural. Observations on the pure pentoses—xylose
and arabinose added to dextrose solutions, and then exposed to yeast action
—show that in a vigorous fermentation not unduly prolonged the pentoses

are unaffected, but that they do come within the influence of the yeast-cell
when the latter is in a less vigorous condition, and when the hexoses are not
present in relatively large proportion.
(4) The observations on the growing plant were resumed with the view of
artificially increasing the differentiation of the two main groups of
carbohydrates. From a portion of a barley crop the inflorescence was
removed as soon as it appeared. The crop was allowed to mature, and a full
comparison instituted between the products of normal and abnormal
growth. With a considerable difference in 'permanent tissue' (13 p.ct. less)
and a still greater defect in cellulose (24 p.ct.), the constants for the
furfuroids in relation to total carbohydrates were unaffected by the arrested
development. This was also true of the behaviour of the hydrolysed extracts
(acid processes) to yeast fermentation.
(5) The extract obtained from the brewers' grains by the process described
in (2) was investigated in relation to animal digestion. It has been now
generally established that the furfuroids as constituents of fodder plants are
digested and assimilated in large proportion in passing through animal
digestive tracts, and in this respect behave differently from the pentoses.
The furfuroids being obtained, as described, in a fully hydrolysed condition
(monoses) the digestion problem presented itself in a new aspect, and was
therefore attacked.
The result of the comparative feeding experiments upon rabbits was to
show that in this previously hydrolysed form the furfuroids are almost
entirely digested and assimilated, no pentoses, moreover, appearing in the
urine.
Generally we may sum up the present solution of the problem of the
relationship of the furfuroids to plant assimilation and growth as follows:—
The pentoses are not produced as such in the process of assimilation; but
furfural-yielding carbohydrates are produced directly and in approximately
constant ratio to the total carbohydrates; they are mainly located in the
permanent tissue; in the secondary changes of dehydration, &c.,
accompanying maturation they undergo such differentiation that they
become readily separable by processes of acid hydrolysis from the more
resistant normal celluloses; but in relation to alkaline treatments they

maintain their intimate union with the latter. They are finally converted into
pentoses by artificial treatments, and into pentosanes in the plant, with loss
of 1 C atom in an oxidised form. The mechanism of this transformation of
hexoses into pentoses is not cleared up. It is independent of external
conditions, e.g. fertilisation and atmospheric oxidations, and is probably
therefore a process of internal rearrangement of the character of an
oxidation.

ZUR KENNTNISS DER IN DEN MEMBRANEN DER PILZE
ENTHALTENEN BESTANDTHEILE.

E. Winterstein (Ztschr. Physiol. Chem., 1894, 521; 1895, 134).

ON THE CONSTITUENTS OF THE TISSUE OF FUNGI.

(p. 87) These two communications are a contribution of fundamental
importance, and may be regarded as placing the question of the composition
of the celluloses of these lowest types on a basis of well-defined fact. In the
first place the author gives an exhaustive bibliography, beginning with the
researches of Braconnot (1811), who regarded the cellular tissue of these
organisms as a specialised substance, which he termed 'fungin.' Payen
rejects this view, and regards the tissue, fully purified by the action of
solvents, as a cellulose (C6H10O5). This view is successively supported by
Fromberg [Mulder, Allg. Phys. Chem., Braunschweig, 1851], Schlossberger
and Doepping [Annalen, 52, 106], and Kaiser. De Bary, on a review of the
evidence, adopts this view, but, as the purified substance fails to give the
characteristic colour-reactions with iodine, he uses the qualifying term
'pilzcellulose' [Morph. u. Biol. d. Pilze u. Flechten, Leipzig, 1884].
C. Richter, on the other hand, shows that these reactions are merely a
question of methods of purification or preparation [Sitzungsber. Acad.
Wien, 82, 1, 494], and considers that the tissue-substance is an ordinary
cellulose, with the ordinary reactions masked by the presence of impurities.
In regard to the lower types of fungoid growth, such as yeast, the results of
investigators are more at variance. The researches of Salkowski (p. 113)
leave little doubt, however, that the cell-membrane is of the cellulosic type.

The author's researches extend over a typical range of products obtained
from Boletus edulis, Agaricus campestris, Cantharellus cibarius, Morchella
esculenta, Polyporus officinalis, Penicillium glaucum, and certain
undetermined species. The method of purification consisted mainly in (a)
exhaustive treatments with ether and boiling alcohol, (b) digestion with
alkaline hydrate (1-2 p.ct. NaOH) in the cold, (c) acid hydrolysis (2-3 p.ct.
H2SO4) at 95°-100°, followed by a chloroxidation treatment by the
processes of Schulze or Hoffmeister, and final alkaline hydrolysis.
The products, i.e. residues, thus obtained were different in essential points
from the celluloses isolated from the tissues of phanerogams similarly
treated. Only in exceptional cases do they give blue reactions with iodine in
presence of zinc chloride or sulphuric acid. The colourations are brown to
red. They resist the action of cuprammonium solutions. They are for the
most part soluble in alkaline hydrate solution (5-10 p.ct. NaOH) in the cold.
They give small yields (1-2 p.ct.) of furfural on boiling with 10 p.ct.
HCl.Aq.
Elementary analyses gave the following results, which are important in
establishing the presence of a notable proportion of nitrogen, which has
certainly been overlooked by the earlier observers:—

'Cellulose' or residue from C H N
Boletus edulis (Schulze process) 42.46.53.9
Boletus edulis (Hoffmeister process) 44.66.33.6
Polyporus off. 43.76.50.7
Cantharellus cib. 44.96.83.0
Agaricus campestris 44.36.63.6
Botrytis 42.16.33.9
Penicillium glaucum — — 3.3
Morchella esculenta — — 2.5

It is next shown that this residual nitrogen is not in the form of residual
proteids (1) by direct tests, all of which gave negative results, and (2)
indirectly by the high degree of resistance to both alkaline and acid
hydrolysis. The 'celluloses' are attacked by boiling dilute acids (1 p.ct.
H2SO4), losing in weight from 10 to 23 p.ct., the dissolved products having

a cupric reduction value about 50 p.ct. that of an equal weight of dextrose.
As an extreme hydrolytic treatment the products were dissolved in 70 p.ct.
H2SO4, allowed to stand 24 hours, then considerably diluted (to 3 p.ct.
H2SO4) and boiled to complete the inversion. The yields of glucose,
calculated from the cupric reduction, were as follows:—

Boletus edulis 65.2p.ct.
Polyporus off. 94.7 "
Agaricus campestris 59.1 "
Morchella esculenta 60.1 "
Cantharellus cib. 64.9 "
Botrytis 60.8 "

It will be noted that the exceptionally high yield from the Polyporus
cellulose is correlated with its exceptionally low nitrogen. By actual
isolation of a crystalline dextrorotary sugar, by preparations of osazone and
conversion into saccharic acid, it was proved that dextrose was the main
product of hydrolysis. The second main product was shown to be acetic
acid, the yield of which amounted to 8 p.ct. in several cases.
Generally, therefore, it is proved that the more resistant tissue constituents
of the fungi are not cellulose, but a complex of carbohydrates and
nitrogenous groups in combination, the former being resolved into glucoses
by acid hydrolysis, and the latter yielding acetic acid as a characteristic
product of resolution together with the nitrogenous groups in the form of an
uncrystallisable syrup.
In the further prosecution of these investigations (2) the author proceeded
from the supposition of the identity of the nitrogenous complex of the
original with chitin, and adopted the method of Ledderhose (Ztschr.
Physiol. Chem. 2, 213) for the isolation of glucosamin hydrochloride,
which he succeeded in obtaining in the crystalline form. In the meantime E.
Gilson had shown that these tissue substances in 'fusion' with alkaline
hydrates yield a residue of a nitrogenous product (C14H28N2O10), which is
soluble in dilute acids [Recherches Chim. sur la Membrane Cellulaire des
Champignons, La Cellule, v. II, pt. 1]. This residue, which was termed
mycosin by Gilson, has been similarly isolated by the author. It is proved,

therefore, that the tissues of the fungi do contain a product resembling
chitin. [See also Gilson, Compt. Rend. 120, 1000.] This constituent is in
intimate union with the carbohydrate complex, which is resolved similarly
to the hemicelluloses. Various intermediate terms of the hydrolytic series
have been isolated. But the only fully identified product of resolution is the
dextrose which finally results.

UEBER DIE KOHLENHYDRATE D. HEFE.

E. Salkowski (Berl. Ber., 27, 3325).

ON THE CARBOHYDRATES OF YEAST.

The author has isolated the more resistant constituents of the cell-membrane
by boiling with dilute alkalis, and exhaustively purifying with alcohol and
ether.
The residue was only a small percentage (3-4 p.ct) of the original, and
retained only 0.45 p.ct. N.
It was heated in a digester with water at 2-3 atm. steam-pressure, and thus
resolved into approximately equal portions of soluble cellulose (a) and
insoluble (b). The latter, giving no colour-reaction with iodine, is termed
achroocellulose; the former reacts, and is therefore termed erythrocellulose.
The former is easily separated from its opalescent solution. It has the
empirical composition of cellulose. In the soluble form it resembles
glycogen. The achroocellulose is isolated in the form of horny or
agglomerated masses. It appears to be resolved by ultimate hydrolysis into
dextrose and mannose.

SECTION V. FURFUROIDS, i.e. PENTOSANES
AND FURFURAL-YIELDING CONSTITUENTS
GENERALLY
(1) Reactions of the Carbohydrates with Hydrogen Peroxide.

C. F. Cross, E. J. Bevan, and Claud Smith (J. Chem. Soc., 1898, 463).

(2) Action of Hydrogen Peroxide on Carbohydrates in the
Presence of Ferrous Salts.

R. S. Morrell and J. M. Crofts (J. Chem. Soc., 1899, 786).

(3) Oxidation of Furfuraldehyde by Hydrogen Peroxide.

C. F. Cross, E. J. Bevan, and T. Heiberg (J. Ch. Soc., 1899, 747).

(4) EINWIRKUNG VON WASSERSTOFFHYPEROXID AUF
UNGESÄTTIGTE KOHLENWASSERSTOFFE.

C. F. Cross, E. J. Bevan, and T. Heiberg (Berl. Ber., 1900, 2015).

ACTION OF HYDROGEN PEROXIDE ON UNSATURATED
HYDROCARBONS.

The above series of researches grew out of the observations incidental to
the use of the peroxide on an oxidising agent in investigating the
hydrolysed furfuroids (102). Certain remarkable observations had
previously been made by H. J. H. Fenton (Ch. Soc. J., 1894, 899; 1895,
774; 1896, 546) on the oxidation of tartaric acid by the peroxide, acting in
presence of ferrous salts, the —CHOH—CHOH— residue losing H2 with

production of the unsaturated group,
—OH.C=C.OH—. These investigations have subsequently been
considerably developed and generalised by Fenton, but as the results have
no immediate bearing on our main subject we must refer readers to the J.
Chem. Soc., 1896-1900.
From the mode of action diagnosed by Fenton it was to be expected that the
CHOH groups of the carbohydrates would be oxidised to CO groups, and it
has been established by the above investigations (1) and (2) that the
particular group to be so affected in the hexoses is that contiguous to the
typical
|
—CO
group. There results, therefore, a dicarbonyl derivative ('osone'), which
reacts directly with 2 mol. phenyl hydrazine in the cold to form an osazone.
This was directly established for glucose, lævulose, galactose, and
arabinose (2). While this is the main result, the general study of the product
shows that the oxidation is not simple nor in direct quantitative relationship
to the H2O2 employed. The molecular proportion of the aldoses affected
appears to be in considerable excess, and the reaction is probably
complicated by interior rearrangement.
In the main, the original aldehydic group resists the oxidation. But a certain
proportion of acid products are formed, probably tartronic acid. On
distillation with condensing acids a large proportion of volatile monobasic
acids (chiefly formic) are obtained. The proportion of furfural obtained
amounts to 3-4 per cent. of the weight of the original carbohydrate.
Since the general result of these oxidations is the substitution of an OH
group for an H atom, it was of interest to determine the behaviour of
furfural with the peroxide. The oxidation was carried out in dilute aqueous
solution of the aldehyde at 20°-40°, using 2-3 mols. H2O2 per 1 mol.
C5H4O2. The main product is a hydroxyfurfural, which was separated as a
hydrazone. A small quantity of a monobasic acid was formed, which was
identified as a hydroxypyromucic acid. Both aldehyde and acid appear to be
the α β derivatives. The aldehyde gives very characteristic colour reactions

with phloroglucinol and resorcinol in presence of hydrochloric acid, which
so closely resemble those of the lignocelluloses that there is little doubt that
these particular reactions must be referred to the presence of the
hydroxyfurfural as a normal constituent.
The study of these oxidations was then extended to typical unsaturated
hydrocarbons—viz. acetylene and benzene. (4) From the former the main
product was acetic acid, but the attendant formation of traces of ethyl
alcohol indicates that the hydrogen of the peroxide may take a direct part in
this and other reactions. This view receives some support from the fact that
the interaction of the H2O2 with permanganates has now been established to
be an oxidation of the H2 of the peroxide by the permanganate oxidation,
with liberation, therefore, of the O2 of the peroxide as an unresolved
molecule [Baeyer].
Benzene itself is also powerfully attacked by the peroxide when shaken
with a dilute solution in presence of iron salts. The products are phenol and
pyrocatechol, with some quantity of an amorphous product probably
formed by condensation of a quinone with the phenolic products of
reaction.

These types of oxidation effects now established give a definite significance
to the physiological functions of the peroxide, which is a form of 'active
oxygen' of extremely wide distribution. It would have been difficult a priori
to devise an oxidant without sensible action on aldehydic groups, yet
delivering a powerful attack on hydrocarbon rings; or to have suggested a
synthesis of the sugars from tartaric acid with a powerful oxidising
treatment as the first and essential stage in the transformation.
Our present knowledge of such actions and effects suggests a number of
new clues to genetic relationships of carbon compounds within the plant.
The conclusion is certainly justified that the origin of the pentoses is
referable to oxidations of the hexoses, in which this form of 'active oxygen'
plays an important part.

We must note here the researches of O. Ruff, who has applied these
oxidations with important results in the systematic investigation of the
carbohydrates.

UEBER DIE VERWANDLUNG DER D-GLUCONSÄURE IN
D-ARABINOSE (Berl. Ber., 1898, 1573).

CONVERSION OF D-GLUCONIC ACID INTO D-
ARABINOSE.

D UND L ARABINOSE (Ibid. 1899, 550).

ZUR KENNTNISS DER OXYGLUCONSÄURE (Ibid. 1899,
2269).

ON OXYGLUCONIC ACID.

Ruff in these researches has realised a simple and direct transition from the
hexoses to the pentoses. By oxidising gluconic acid with the peroxide the β
—CHOH— group is converted into carbonyl at the same time that the
terminal COOH [α] is oxidised to CO2. The yields of the resulting pentose
are large. Simultaneously there is formed an oxygluconic acid, which
appears to be a ketonic acid of formula —CH2OH.CO.(CHOH)3.COOH—.

From these results we see a further range of physiological probabilities; and
with the concurrent actions of oxygen in the forms of or related to hydrogen
peroxide on the one side, and ozone on the other, we are able to account in a
simple way for the relationships of the 'furfuroid' group, which may include
a number of intermediate terms in the hexose-pentose series.

Following in this direction of development of the subject is a study of the
action of persulphuric acid upon furfural.

EINWIRKUNG DES CARO'SCHEN REAGENS AUF
FURFURAL.

C. F. Cross, E. J. Bevan, and J. F. Briggs (Berl. Ber., 1900, 3132).

Regarding this reagent as another form of 'active oxygen,' it is important to
contrast its actions with those of the hydrogen peroxide. Instead of the β-
hydroxyfurfural (ante, 115) we obtain the δ-aldehyde as the first product.
The aldehydic group is then oxidised, and as a result of attendant hydrolysis
the ring is broken down and succinic acid is formed, the original aldehydic
group of the furfural being split off in the form of formic acid. The
reactions take place at the ordinary temperature and with the dilute form of
the reagent described by Baeyer and Villiger (Ber. 32, 3625). These results
have some special features of interest. The α δ-hydroxyfurfural has similar
colour reactions to those of the α β-derivative, and may also therefore be
present as a constituent of the lignocelluloses. The tendency to attack in the
1·4 position in relation to an aldehydic group further widens the capabilities
of 'active oxygen' in the plant cell. Lastly, this is the simplest transition yet
disclosed from the succinyl to furfural grouping, being effected by a
regulated proportion of oxygen, and under conditions of reaction which
may be described as of the mildest. In regard to the wide-reaching functions
of asparagin in plant life, we have a new suggestion of genetic connections
with the furfuroids.

VERGLEICH DER PENTOSEN-
BESTIMMUNGSMETHODEN VERMITTELST
PHENYLHYDRAZIN UND PHLOROGLUCIN.

M. Krüger (Inaug.-Diss., Göttingen, 1895).

COMPARISON OF METHODS OF ESTIMATING
FURFURAL AS HYDRAZONE AND PHLOROGLUCIDE.

The author traces the development of processes of estimating furfural (1) by
precipitation with ammonia (furfuramide), (2) by volumetric estimation
with standardised phenylhydrazine, (3) by weighing the hydrazone.
In 1893 (Chem. Ztg. 17, 1745) Hotter described a method of quantitative
condensation with pyrogallol requiring a temperature of 100°-110° for two
hours. The insoluble product collected, washed, dried at 103°, and weighed,
gives a weight of 1.974 grm. per 1 grm. furfural.
Councler substitutes phloroglucinol for pyrogallol, with the advantage of
doing away with the digestion at high temperature. (Ibid. 18, 966.) This
process, requiring the presence of strong HCl, has the advantage of being
applied directly to the acid distillate, in which form furfural is obtained as a
product of condensation of pentoses, &c. A comparative investigation was
made, precipitating furfural (a) as hydrazone in presence of acetic acid, and
(b) as phloroglucide in presence of HCl (12 p.ct). In (a) by varying the
weights of known quantities of furfural, and using the factor, hydrazone ×
0.516 [+ 0.0104] in calculating from the weights of precipitates obtained,
the maximum variations from the theoretical number were +1.71 and -1.74.
In (b) it was found necessary to vary the factor from 0.52 to 0.55 in
calculating from phloroglucide to furfural. The greatest total range of
variation was found to be 2.5 p.ct. The phenol process is therefore equally
accurate, has the advantages above noted, and, in addition, is less liable to
error from the pressure in the distillates obtained from vegetable substances
of volatile products, e.g. ketonic compounds, accompanying the furfural.
This method has been criticised by Helbel and Zeisel [Sitz.-ber, Wiener
Akad. 1895, 104, ii. p. 335] on two grounds of error, viz. (1) the presence of
diresorcinol in all ordinary preparations of phloroglucinol, and (2) changes
in weight of the precipitate of phloroglucide on drying. The process was
carried out comparatively with ordinary preparations, and with specially
pure preparations of the phenol. The quantitative results were identical. The
criticisms in question are therefore dismissed. Although the process is to be
recommended for its simplicity and the satisfactory concordance of results
it is to be noted that it rests upon an empirical basis, since the phloroglucide
is not formed by the simple reaction 2 [C5H4O2 + C6H6O3] - H2O =
C22H18O9, but appears to have the composition C16H12O6.

In part ii. of this paper the author discusses the question of the probable
extent in the sense of diversity of constitution of furfural-yielding
constituents of plant-tissues. Glucoson was isolated from glucosazon, and
found to yield 2.9-3.6 p.ct. furfural. Gluconic acid distilled with
hydrochloric acid gave traces of furfural; so also with sulphuric acid and
manganic oxide.
Starch was oxidised with permanganate, and a mixture of products obtained
of which one gave a characteristic violet colouration with phloroglucol,
with an absorption-band at the D line. On distilling with HCl furfural was
obtained in some quantity. The product in question was found to be very
sensitive to the action of bases, and was destroyed by the incidental
operation of neutralising the mixture of oxidised products with calcium
carbonate. It was found impossible to isolate the compound.

UNTERSUCHUNGEN UEBER DIE
PENTOSANBESTIMMUNG MITTELST DER SALZSÄURE-
PHLORO-GLUCIN-METHODE.[8]

E. Kröber (Journ. f. Landwirthschaft, 1901, 357).

INVESTIGATION OF THE HYDROCHLORIC ACID-
PHLOROGLUCINOL METHOD OF DETERMINING
PENTOSANES.

This paper is the most complete investigation yet published of the now
well-known method of precipitating and estimating furfural in acid solution
by means of the trihydric phenol. In the last section of the paper is
contained the most important result, the proof that the insoluble
phloroglucide is formed according to the reaction
C5H4O2 + C6H6O3 - 2H2O = C11H6O3,

also, by varying the proportions of the pure reagents interacting, that the
condensation takes place invariably according to this equation.

Incidentally the following points were also established:—The solubility of
the phloroglucide, under the conditions of finally separating in a condition
for drying and weighing, is 1 mgr. per 100 c.c. of total solution, made up of
the original acid solution, in which the precipitation takes place, and the
wash-water required to purify from the acid. The phloroglucide is
hygroscopic, and must be weighed out of contact with the air. The presence
of diresorcinol is without influence on the result, provided a sufficient
excess of actual phloroglucinol is employed. Thus even with a preparation
containing 30 p.ct. of its weight of diresorcinol the influence of the latter is
eliminated, provided a weight be taken equal to twice that of the furfural to
be precipitated. The phenol must be perfectly dissolved by warming with
dilute HCl (1.06 sp.gr.) before adding to the furfural solution. For collecting
the precipitate of phloroglucide the author employs the Gooch crucible.
The paper contains a large number of quantitative results in proof of the
various points established, and concludes with elaborate tables, giving the
equivalents in the known pentoses and their anhydrides for any given
weight of phloroglucide from 0.050 to 0.300 grm.

UEBER DEN PENTOSAN-GEHALT VERSCHIEDENER
MATERIALIEN.

B. Tollens and H. Glaubitz (J. für Landwirthschaft, 1897, 97).

ON THE PENTOSANE CONSTITUENTS OF FODDER-
PLANTS AND MALT.

(p. 171) (a) The authors have re-determined the yield of furfural from a
large range of plant-products, using the phloroglucol method. The numbers
approximate closely to those obtained by the hydrazone method. The
following may be cited as typical:

Substance Furfural p.ct.
Rye (Göttingen) 6.03
Wheat (square head) 4.75
Barley (peacock) 4.33
Oats (Göttingen) 7.72
Maize (American) 3.17
Meadow hay 11.63
Bran (wheat) 13.06
Malt 6.07
Malt-sprouts 8.56
Sugar-beet (exhausted) 14.95

(b) A comparison of wheat with wheat bran, &c. was made by grinding in a
mortar and 'bolting' the flour through a fine silk sieve. The results showed:

Furfural p.ct.
Original wheat 4.75
Fine flour 1.73
Bran (24 p.ct. of wheat) 11.25
Wheat-bran of commerce 13.06

It is evident that the pentosanes of wheat are localised in the more resistant
tissues of the grain.
(c) An investigation of the products obtained in the analytical process for
'crude fibre' gave the following:
(1) In the case of brewers' grains:

100 grms. grains gave furfural = 29.43pentosane
———————
20 " crude fibre " = 2.52
Acid extract " = 22.76
Alkali " " = 1.20
Deficiency from total of original grains 2.95
———

29.43

(2) In the case of meadow hay:
The crude fibre (30 p.ct.) obtained retained about one fourth (23.63 p.ct.) of
the total original pentosanes.
(d) An investigation of barley-malt, malt-extract or wort, and finished beer
showed the following: An increase of furfuroids in the process of malting,
100 pts. barley with 7.97 of 'pentosane' yielding 82 of malt with 11.18 p.ct.
'pentosane'; confirming the observations of Cross and Bevan (Ber. 28,
2604). Of the total furfuroids of malt about 1/4 are dissolved in the mashing
process. In a fermentation for lager beer it was found that about /10 of the
total furfuroids of the malt finally survive in the beer; the yield of furfural
being 2.92 p.ct. of the 'total solids' of the beer. In a 'Schlempe' or 'pot ale,'
from a distillery using to 1 part malt 4 parts raw grain (rye), yield of
furfural was 9 p.ct. of the total solids.
In a general review of the relationships of this group of plant-products it is
pointed out that they are largely digested by animals, and probably have an
equal 'assimilation' value to starch. They resist alcoholic fermentation, and
must consequently be taken into account as constituents of beers and wines.

UEBER DAS VERHALTEN DER PENTOSANE DER SAMEN
BEIM KEIMEN.[9]

A. Schöne and B. Tollens (Jour. f. Landwirthschaft, 1901, 349).

BEHAVIOUR OF PENTOSANES OF SEEDS IN
GERMINATION.

The authors have investigated the germination of barley, wheat, and peas, in
absence of light, and generally with exclusion of assimilating activity, to
determine whether the oxidation with attendant loss of weight, which is the
main chemical feature of the germination proper, affects the pentosanes of
the seeds. The following are typical of the quantitative results obtained,
which are stated in absolute weights, and not percentages.

-- Original seed Malt or germinated product Pentosane in
A B A B
Barley 500.00 434.88 39.58 40.38
" 500.00 442.26 40.52 41.17
Peas 300.00 286.60 15.25 15.97

The authors conclude generally that there is a slight absolute increase in the
pentosanes, and that the pentosanes do not belong to those reserve materials
which undergo destructive oxidation during germination.
In this they confirm the previously published results of De Chalmot, Cross
and Bevan, and Gotze and Pfeiffer.

UEBER DEN GEHALT DER BAUMWOLLE AN
PENTOSAN.

H. Suringar and B. Tollens (Ztschr. angew. Chem., 1897, I).

PENTOSANE CONSTITUENTS OF COTTON.

(p. 290) It has been stated by Link and Voswinkel (Pharm. Centralhalle,
1893, 253), that raw cotton yields 'wood gum' as a product of hydrolysis.
The authors were unable to obtain any pentoses as products of acid
hydrolysis of raw cotton, and traces only of furfural-yielding carbohydrates.
They conclude that raw cotton contains no appreciable quantity of
pentosane.

FOOTNOTES:
[8] This paper appears during the printing of the author's original MS.
[9] This paper appears during the printing of the author's original MS.

SECTION VI. THE LIGNOCELLULOSES
(p. 131) Lignocellulose Esters.—By a fuller study of the ester reactions of
the normal celluloses we have been able to throw some light on the
constitutional problems involved; and we have extended the investigations
to the jute fibre as a type of the lignocelluloses, from the results of which
we get a clearer idea of the relationships of the constituent groups.
Taking the empirical expression for the complex, i.e. the entire
lignocellulose, the formula C12H18O9, we shall be able to compare the ester
derivatives with those of the celluloses, which we have also referred to a
C12 unit. But we shall require also to deal with the constituent groups of the
complex, which for the purposes of this discussion may be regarded as (a) a
cellulose of normal characteristics—cellulose α; (b) a cellulose yielding
furfural on boiling with condensing acids—cellulose β; and (c) a much
condensed, and in part benzenoid, group which we may continue to term
the lignone group.
The latter has been specially examined with regard to its proportion of OH
groups, as a necessary preliminary to the investigation of esters, in
producing which the entire complex is employed. It will be shown that the
ester groups can be actually localised in various ways, as in the main
entering the cellulose residues α and β. But that the lignone group takes
little part in the reactions may be generally concluded on the evidence of its
non-reactivity as an isolated derivative, (1) By chlorination, &c. it is
isolated in the form of an amorphous body, but of constant composition,
represented by the formula C19H18Cl4O9. This compound, soluble in acetic
anhydride, was boiled with it for six hours after adding fused sodium
acetate, and the product separated by pouring into water. The dilute acid
filtered from the product contained no hydrochloric acid nor by-products of
action. The product showed an increase of weight of 7.5 p.ct. For one acetyl
per 1 mol. C19H18Cl4O the calculated increase is 8.0 p.ct. It is evident from
the nature of the derivative that this result cannot be further verified by the
usual analytical methods. (2) The chlorinated derivative is entirely soluble

in sodium sulphite solution. This solution, shaken with benzoyl chloride,
with addition of sodium hydrate in successive portions, shows only a small
formation of insoluble benzoate, which separates as a tarry precipitate. (3)
The empirical formula of the lignone complex in its isolated forms indicates
that very little hydrolysis occurs in the processes of isolation. Thus the
chlorinated product we may assume to be derived from the complex
C19H22O9. In the soluble by-products from the bisulphite processes of
pulping wood the lignone exists as a sulphonated derivative,
C24H23(OCH3)2.(SO3H).O7. The original lignone may be regarded as
passing into solution as a still condensed complex derived from C24H26O12
(Tollens). There is evidently little attendant hydroxylation, and another
essential feature is the small molecular proportion of groups showing the
typical sulphonation.
It appears that in the lignone the elements are approximately in the relation
C6: H6: O3, and it may assist this discussion to formulate the main
constitutional types consistent with this ratio, viz.:
(1) The trihydroxybenzenes C6H3(OH)3.
(2) Methylhydroxyfurfural C5H2O.(OH)(CH3).
(3) Methylhydroxypyrone

(4) Trioxycyclohexane

It is probable that all these types of condensation are represented in the
lignone molecules, since the derivatives yielded in decompositions of more
or less regulated character are either directly derived from or related to such
groups. For the moment we pass over all but the general fact of complexity
and the marked paucity of OH-groups. It would be of importance to be able
to formulate the exact mode of union of the lignone with the cellulose

residues to constitute the lignocellulose. The evidence, however, does not
carry us farther than the probability of union by complicated groups and of
large dimensions; for not only is the lignone isolated in condensed and non-
hydroxylated forms, but the cellulose also is not hydrated or hydrolysed
further than in the ratio 3C6H10O5.H2O. It is probable, therefore, that the
water combining with the residues at the moment of their resolution is
relatively small.
Lastly, we have to remember, when dealing with the statistical results of the
reactions to be described, that the approximate proportions per cent. of the
constituent groups are:

Cellulose α 65}
" β 15} = 100 lignocellulose.
Lignone 20}

Jute Benzoates.—In preparing the jute for treatment it was boiled in
alkaline solution (1 per cent. NaOH), washed with water and dilute acid,
again washed, dried, and weighed.
In the ester reaction the reagents were employed in the proportion
C12H18O9: 3NaOH: 2C6H5COCl. A series of quantitative experiments gave
yields of 126-130 p.ct. of benzoate [calculated for monobenzoate 134 p.ct.].
The results were confirmed by ultimate analysis. The monobenzoate
therefore represents a maximum, and this molecular proportion is one-half
of that observed with the normal cellulose, calculated to the same unit.
Localisation of Benzoyl Group.—The entrance of the ester group affects the
typical colour reactions of the lignocellulose, which are fainter. The ferric
ferricyanide reaction almost disappears. The lignone group is unaffected,
and combines with chlorine as in the original. The lignone chloride is
removed by sodium sulphite solution, and the residue is a cellulose
benzoate. The loss of weight due to the elimination of the lignone was 12.7
p.ct. Calculating per 100 of the original lignocellulose this becomes 16.
These statistics further confirm the localisation of the benzoyl group in the
cellulose residue. It is to be noted that the presence of the benzoyl group
renders the cellulose more resistant to hydrolytic actions. Thus, to bring out

this fact more prominently, we may calculate the yield of residual cellulose
benzoate p.ct. of original jute, and we find it 109 p.ct. Taking a maximum
proportion for original cellulose—viz. 85—this benzoate represents a yield
of 129 p.ct., as against the theoretical for a monobenzoate, 132 p.ct.
Furfural Numbers.—The percentage of furfural obtained by boiling with
HCl of 1.06 sp.gr. was 3.02 and 3.29 in separate determinations. Calculating
to the original lignocellulose, the percentage, 4.21, indicates a considerable
loss of the furfural-yielding constituent. The effect was also apparent in the
cellulose (benzoate) isolated by chlorination &c., the percentage being 1.39
p.ct., and calculated to the original jute benzoate 1.59 p.ct. Under the
conditions adopted in dissolving away the chlorinated lignone the original
non-benzoated lignocellulose would have yielded a cellulose giving 6 to 7
p.ct. furfural.
Since the benzoyl group is hardly calculated to produce a constitutional
change affecting the furfural constants, it was necessary to examine the
effect of the preliminary alkaline treatment, and the change in the furfuroid
group was in fact localised in this reaction. It was found that, on washing
the alkali from the mercerised jute, and further purifying the residue, this
latter yielded only 4.2 p.ct. furfural [3.4 p.ct. on original fibre]. The alkaline
solution and washings were acidified and distilled from 10 p.ct. HCl,
yielding an additional 3.6 p.ct. calculated to the original lignocellulose. By
treatment with the concentrated alkali, therefore, the furfuroid of the
original lignocellulose undergoes little change, but is selectively dissolved.
This point is under further investigation.
(p. 132) Acetylation of Lignocelluloses.—Acetates are readily formed by
boiling the lignocelluloses with acetic anhydride. The derivatives obtained
from jute are only generally mentioned in the 1st edition (p. 132). A further
study of the reactions in regard to special points has led to some more
definite results. The yields of product by the ordinary and simple process
are 114-115 p.ct. But on analysing the product an important discrepancy is
revealed.
For the saponification we employ a solution of sodium ethylate in the cold.
The following numbers were obtained:

Acetic acid Hydrocellulose residue

27.2 77.8
Calc. for diacetate on C12H18O9 30.8 78.4

The derivative is approximately a diacetate, and on the assumption of a
simple ester reaction the yield should be 127 p.ct. Assuming that the
difference of 13 p.ct. is due to loss of water by internal condensation, it
appears that for each acetyl group entering, 2 mol. H2O are split off.

The jute acetate showed the normal reaction with chlorine, and the lignone
chloride was dissolved by treatment with sodium sulphite solution. The
fibrous residue was colourless. It proved to be a cellulose acetate. The
following numbers were obtained on saponification:

Acetic acid Cellulose
31.6 70.0
30.9 68.8
Calc. for diacetate on C12H20O10 29.4 79.9

The interpretation of these numbers appears to be this: in the original
reaction with the lignocellulose it is the cellulose residue which is
acetylated, and at the same time condensed. The cellulose residue which
undergoes condensation is not of the normal constitution, since the normal
cellulose is acetylated without condensation (see p. 41). On saponification a
portion of the cellulose, in again combining with water, is hydrolysed to
soluble products. The lignone group as it exists in the lignocellulose has no
free OH groups, and probably no free aldehydic groups such as would react
with the anhydride. Such groups may, however, be originally present, and
may take part in the internal condensations which have been shown to
occur. The furfural constants of the lignocellulose are unaffected by the
acetylation and condensation. The hygroscopic moisture of the product is
lowered from 10-11 p.ct. in the original to 4.5 p.ct. The ferric ferricyanide
reaction is inhibited by the disappearance of the reactive groups, upon
which this curious and characteristic phenomenon depends (1st ed.).
Acetylation of Benzoates.—The cellulose dibenzoate (C12 basis) and the
jute monobenzoate were acetylated under comparative conditions The
results were as follows:

C12 basis
Cellulose
Jute monobenzoate
dibenzoate
Calc. for Calc. for
diacetate diacetate
Found Found
on on
dibenzoate monobenzoate
Ester reaction
111 124
Yield 115 p.ct. 120 p.ct.
p.ct. p.ct.
Saponification{Cellulose}
53.5 52.6 59.8 61.9
{Lignocellulose}
NaOH
21.3 23.9 28.4 24.3
combining

From these results it would appear that the number of acetyl groups
entering the benzoates is the same as with the unbenzoylated fibres, the
benzoyl has no influence upon the hydroxyls as against the acetyl. At the
same time the internal condensation noticed in the acetylation of the jute
appears not to occur in the case of the benzoate.
Nitric Esters.—The numbers resulting from the quantitative study of the
ester reaction and product (1st ed. p. 133) show a very large divergence of
the yield of product from that which would be calculated from its
composition (N p.ct.) on the assumption that the ester reaction is simple. We
have repeated the results, and find with a yield of 145 p.ct. that the product
contains 11.8 p.ct. N.
The reaction
C12H18O9 + 4HNO3 - 4H2O

gives a tetranitrate with 11.5 p.ct. N and a yield of 159 p.ct. The ester
reaction, therefore, is not simple. There are two sources of the loss of
weight. The first of these is evident from the occurrence of certain
secondary reactions which result in the solution of a certain proportion of
the fibre substance in the acid mixture. To determine this quantitatively we

have devised a suitable variation of the method of combustion with chromic
acid (1st ed.).
The variation is required to meet the difficulty occasioned by the tension of
the nitric acid and products of deoxidation. The mixed acids (10 c.c.),
containing the organic by-products in solution, are carefully diluted in a
small flask with an equal volume of water, preventing rise of temperature.
Nitrous fumes are evolved during the dilution. Strong sulphuric acid (15
c.c.) is now added, and the residue of nitrous fumes expelled by a current of
air, agitating the contents of the flask from time to time. The combustion
with CrO3 is then proceeded with in the ordinary way. The gases evolved
are measured (total volume) and calculated to C present in the form of
products derived from the lignocellulose; and, assuming that this contains
47 p.ct. C, we may express the result approximately in terms of the fibre
substance. The method was controlled by blank experiments, in which citric
acid was taken as a convenient carbon compound for combustion. The C
found was 34.9 p.ct. as against 34.3 p.ct. calculated. By this method we find
that with maximum yields of nitrate at 143-145 p.ct. the organic matter in
solution in the acid mixture amounted to 4.9 to 5.3 p.ct. of the original
lignocellulose.
Introducing this quantity as a correction of the yield of nitrate in the original
reaction, we must express the 143 parts as obtained from 95 of fibre
substance instead of 100.
The yield per molecule C12H18O9 (= 306) is therefore 462, whereas for a
tetranitrate formed by a simple ester reaction the yield should be 486. The
difference (24) represents 1.5 mol. H2O split off by internal condensation.

The correction for total N is relatively small, raising it from 11.5 to 12.2,
which remains in close agreement with the experimental numbers.
Monobenzoate.—Treated with the acid mixture yields a mixed nitrate. The
yield is 130 p.ct., and the product contains 7.6 p.ct. O.NO2 nitrogen. These
numbers approximate to those required for reaction with 4HNO3 groups,
three of the residues entering the cellulose, and one (as NO2) the benzene
ring of the substituting group. For such a reaction the calculated numbers
are: Yield 144 p.ct.; O.NO2 nitrogen 7.1 p.ct.

The experimental numbers require correcting for the amount of loss in the
form of products soluble in the acid mixture, viz. 7.6 p.ct.; but they remain
within the range of the experimental errors sufficiently to show that the
benzoyl group limits the number of OH groups taking part in the ester
reaction to three. The corrected yield per 1 mol. of jute benzoate (410) is
576, as against the calculated 590 for 4HNO3 reacting. A loss of 1H2O per
molecule by internal condensation is therefore indicated.
Denitration.—The removal of the nitric groups from the esters is effected
by digestion with ammonium sulphide. But the reactions are by no means
simple. There is considerable hydrolysis of the lignocellulose to soluble
products. Thus the tetranitrate yields only 46.4 of denitrated fibre in place
of the calculated 66. The product is a cellulose, yielding only 0.5 per cent.
furfural. The hydrolysed by-products, moreover, when freed from sulphur
and distilled from hydrochloric acid, yielded only an additional 2.5 p.ct.
furfural, calculated to the original lignocellulose.
These statistics confirm the evidence that the ester reaction is not simple.
Such changes take place in the lignone-β-cellulose complex that they revert,
not to their original form, but to soluble derivatives of different constitution.
The mixed nitrate from the benzoate is denitrated to a cellulose
amidobenzoate, which confirms the localisation of a nitro-group in the
benzoyl residue.
(p. 157) General Characteristics of the Lignocelluloses.—Later
investigations have somewhat modified and simplified our views of the
constitution of the typical lignocellulose (jute), so far as this can be dealt
with by the statistics of its more important decompositions (original, pp.
157-161).
Cellulose.—There is little doubt that the furfural-yielding groups of the
original are isolated in the form of the β-cellulose. Tollens emphasises this
fact in his studies of cellulose-estimation methods. We had previously
shown (original, p. 159) that the yield of furfural is not affected by the
chlorination, but it appears from our numbers that only 50 p.ct. of these
groups remain in the isolated cellulose, the residue undergoing hydrolysis to
soluble compounds. In a carefully regulated hydrolysis following the

chlorination it appears that the furfuroids are almost entirely conserved in
the form of a cellulose.
Moreover, an investigation of the products dissolved by sodium sulphite
solution from the chlorinated fibre has shown that they are practically free
from furfuroids. This enables us to exclude the furfural-yielding groups
from the lignone complex. At the same time, through our later studies of the
hydroxyfurfurals, it is certain that these products are represented in the fibre
substance and probably in the lignone complex.
Chlorination Statistics.—It has been pointed out by a correspondent—to
whom we express our indebtedness—that we have made a mistake in
calculating the proportion of lignone from the ratio of the Cl combining
with the fibre substance or lignocellulose (p.ct), to that of the Cl present in
the isolated lignone chloride (p.ct.). The lignocellulose combines with
chlorine in the ratio 100: 8, but the lignone chloride containing 26.7 of
chlorine means that, neglecting the hydrogen substituted, 73 of lignone
combine with the 27 of chlorine approximately. On the uniform percentage
basis the calculated proportion of lignone would be 8/37, or a little over 20
p.ct.
In regard to the proportion of hydration attending the resolution, we have
shown on constitutional grounds that this must be relatively small.
Assuming approximately the formula C19H22O9 for the lignone residue as it
exists in combination, and the anhydride formula for the cellulose, these
revised statistics now appear, as regards the carbon contents of the
lignocellulose:

Cellulose, 44.4 C; lignone, 57.8.
80 × 44.4 ÷ 100 = 35.52
20 × 57.8 ÷ 100 = 11.56
_____
47.08 p.ct. C in lignocellulose.

These conclusions are in accordance with the experimental facts, and, taken
together with the new evidence we have accumulated from a study of the
lignocellulose esters, we may sum up the constitutional points as follows:
The lignocellulose is a complex of

Cellulose α Cellulose β Lignone
65 p.ct. 15 p.ct. 20
Allied to the normal Yielding furfural One-third of which is of
celluloses approximately 50 p.ct. benzenoid type

The lignone contains but little hydroxyl. The celluloses are in condensed
hydroxyl union with the lignone, but the combination occurs by complexes
of relatively large molecular weight.

DIE CHEMIE DER LIGNOCELLULOSEN—EIN NEUER
TYPUS.

W. C. Hancock and O. W. Dahl (Berl. Ber., 1895, 1558).

Chemistry of Lignocelluloses—A New Type.

The stem of the aquatic Æschynomene aspera offers an exceptional instance
of structural modification to serve the special function of a 'float,' 1 grm. of
substance occupying an apparent volume of 40-50 c.c. This pith-like
substance is morphologically a true wood (De Bary), and the author's
investigations now establish that it is in all fundamental points of chemical
composition a lignocellulose, although from its colour reactions it has been
considered by botanists to be a cellulose tissue containing a proportion of
lignified cells. Thus the main tissue is stained blue by iodine in presence of
hydriodic acid (1.5 s.g.), and the colour is not changed on washing. The
ordinary lignocelluloses are stained a purple brown changed to brown on
washing. The reactions with phloroglucol and with aniline salts,
characteristic of these compounds, is only faintly marked in the main tissue,
though strongly in certain individual cells.
The following quantitative determinations, however, establish the close
similarity of the product to the typical lignocelluloses:
Elementary Analysis.—C 46.55, H 6.7. Furfural 11.6 p.ct., of which there
remained in the residue from alkaline hydrolysis (71 p.ct.) 8.0, i.e. about 70

p.ct. The distribution of the furfuroids is therefore not affected by the
alkaline treatment.
Chlorination.—The substance (after alkaline hydrolysis) takes up 16.9 p.ct.
Cl, of which approximately one-half is converted into hydrochloric acid.
Methoxyl.—O.CH3 estimated = 2.9 p.ct.

Ferric Ferricyanide Reaction.—Increase of weight due to blue cyanide
fixed (1) 75 p.ct., (2) 96 p.ct. Ratio, Fe: CN = 1: 2, 4.
Hydroxyl Reactions.—In the formation of nitric esters and in the
sulphocarbonate reaction the substance gave results similar to those
obtaining for the jute fibre.
These results establish the general identity of this peculiar product of plant
life with the lignocelluloses, at the same time that they show that certain of
the colour reactions supposed to characterise the lignocelluloses are due to
by-products which may or may not be present.
(p. 172) Composition of Elder Pith.—In a systematic investigation of the
celluloses in relation to function we shall have to give special attention to
the parenchymatous tissues of all kinds. These are, for structural reasons,
not easily isolated, for which reason and their generally 'inferior' functions
they do not present themselves to chemical observation in the same obvious
way as do their fibrous relatives. The pith of the elder, however, is readily
obtained in convenient masses, and a preliminary investigation of the entire
tissue has established the following points:
The reactions of the tissue are in all respects those of the lignocelluloses.
Composition.—Ash, 2.2 p.ct.; moisture in air-dry state, 12.3 p.ct. Alkaline
hydrolysis (loss): (a) 14.77, (b) 17.84. Cellulose (yield), 52.33 p.ct. Nitrate-
reaction complicated by secondary reactions and yields low, 90.95 p.ct.
Sulphocarbonate reaction: Resists the treatment, less than 10 p.ct. passes
into solution.
Furfural.—The original tissue yields 7.13 p.ct.; the residue from alkaline
hydrolysis (b) 5.40 p.ct.

This tissue is, therefore, a lignocellulose having the chemical characteristics
typical of the group, but of less resistance to hydrolytic actions.
The investigation will be prosecuted in reference to the cause of
differentiation in this latter respect. Probably the pectocelluloses are
represented in the tissue.

The Insoluble Carbohydrates of Wheat (grain).

H. C. Sherman (J. Amer. Chem. Soc., 1897, 291).

(p. 171) This is a study of the constituents of the cell-walls of wheat grain.
Bran was taken as the most convenient form of the raw material, being
freed from starch by treatment with malt extract, and further treated (1) with
cold dilute ammonia, (2) cold dilute soda lye (2 p.ct. NaOH), and (3)
boiling 0.1 p.ct. NaOH. The product retained only 1.25 p.ct. proteids, and
yielded 15.62 p.ct. furfural.
Acid Hydrolysis.—The product was boiled 30 mins. with dilute acid (1.25
p.ct. H2SO4), and the solution boiled until the Fehling test showed no
further increase of monoses. At the limit the reducing power of the
dissolved carbohydrates was 91.3 p.ct., that of dextrose. Converted into
osazones the analysis showed them to be pure pentosazones. The
hemicellulose of wheat is, therefore, according to the author, pure
pentosane.
Residue.—This was a lignocellulose yielding 11.5 p.ct. furfural. It was
subjected to a series of treatments with ferric ferricyanide, and the
proportion of Prussian blue fixed was determined by increase of weight,
viz. from 10 p.ct. to 47 p.ct. according to the conditions. The results
confirmed those of Cross and Bevan first obtained with the typical
lignocellulose (jute).
Chlorination.-The residue was boiled with dilute alkali, washed, and
exposed to chlorine gas. The resulting lignone chloride was isolated by
solution in alcohol, &c. It yielded 26.7 p.ct. Cl on analysis. In this and its
properties it appeared to be identical with the product isolated by Cross and
Bevan from jute, with the empirical formula C19H18Cl4O9.

Cellulose was isolated from the residue by three of the well-known
methods, and the following comparative numbers are noteworthy:

F. Schulze Lange Cross and
Method Dil. HNO3 Fusion Bevan
KClO3 KOH Chlorine, &c.
Cellulose p.ct. obtained 66.0 39.3-43.1 66.5
Furfural p.ct. of cellulose 7.0 3.96 5.62
Residual nitrogen 0.22 0.03 0.00
Ferricyanide reaction, Prussian
6.04 0.89 0.92
blue fixed

The author remarks: 'It is evident no one feature can be urged as a criterion
in judging between the methods, but all must be taken into consideration.
Such a comparison shows the superiority of the chlorination method.'
The cellulose is not of the normal (cotton) type, since on treatment with
sulphuric acid it dissolves with considerable discolouration, but only to the
extent of about 80 per cent. The dissolved monoses converted into osazones
were found to consist of hexoses only. The cellulose treated with caustic
soda solution (5 p.ct. NaOH) in the cold yielded 20 p.ct. of its weight of
soluble constituents, but as the residue yielded 3.34 p.ct. furfural the attack
of the alkali is by no means confined to the furfuroids.
Animal Digestion of the Constituents of Bran.—Observations on a steer
fed upon wheat bran only established the following percentage digestion of
the several constituents:

Soluble carbohydrates 96.9
Starch 100.0
Free pentosanes 60.2
Cellulose 24.8
Lignin complex 36.7
Proteid 82.96
Ether extract 42.73
_____________________ ______
Nitrogen-free extract 76.08

Crude fibre 32.21

JOURNAL OF THE IMPERIAL INSTITUTE

(Research Department, Vols. 1-2, 1895-6).

(p. 109) In this journal appear a series of notices of the results of analyses
of vegetable fibres by the method described in 'Report on Miscellaneous
Fibres' (Col. Ind. Exhibition Reports, p. 368) [C. F. Cross]. These
investigations deal with the following subjects:
1895. p. 29 Various Indian Fibres—more particularly Sida.
(a) 118 (a) Fibres from Victoria; (b) SpecialAnalyses ofSamples of Jute; (c)
Paper-making Fibres from S. Australia.
202 Fibres from Victoria.
287 Fibres from Victoria.
366 Sisal from Trinidad.
373 Rope-fibres from Grenada.
(b) 398 Report of Experiments on Indian Jute (1).
435} Fifth and Sixth Report on Australian Fibres.
473}
1896. 68 Hibiscus and Abroma Fibres.
104-5 Hibiscus, Urena, and Crotalaria Fibres.
141 Indian Sisal
(c) 182-3 Report of Experiments on Indian Jute (2).
264 Sanseviera from Assam.
From the above we may draw the general conclusion that the scheme of
investigation has been found in practice to answer its main purpose, viz. to
afford such numerical constants as determine industrial values. In
illustration we may cite (a) the results of analyses of specially selected
samples of jute, from which it will be seen that there is a close concordance
of value as ordinarily determined from external appearance, with the
chemical constants as determined in the laboratory.

Quality of Jute
Low Medium Extra Extra Fine

Moisture 11.0 10.4 11.1 9.6
Ash 0.87 2.8 1.0 0.7
Alkaline hydrolysis (a) 5 mins. boiling 13.2 11.6 8.5 9.1
Alkaline hydrolysis (b) 60 mins. boiling 16.1 17.5 12.5 13.1
Mercerising treatment 9.2 10.5 10.3 8.5
Nitration (increase p.ct.) 36.6 35.7 37.5 36.7
Cellulose (yield) 71.4 70.0 79.0 77.7
Acid purification 2.6 1.3 1.9 2.0

A useful series of experiments, initiated by the Institute, is that noted under
(b) and (c) above.
(1) To ascertain the quality of the fibre extracted from the plant at different
stages of growth, quantities of 400 lbs. of the stalks were cut at successive
stages and the fibre isolated after steeping 14-20 days. The fibre was
shipped to England and chemically investigated, with the following results:

No. 1. Cut before appearance of inflorescence.
" 2. " after budding.
" 3. " in flower.
" 4. " after appearance of seed-pod.
" 5. " when fully matured.
(1) (2) (3) (4) (5)
Moisture 11.55 8.7410.710.09.72
Ash 1.1 1.1 1.1 1.1 0.90
Alkaline hydrolysis (a) 6.2 8.5 9.7 8.9 7.3
" " (b) 10.5 11.9 11.6 12.0 11.2
Mercerising treatment 10.2 10.712.0 8.1 11.0
Nitration 37.2 32.132.233.236.6
Cellulose 74.0 76.274.174.876.4
Acid purification 0.8 0.5 0.7 2.4 1.4

It will be thus seen that there are no changes of any essential kind in the
chemical composition of the bast fibre throughout the life-history of the
plant, confirming the conclusion that the 'incrustation' view of lignification
is consistent only with the structural features of the changes, and so far as it

has assumed the gradual overlaying of a cellulose fibre with the lignone
substance it is not in accordance with the facts.
Examination of the samples from the point of view of textile quality
showed a superiority of No. 1 in fineness, softness, and strength; from this
stage there is observed a progressive deterioration, but the No. 4 sample
(which was taken at the usual period of cutting) is superior to No. 5.
In a further series of experiments (c) the jute was subjected to certain
chemical treatments immediately after the separation of the fibre from the
plant. These consisted in steeping (1) in solution of sodium carbonate, as
well as of plant ashes, and (2) in sulphite of soda, the purpose of the
treatments being to modify or arrest the changes which take place in the
fibre when press-packed in bales for shipment. The samples were shipped
from India under the usual conditions and examined soon after arrival. It
was found that the chemical treatments had produced but small changes in
chemical composition of the fibre-substance. The sulphite treatment was the
more marked in influence, somewhat lowering the cellulose and nitration
constants. The conclusion drawn from the results was that they afford no
prospect of any useful modification, i.e. improvement of the textile quality
of the fibre by any chemical treatments such as could be applied to the fibre
on the spot before drying for press-packing and shipment.
The other matters investigated in the Institute laboratory and reported on as
indicated above are rather of commercial significance, and contributed no
points of moment to the chemistry of cellulose.

OBSERVATIONS ON SOME OF THE CHEMICAL
SUBSTANCES IN THE TRUNKS OF TREES.

F. H. Storer (Bull. Bussey Inst., 1897, 386).

(p. 172) An examination of the outer and inner wood and of the bark of the
grey birch, at different seasons of the year, gave the following yields of
furfural p.ct. on the dry substance:

Wood Bark

Inner Outer
May 21.3 19.6 16.7
July 16.6 18.8 11.4
October 16.2 16.3 12.3

The paper contains the results of treating the woods and various vegetable
products with hydrolysing agents in order of intensity: (a) Malt-extract at
60°C., (b) boiling dilute HCl (1.0 p.ct. HCl), and (c) boiling dilute HCl (2.5
p.ct.). The residues were found to yield considerable proportions of furfural.
The following numbers are typical:

Birch Stones of
Bark Wood Date Apricot Peach
Action of malt extract calculated as
4.24 3.5 5.2 1.5 —
starch dissolved
Mannan
Residue boiled, 1 p.ct. HCl gave
— — 11.7 14.1 6.7
pentosanes dissolved.
Residue yielded furfural 19.3 17.8 3.4 9.6 9.7

The proportion of pentosanes (furfuroids) removed, i.e. hydrolysed by
boiling with hydrochloric acid of 2.5 p.ct. HCl, is shown by the following
estimations of furfural:

Birch Sugar maple
Apricot
Outer Inner
Bark Wood stones
wood wood
In original substance 16.7 19.6 18.2 20.7 18.4
In residue from action of 2.5
6.53 8.6 4.9 6.4 7.0
p.ct. HCl

Wood Gum.—The paper contains some observations on the various methods
of isolating this product. Attention is directed to the necessary impurity of
the product, and to the fact that the numbers for furfural and for the xylose
yielded by hydrolysis are considerably less than for a pure pentosane.

Estimation of Cellulose.—The author investigated the process of Lange and
the 'celluloses' obtained from various raw materials. The products from the
woods of birch and maple contained furfural-yielding constituents,
represented by yields of 6-8 p.ct. furfural. Preference is given to the process
by comparison with others, at the same time that it is recommended in all
cases to examine the product for furfural quantitatively, converting the
numbers into pentosane equivalents, and subtracting from the total
'cellulose' to give the true cellulose.

ZUR KENNTNISS DER MUTTERSUBSTANZEN DES
HOLZGUMMI.

E. Winterstein (Ztschr. Physiol. Chem., 1892, 381).

ON THE MOTHER SUBSTANCES OF WOOD-GUM.

(p. 188) According to the text-books beech-wood may be regarded as the
typical raw material for the preparation of the laboratory product known as
wood-gum. The author has subjected beech-wood and beech-wood
cellulose (Schulze process) to a range of hydrolytic treatments, acid and
alkaline, in order to determine the conditions of selective action upon the
mother substance of the wood-gum. In the main it appears that this group of
furfuroids is equally resistant with the cellulose constituents of the wood; in
fact, that the mother substance of wood-gum is a modified cellulose, and
exists in the wood in chemical combination with the 'incrusting substances.'
Of the author's experimental results the following may be cited as typical:

Substance Yield of furfural p.ct.
Original beech-wood 13.8
After boiling 3 hrs. with 1.25 p.ct. H2SO4 (residue) 10.1
" " " " 5.0 " " " 5.6

Cellulose—isolated by Schulze process (yield 53 p.ct.) 6.9
after further 14 days' digestion with the Schulze acid (HNO3
" 5.9
+ KClO3)

" after extraction with 5 p.ct. NaOH in cold (residue) 5.0
" after second extraction with 5 p.ct. NaOH in cold (residue) 4.4

UEBER DIE FRAGE NACH DEM URSPRUNG
UNGESÄTTIGER VERBINDUNGEN IN DER PFLANZE.

C. F. Cross, E. J. Bevan, and C. Smith (Berl. Ber., 1895, 1940).

ON THE SOURCE OF THE UNSATURATED COMPOUNDS
OF THE PLANT.

(p. 179) In distilling for furfural by the usual methods of boiling cellulosic
products with condensing acids, the furfural is accompanied by volatile
acids, also products of decomposition of the cellulosic complex. A series of
distillations was carried out with dilute sulphuric acids of varying
concentration from 10-50 H2SO4: 90-50 H2O by weight, using barley straw
as a typical cellulosic material. The distillates were collected in successive
fractions, and the furfural and volatile acid determined. The results are
given in the form of curves. The aggregate yields were as follows:—

Concentration of acid (H2SO4) p.ct. 10 15 20 30 40 50
Furfural yield p.ct. of straw 2.0 2.0 4.410.1 11.5 11.0
Volatile acid (calculated as acetic acid) p.ct. of
1.7 1.9 3.14.3 6.3 14.8
straw

With acids up to 20 p.ct. H2SO4 both products are formed concurrently and
in nearly equal quantity. With the 30 p.ct. acid there is a great increase in
the total furfural, and with the 40 p.ct. acid it reaches nearly the maximum
obtainable with HCl of 1.06 s.g. (Tollens), in this case 12.4 p.ct. The
volatile acid increases, but in less ratio; it is also produced concurrently.
With 50 p.ct. H2SO4 the conditions are changed. The total furfural is rapidly
formed, whereas the volatile acid continues to be formed long after the
aldehyde ceases to come over. Moreover, whereas in the previous cases it
was mainly acetic acid, it is now mainly formic acid. The method was then

extended to a typical series of celluloses, heated with the more concentrated
acid (40-50 p.ct. H2SO4), with the following results:

— — Volatile acid
AceticFormic
Swedish filter-paper 0.3 2.7 17.2
Esparto cellulose 12.4 3.2 16.6
Bleached cotton trace 3.1 13.2
Raw cotton (American) — 5.0 9.4
Jute cellulose 5.2 4.9 22.7
Beech (wood) cellulose 6.4 3.5 14.6

The tendency in the hexoses and their polyanhydrides to split off one
carbon atom in the oxidised form, throws some light on the furfurane type
of condensation, which is represented in the lignocelluloses. We are still
without any evidence as to the possible transition of the hexoses to
benzenoid compounds. Such transitions would be more easily explained on
the assumption that the celluloses are composed in part of polyanhydrides
of the ketoses.

SPIRITUS AUS CELLULOSE UND HOLZ.

E. Simonsen (Ztschr. angew. Chem., 1898, 3).

PRODUCTION OF ALCOHOL FROM CELLULOSE AND
WOOD.

(pp. 50, 209) This investigation was undertaken with one main object—to
determine the optimum conditions of treatment of wood-cellulose and of
wood itself for conversion into 'fermentable sugar.' The process of
'inversion' or hydrolysis, by digestion with dilute acid at high temperature,
involves the four main factors: pressure (i.e. temperature), concentration of
acid, ratio of liquid to cellulose and duration of digestion. Each of these was
varied in definite gradations, and the effect measured. The degree of action
was measured in terms of 'reducing sugar,' calculated from the results of

estimation by Fehling solution, as 'glucose' per cent. of original cellulose
(or wood).
(a) Cellulose. [Wood-cellulose obtained by bisulphite process.]—With a
proportion of total liquid to cellulose of 27:1, and using sulphuric acid as
the hydrolysing agent, the optimum results were obtained with acids of
0.45-0.60 p.ct. (H2SO4) and pressures of 6-8 atm. The maximum yield of
'sugar' was 45 p.ct. of the cellulose.
Under the above conditions the maximum of conversion is attained in 2
hours.
Having now regard to the production of a solution of maximum
concentration of dissolved solids, the following conditions were asertained
to fulfil the requirement, and, in fact, may be regarded as the economic
optimum:

Proportion of total liquid 6 times wt. of cellulose
Concentration of acid 0.5 p.ct. H2SO4
Pressure 10 atm.
Duration of digestion 1.5 hour

giving a yield of 41 p.ct. 'reducing sugar' calculated to the original cellulose
(dry).
Alcoholic Fermentation of Neutralised Extract.—The liquors were found to
ferment freely, and on distillation to yield a quantity of alcohol equal to 70
p.ct. of the theoretical—i.e. on the basis of the numbers for copper oxide
reduction.
(b) Hydrolytic 'Conversion' of Wood (Lignocellulose).—A similarly
systematic investigation carried out upon pine sawdust established the
following as optimum conditions:

Proportion of total liquid 5 times wt. of wood
Concentration of acid 0.5 p.ct. H2SO4
Pressure 9 atm.
Duration of digestion 15 minutes

giving a yield of 20 p.ct. 'reducing sugar,' calculated from the 'Fehling' test.
Fermentation of the neutralised extracts gave variable results. The highest
yields obtained were 60 p.ct. of theoretical, the author finally concluding
that under properly controlled conditions of inversion and fermentation 100
kg. wood yield 6.5 l. absolute alcohol.

ÜBER DIE URSACHE DER VON SIMONSEN
BEOBACHTETEN UNVOLLSTÄNDIGKEIT DER
VERGÄHRUNG DER AUS HOLZ BEREITETEN
ZUCKERFLÜSSIGKEITEN.

B. Tollens (Ztschr. angew. Chem., 1898, 15).

ON THE CAUSE OF INCOMPLETE FERMENTATION OF
SUGARS OBTAINED BY ACID HYDROLYSIS OF WOOD.

The author criticises Simonsen's explanation of the results obtained with
extracts from pine wood. The incompleteness of fermentation of the
products is certainly due in part to the presence of furfural-yielding
carbohydrates, which are resistant to yeast. The pine woods contain 8-10
p.ct. of these constituents in their anhydride form ('pentosanes'). They yield
readily to acid hydrolysis, and certainly constitute a considerable
percentage of the dissolved products. A similar complex was obtained by
the author in his investigation of peat (Berl. Ber. 30, 2571), and was found
to be similarly incompletely attacked by yeast. The yields of alcohol
corresponded with the proportion of the total carbohydrates disappearing.
These were the hexose constituents of the hydrolysed complex, the pentoses
(or 'furfuroids') surviving intact.

UEBER SULFITCELLULOSEABLAUGE.

H. Seidel (Ztschr. angew. Chem., 1900).

WASTE LIQUORS FROM BISULPHITE PROCESS.

(p. 210) Later researches confirm the conclusion that in the soluble by-
products of these cellulose processes the S is combined as a SO3H group.
The following analyses of the isolated lignin sulphonic acid are cited:

C H S
(a) Lindsey and Tollens 56.125.30 5.65
(b) Seidel (1) 56.275.87 5.52
(c) Seidel and Hanak (2) 53.695.22 8.80
(d) Street 50.225.64 7.67

The variations are due to the varying conditions of the digestion of the
wood and to corresponding degrees of sulphonation of the original lignone
group. Calculating the composition of the latter from the above numbers on
the assumption that the S represents SO3H, the following figures result:

(a) and (b) (c) (d)
C 64.00 65.159.61
H 6.65 6.336.69

This author considers that beyond the empirical facts established by the
above named[10] very little is yet known in regard to the constitution of the
lignone complex.
Nor is there any satisfactory application of this by-product as yet evolved.
Evaporation and combustion involve large losses of sulphur [D.R.P. 74,030,
83,438; Seidel and Hanak, Mitt. Techn. Gew. Mus. 1898]. A more complete
regeneration of the sulphur has been the subject of a series of patents
[D.R.P. 40,308, 69,892, 71,942, 78,306, 81,338], but the processes are
inefficient through neglect of the actual state of combination of the S, viz.
as an organic sulphonate. The process of V.B. Drewson (D.R.P. 67,889)
consists in heating with lime under pressure, yielding calcium monosulphite
(with sulphate and the lignone complex in insoluble form). The sulphite is
redissolved as bisulphite by treatment with sulphurous acid. This process is
relatively costly, and yields necessarily an impure lye. It has been proposed
to employ the product as a foodstuff both in its original form and in the
form of benzoate (D.R.P. 97,935); but its unsuitability is obvious from its
composition. A method of destructive distillation has been patented (D.R.P.

45,951). The author has investigated the process, and finds that the yield of
useful products is much too low for its economical development. Fusion
with alkaline hydrates for the production of oxalic acid (D.R.P. 52,491) is
also excluded by the low yield of the product.
The application of the liquor for tanning purposes (D.R.P. 72,161) appears
promising from the fact that 28 p.ct. of the dry residue is removed by
digestion with hide powder. This application has been extensively
investigated, but without practical success. Various probable uses are
suggested by the viscosity of the evaporated extract. As a substitute for glue
in joinery work, bookbinding, &c., it has proved of little value. It is applied
to some extent as a binding material in the manufacture of briquettes, also
as a substitute for gelatin in the petroleum industry. Cross and Bevan (E.P.
1548/1883) and Mitscherlich (D.R.P. 93,944 and 93,945) precipitate a
compound of the lignone complex and gelatin by adding a solution of the
latter to the liquors. The compound is redissolved in weak alkaline solutions
and employed in this form for engine-sizing papers. Ekman has patented a
process (D.R.P. 81,643) for 'salting out' the lignone sulphonates, the product
being resoluble in water and the solution having some of the properties of a
solution of dextrin. Owing to its active chemical properties this product
—'dextron'—has a limited capability of substituting dextrin. The suggestion
to employ the evaporated extract as a reducing agent in indigo dyeing and
printing has also proved unfruitful. The author's application of the soda salt
of the lignone sulphonic acid as a reducing agent in chrome-mordanting
wool and woollen goods (D.R.P. 99,682) is more successful in practice, and
its industrial development shows satisfactory progress. The product is
known as 'lignorosin.'

FOOTNOTES:
[10] See more particularly: Lindsey and Tollens, Annalen, 267, 341; Cross and
Bevan's Cellulose, pp. 197-203; Street, Inaug.-Diss., Göttingen, 1892; Klason,
Rep. d. Chem. Ztg. 1897, 261; Seidel and Hanak, Mitt. d. Techn. Gew. Mus.
1897-1898.

SECTION VII. PECTIC GROUP
UNTERSUCHUNGEN ÜBER PECTINSTOFFE.

R. W. Tromp de Haas and B. Tollens (Lieb. Ann., 286, 278).

ÜBER DIE CONSTITUTION DER PECTINSTOFFE, B.
Tollens (ibid. 292).

INVESTIGATIONS OF PECTINS.

(p. 216) It is generally held that the pectins are, or contain, oxidised
derivatives of the carbohydrates. The authors have isolated and analysed a
series of these products, and the results fail to confirm a high ratio O : H.
The following are the analytical numbers:

Pectin from Ash C H Ratio H : O
Apple 6.2 43.46.4 1 : 7.9
Cherry 20.542.56.5 1 : 7.9
Rhubarb 4.2 43.36.8 1 : 7.4
Currant 5.0 47.15.9 1 : 8.5
Greengage 3.3 43.05.9 1 : 8.5
Turnip 7.3 41.05.9 1 : 9.0

Acid hydrolysis (4 p.ct. H2SO4) gave syrupy products not crystallisable—in
certain cases the hydrolysis was accompanied by separation of insoluble
cellulose. The insoluble product from currant pectin had the composition C
54.4, H 5.0.
Tollens points out that the results of empirical analysis are inconclusive;
and that from the acid reactions of these products and their combination
with bases, carboxylic groups are present, though probably in anhydride or
ester form.

The pectins may be regarded as closely related to the mucilages
(Pflanzenschleim), differing from them only by the presence of the oxidised
groups in question.

UEBER DIE CONSTITUTION DER PECTINSTOFFE.

C. F. Cross (Berl. Ber., 1895, 2609).

CONSTITUTION OF PECTINS.

It is pointed out that the composition of the pectin of white currants, as
given in the preceding paper, is that of the typical lignocellulose, the jute
fibre. The product was isolated and further investigated by the author. It
gave 9.8 p.ct. furfural on boiling with HCl (1.06 s.g.), reacted freely with
chlorine, giving quinone chlorides, and with ferric ferricyanide to form
Prussian blue. This 'pectin' is therefore a form of soluble lignocellulose. The
'pectic' group consequently must be extended to include hydrated and
soluble forms of the mixed complex of condensed and unsaturated groups
with normal carbohydrates, such as constitute the fibrous lignocelluloses.

UEBER DAS PFLANZLICHE AMYLOID.

E. Winterstein (Ztschr. Physiol. Chem., 1892, 353).

ON VEGETABLE AMYLOID.

(p. 224) A group of constituents of many seeds, distinguished by giving
slimy or ropy 'solutions' under the action of boiling water are designated
'amyloid.' They are reserve materials, and in this, as in the physical
properties of their 'solutions,' they are very similar to starch. They are,
however, not affected by diastase; and generally are more resistant to
hydrolysis. Typical amyloids have been isolated by the author from seeds of
Tropœolum majus, Pœonia officinalis, and Impatiens Balsamina. The raw
material was carefully purified by exhaustive treatment with ether and
alcohol, &c.; the amyloid then extracted by boiling with water, and isolated
by precipitation with alcohol. Elementary analysis gave the numbers C

43.2, H 6.1. On boiling with 12 p.ct. HCl it gave 15.3 p.ct. furfural;
oxidised with nitric acid it yielded 10.4 p.ct. mucic acid. Specimens from
the two first-named raw materials gave almost identical numbers.
Hydrolysis.—On boiling with dilute acids these products are gradually
broken down, dissolving without residue. In this respect they are
differentiated from the mucilages, which give a residue of cellulose
(insoluble). From the solution the author isolated crystalline galactose, but
failed to isolate a pentose. Dextrose was also not identified directly.
The tissue residues left after extracting the amyloid constituent, as above
described, were subjected to acid hydrolysis. A complex of products was
obtained, from which galactose was isolated. A furfural-yielding
carbohydrate was also present in some quantity, but could not be isolated.
The original seed tissues, therefore, contain an amyloid and a
hemicellulose, the latter differentiated in its resistance to water. Both yield,
however, to acid hydrolysis a complex of products of similar composition
and constitution.

UEBER DEN GEHALT DES TORFES AN PENTOSANEN
ODER FURFUROLGEBENDEN STOFFEN UND AN
ANDEREN KOHLENHYDRATEN.

H. v. Feilitzen and B. Tollens (Berl. Ber., 1897, 2,571).

CARBOHYDRATE CONSTITUENTS OF PEAT.

(p. 240) An investigation of typical peats taken at successive depths showed
increasing percentage of carbon, and inversely a decreasing yield of
furfural. The numbers may be compared with those for Sphagnum
cuspidatum—with C = 49.80 p.ct., and furfural 7.99 p.ct., calculated to dry,
ash-free substance:

Depth at which taken C p.ct. Furfural p.ct.
20-100 cm. 51.08 6.93
I. 100-200 " 53.52 5.30
200-300 " 58.66 3.19

Surface-20 " 55.47 3.40
20-60 " 55.06 3.48
II. 60-100 " 58.25 1.45
100-120 " 58.23 1.19
180-200 " 57.57 1.80

Cellulose was estimated by the Lange method. The yield from Sphagnum
was 21.1 p.ct.

From specimen I. at { 20-100 cm. 15.20
{100-200 " 6.87

From the peat of lower depths no cellulose could be obtained.
Hydrolysis (acid).—On heating with 1 p.ct. H2SO4 at 130-135°, soluble
carbohydrates were obtained, amongst which mannose was identified, and
galactose shown to be present in some quantity. After fermenting away the
hexoses, the residue was treated with phenylhydrazine and an osazone
separated. It contained 17.3 p.ct. N, but melted at 130°. The substance could
not be identified as an osazone of any of the yet known pentoses.

SECTION VIII. INDUSTRIAL AND
TECHNICAL. GENERAL REVIEW
The Industrial Uses of Cellulose.

C. F. Cross (Cantor Lectures, Soc. of Arts, 1897).

(p. 273) A series of three lectures, in which the more important industries in
cellulose and its derivatives are dealt with on their scientific foundations,
and by means of a selection of typical problems. In reference to textiles, the
small number of vegetable fibres actually available, out of the endless
variety afforded by the plant world, is referred to the number of conditions
required to be fulfilled by the individual fibre, thus: yield per cent. of
harvested weight or per unit of field area, ease of extraction, the absolute
dimensions of the spinning unit, and the proportion of variation from the
mean dimensions; the relative facility with which the unit fibre can be
isolated preparatory to the final twisting operation; the chemical constants
of the fibre substance, especially the percentage of cellulose and degree of
resistance to hydrolysis. It is suggested that any important addition to the
very limited number fulfilling the conditions, or any great improvement in
these, can only result from very elaborate artificial selection and cultural
developments on this basis.
The paper making fibres are shown to fall into a scheme of classification
based on chemical constitution, and consisting of the four groups: (a)
Cotton [flax, hemp, rhea], (b) wood celluloses, (c) esparto, straw, and (d)
lignocelluloses. Papers being exposed to the natural disintegrating agencies,
more especially oxygen, water (and hydrolysing agents generally), and
micro-organisms, the relative resistance of the above groups of raw
materials is discussed as an important condition of value. The indirect
influence of the ordinary sizing and 'filling' materials is discussed. The
paper-making quality of the fibrous raw materials is also discussed, not
merely from the point of view of the form and dimensions of the ultimate
fibres, but their capacity for 'colloidal hydration.' This is complementary to

the action of rosin, i.e. resin acids, in the engine-sizing of papers; and the
proof of the potency of this factor is seen in the superior effects obtained in
sizing jointly with solutions of cellulose and, more particularly, viscose and
rosin. Wurster's much-cited monograph of the subject of rosin-sizing ['Le
Collage des Papiers,' Bull. Mulhouse, 1878] neglects to take into
consideration the contribution of the cellulose hydrates to the total and
complex sizing effect, and hence gives a partial view only of the function of
the resin acids.
In further illustration of fundamental principles various developments in the
textile industries are discussed, e.g. the bleaching of jute, cotton, and flax,
and special developments in the spinning of rhea and flax.
The concluding lecture deals with later progress in the industrial
applications of cellulose derivatives, chiefly the sulphocarbonate (viscose);
the nitrates, in their applications to explosives, on the one hand, and the
spinning of artificial fibres (lustra-cellulose), on the other; and the cellulose
acetates.

La Viscose et le Viscoide.

C. H. Bardy (Bull. Soc. d'Enc. Ind. Nationale, 1900, March).

This is a report presented to the Committee of Economic Arts of the above
Society, dealing with the industrial progress in products obtained by means
of the sulphocarbonate of cellulose (viscose).
The following developments are noted:
Engine-sized Papers.—The viscose, by coating the fibres with regenerated
cellulose hydrate, adds very much to the tensile strength of papers. Increase
of 40-60 p.ct. is attainable by addition of cellulose in this form from 1-4
p.ct. on the weight of the paper.
Viscoid.—Solid aggregates are formed by incorporating viscose with
mineral matters, hydrocarbons, &c. Products are cast or moulded into
convenient forms, and, after purification and sufficient ageing, are available
for various structural uses.

Paint.—The viscose is used as a vehicle for pigments, the mixture being
used either as a paint or for coating papers with fine surfaces, such as
required in the reproduction of photo-blocks. In these applications the
extraordinary viscosity of the product conditions the economic use of the
cellulose in competition with oils, on the one hand, and organic colloids,
such as gelatine, casein, &c., on the other.
By suitable alteration of the formula for making the paint a product is
obtained which has an extraordinary power of removing paint from old
painted surfaces. The product has been officially adopted by the French
Admiralty, and receives extensive application in removing the paint from
ships.
Films.—Films are produced from the viscose itself in various ways. Plane
or flat by solidifying the viscose on glass surfaces, removing the by-
products and rolling the films. The film is also produced by applying the
viscose on textile fabrics, drying down, and fixing on a stenter machine,
then washing away the alkaline by-products from the fixed film. A large
number of industrial effects are obtained by suitably varying the mixtures
applied.
Cellulose-indiarubber.—The viscose, in its concentrated form, can be
incorporated with rubber-hydrocarbon mixtures, and these mixtures can be
used both as water-proofing films, as applied to textiles, or can be solidified
into the class of goods known as 'mechanicals.' The cellulose not only
cheapens the mixture, but produces new technical effects.
Spinning.—The viscose is spun by special methods, patented by C. H.
Stearn. As produced in thread form, the diameters are approximately those
of natural silk. In commercial form it is a multiple thread (of 15 or more
units) at from 50-200 deniers on the silk counts. It is a thread of high lustre,
and more nearly approaches the normal cellulose in chemical properties
than any of the other artificial silks. It can also be spun in threads of very
much larger diameter, which can be used as a substitute for horsehair, for
carbonising for incandescent electric lamps, &c.
Cellulose Esters.—These are conveniently made from cellulose,
regenerated from the solution as sulphocarbonate. The tetracetate is made
from this product on the industrial scale. Nitrates are conveniently made by

treatment with the ordinary mixed acids. For fuller details the original
report may be consulted.

VISKOS.

R. W. Strehlenert (Svensk Kemisk Tidskrift, Stockholm, 1900, p. 185).

A report on the industrial development of viscose, covering essentially the
same ground as the above.

Ueber die Viscose.

B. M. Margosches (Reprint from Zeitschrift für die gesammte Textil-
Industrie, 1900-01, Nos. 14-20).[11]

Report of Committee on the Deterioration of Paper.

(Soc. of Arts, 1898.)

(p. 304) The Report of a Representative Committee appointed by the
Society of Arts to inquire into the question of qualities of book papers in
relation to their several applications, and more especially for documents of
permanent value.
The report first discusses the two directions of depreciation of papers in
use: (1) Actual disintegration shown by loss of resistance to fracture by
simple strain, and by loss of elasticity—i.e. increase of brittleness; (2)
discolouration. These are independent effects, but often concurrent. They
are the result of chemical changes of the cellulose basis of the paper,
brought about by acids or oxidants used in the process of manufacture, and
not completely removed from the pulp, or by acid products of bleaching—
e.g. oxycelluloses or chlorinated derivatives; again, by the changes of starch
used as a 'sizing' agent, or by oxidations induced by rosin constituents when
the rosin is used in excess. Discolouration is an attendant phenomenon of
these changes, but is more frequently due to the presence of the lower-grade

celluloses (esparto and straw) and the lignocelluloses (mechanical wood-
pulp).
The physical and chemical qualities of papers depending primarily upon
their fibrous or pulp basis, and in a secondary degree upon the kind and
proportion of the constituents added for the purpose of filling and 'sizing,'
the report concludes with the following recommendations, positive and
negative, under these heads:
The Committee find that the practical evidence as to permanence fully
confirms the classification given in the Cantor Lectures on 'Cellulose,' 1897
[J. Soc. Arts, xlv. 690-696], and which ranges the paper-making fibres in
four classes:
(A) Cotton, flax, and hemp (rhea).
(B) Wood celluloses, (a) sulphite process and (b) soda and 'sulphate'
process.
(C) Esparto and straw celluloses.
(D) Mechanical wood-pulp.
In regard, therefore, to papers for books and documents of permanent value,
the selection must be taken in this order, and always with due regard to the
fulfilment of the conditions of normal treatment above dealt with as
common to all papers.
The Committee have been desirous of bringing their investigations to a
practical conclusion in specific terms—viz. by the suggestion of standards
of quality. It is evident that in the majority of cases there is little fault to
find with the practical adjustments which rule the trade. They are, therefore,
satisfied to limit their specific findings to the following—viz. (1) normal
standard of quality for book-papers required for publications of permanent
value. For such papers they specify as follows:
Fibres: Not less than 70 p.ct of fibres of class A; class D excluded.
Sizing: Not more than 2 p.ct. rosin, and finished with the normal acidity of
pure alum; starch excluded.

Loading: Not more than 10 p.ct. total mineral matter (ash).
(2) With regard to written documents, it must be evident that the proper
materials are those of class A, and that the paper should be pure and sized
with gelatin, and not with rosin. All imitations of high-class writing-papers
which are, in fact, merely disguised printing-papers, should be carefully
avoided.
Appendix.—To the Report is added 'Abstracts of Papers' in 'Mittheilungen
aus den Koniglichen Technischen Versuchsanstalten, Berlin,' for the years
1885-1896 inclusive—which is, in fact, a summary of the investigations of
the Institution in connection with paper and paper-standards.

(p. 273) Special Industrial Developments.—From the point of view of the
chemist there has been a very large development of the cellulose industries
during the last five years. This is not so much marked by the gradual and
progressive growth of the well-established industries, as by the success of
the newer ones, with the attendant forecast of enormous developments of
the industries in artificial products, the manufacture of which rests upon a
purely chemical basis. We can, of course, only treat them from this limited
standpoint, and so far as they involve and elucidate chemical principles.

I. Chemical Treatments of Raw Materials.

(a) Flax-spinning.—The treatment of the roving on the spinning-frame by
the addition of reagents to the macerating liquid—otherwise and usually hot
water—continues to be justified by results. The technical basis of the
process and the reactions determined in the spinning-trough by the alkaline
salts used—chiefly sulphite and phosphate of soda—is set forth in the
original work, p. 280. Since that time a sufficient period has elapsed to
judge the effects, both technical and industrial, by the results of a
commercial undertaking based on the exclusive use of the process. Such a
concern is the Irish Flax Spinning Company of Belfast. At this mill the
experience is uniform and fully established that by means of the process the
drawing, i.e. spinning, quality of inferior flaxes is very considerably

appreciated, enabling the spinner to use such flaxes for yarns of fineness
which are unattainable by the ordinary method of spinning through hot
water. Notwithstanding the success of this undertaking the development of
the method is still inconsiderable. It is none the less a further and forcible
demonstration of the existence of margins of increased technical effect
which it is the work of the scientific technologist to exploit.
(b) Wood-pulp and Methods of Manufacture.—There is a steady growth
in the consumption of wood-pulps (cellulose) relatively to other materials.
In regard to the paper-trade of the world, this continues to be one of the
most prominent characteristics of its evolution. In the United Kingdom the
conditions of its competition are of a more special kind by reason of the
firm foothold of esparto, which is a most important staple in the
manufacture of fine printings. Whereas the consumption of esparto remains
nearly stationary at about 200,000 tons per annum, the importation of
wood-pulps has shown the extraordinary rate of increase of doubling itself
every five years. But in the group 'wood-pulps' the trade returns have until
recently included the 'mechanical' or ground wood-pulps. From 1898 we
have separate returns for the chemical or cellulose pulps, and in 1899 the
tonnage reached nearly to that of esparto, with a total money value about 80
p.ct. greater. When it is remembered that this is one of the newer chemical
industries in cellulose products, and that these large commercial results
have been accomplished during a period of twenty years, we are impressed
with the scope of the industrial outlook to the chemist, afforded by the arts
of which cellulose is the foundation.
It may be noted that there have been no important developments in the
purely chemical processes involved in the several systems of preparing
cellulose from wood. The acid methods (bisulphite processes) have
developed much more extensively than the alkaline, the latter including the
caustic soda and the mixed sulphide ('Dahl') process. The bisulphite
processes depended in the earlier stages upon the efficiency of lead-lined
digesters. But the problem of acid-resisting linings has been much more
perfectly solved in later years in the various types of cement and other
silicate linings now in use. The relative permanency of these linings has had
an important effect on the costs of production. Further economies result
from the use of digesters of enormous capacity, dealing with as much as
100 tons of wood at one operation. As a combined result of economic

production and active competition, the selling prices of 'sulphite pulp' have
moved steadily downwards in relation to other half-stuffs and raw
materials. As a necessary consequence the prices of those which it has
gradually displaced have depreciated, and a study of the price and tonnage-
equilibrium as between rags, esparto, and wood-pulp over a series of years
forms an interesting object-lesson in the struggle for survival which is an
especial mark of modern industry. For these matters the reader is referred to
the special literature of the paper-making industry.[12]
It is not a little remarkable that the main by-product of these bisulphite
processes—the sulphonated derivatives of the lignone constituents of the
wood—is still for the most part an absolute waste, notwithstanding the
many investigations of technologists and attempts to convert it to industrial
use (see p. 149). Seeing that it represents a percentage on the wood pulped
equal to that of the cellulose obtained, it is a waste of potentially valuable
material which can only be termed colossal. Moreover, as a waste to be
discharged into water-courses, it becomes a source of burden and expense
to the manufacturer, and with the increasing restrictions on the pollution of
rivers it is in many localities a difficulty to be reckoned with only by the
cessation of the industry. The problem in such cases becomes that of
dealing with it destructively, i.e. by evaporation and burning. In this
treatment the obviously high calorific value of the dissolved organic matter
(lignone) appears on the 'credit' side. But where calcium and magnesium
bisulphites are used, the residue from calcination is practically without
value. It appears, however, that by substituting soda as the base the alkali is
recoverable in such a form as to be directly available for the alkaline-
sulphide or 'Dahl' process. As a more complicated alternative the soda
admits of being recovered on the lines of the old black-ash or Leblanc
process, and the sulphur by the now well-established 'Chance' process, for
which, of course, an addition of lime is necessary to the fully evaporated
liquors previously to calcining. The engineering features of the system, so
far as regards evaporating and calcining, are the same. For economic
working there is required (a) evaporation by multiple effect and (b)
calcining on the continuous rotary principle. For the latter a special
modification has been devised so that the draught of air is concurrent with
the movement of the charge in the furnace, securing a progressively
increasing temperature within the furnace. This interesting development of

the chemical engineering of wood-pulp systems has been elaborated by two
well-known technologists, Drewson and Dorenfeldt, and readers who wish
to inform themselves in detail of these developments are referred to the
various publications of these inventors.
Assuming the present necessity of a destructive treatment of the by-
products of the bisulphite processes, the scheme has many advantages. The
soda-bisulphite liquors are more economically prepared; the pulp obtained
is superior in paper-making quality to that resulting from the lime or
magnesia (bisulphite) processes: it is more economically bleached.
Then, as pointed out, the soda may on the one plan be obtained in a form in
which it is immediately available as a powerful hydrolysing alkali in the
manufacture of a 'soda' pulp. These two systems become, therefore, in a
new sense complementary to one another. Lastly, it is obvious that the
employment of soda as the base opens out a new vista for developing the
electrolytic processes of decomposing common salt.
The authors have assisted in preparing plans for a comprehensive industrial
scheme combining all these more modern developments. In this scheme it is
only the combination which is novel, and as it involves no new principles in
the chemical treatments of the materials we are not further concerned with
it than to have briefly sketched its economic basis. This may be summed up
in result in the important question of cost and selling price, and the estimate
is well grounded that by means of this scheme bleached wood-pulp can be
sold on the English market at 10l. a ton. It is important to note this figure
and to compare it with the prices of twenty years ago. The fall has been
continuous, notwithstanding the influence of the opposing factors of
increasing consumption, exhaustion of accessible supply of timber, and
relative appreciation of the essential costs of steam, chemicals, and labour.
It is important in forecasting the future, since the youngest and apparently
most promising of the 'artificial' cellulose industries employs wood-
cellulose by preference as its raw material (see p. 173).
As a last point it must be considered that as chemists we are bound to
anticipate the realisation of value in the soluble by-products of the
bisulphite processes. Outside the intrinsic interest attaching to the solution

of this problem, it carries with it the promise of a further economy in the
production of wood-cellulose.
Bleaching of Vegetable Textiles.—By far the largest of these industries are
those which are engaged in producing the 'pure white' on cotton and flax
goods. The process, considered chemically, is simply that of isolating a pure
cellulose, and we endeavoured to give due prominence to this view in the
original work. It is important to insist upon it for the reason that this view
gives the due proportion of chemical value to the several contributory
treatments—alkaline hydrolyses (caustic lime and soda boils), hypochlorite
oxidations, and incidental acid treatments (souring). The first of these is by
far the largest contributor of 'chemical work,' though the second, by being
the agent for the actual whitening effect or bleaching action proper,
occupies a position of often exaggerated importance.
In bleaching processes there has been no radical change of system on the
large scale since the introduction of the 'Mather' kier in 1885, and the
associated change from lime and ash boiling to the caustic soda circulating
boil with reduced volume of lye, which this mechanical device rendered
practicable. It is outside the scope of this work to follow up this branch of
technology in any detail, and we cannot discuss the evolution of systems on
variations of detail where no essential principle is involved. But we have to
notice a very recent development which has only just begun its industrial
career, and which does give effect to a principle of treatment not previously
applied. This is tersely stated by its originator, William Mather,[13] in the
expression, 'it is more economical to make liquids pass through cloth than
to make cloth pass through liquids.' The starting point of this development
is the invention of a complete self-contained machine in which a rolled
batch of cloth can receive a succession of chemical treatments, with
accessory washings—the solutions, or wash waters, being circulated
through the cloth. The essential fact on which this system is based is that a
perfect liquid circulation can be maintained from selvedge to selvedge
through the folds of a tightly rolled batch of cloth. Such circulation is
therefore quite independent of the diameter of the batch. If we consider a
cloth under chemical treatment with solutions, it is clear that the reactions
and interchanges of soluble matters within the cloth, within the twisted
elements of the yarn, and in the last grade of distribution within the actual
ultimate fibres, are subject to capillary transmission, and osmotic exchange.

There is a mixture of these molecular effects, with the circulation in mass,
sweeping both faces of the cloth. It is obvious that for the mass effect a
relatively very small volume of circulating liquid is necessary to maintain
uniform conditions of action. In the actual disposition of the machine the
rolled batch of cloth nearly fills the cylindrical space of what we may call
the reaction chamber, and the circulation of the liquid is maintained by a
circulating pump and a differential pressure in the horizontal plane across
and through the folds of the batch. This is in the meantime kept in slow
revolution. For a full description of these mechanical details the reader is
referred to the original patent specifications [Engl. Pat. 23,400, 23,401;
1900, W. Mather]. If we again consider the principles involved, they are
very much as set forth in our original work (pp. 288-291). Boiling processes
in which a relatively large volume of liquid is used are wasteful of steam,
the active agent is unnecessarily diluted or used in superfluous quantity, and
the soluble by-products, being continually removed as formed, cannot so
effectively contribute by secondary actions to the chemical work. The new
mechanical appliance enables us to further reduce the volume of liquid
required in the alkaline-hydrolytic treatment of vegetable textiles, and
where advantageous to bring the treatment down (or up) to a process of
steaming with the active agent dissolved in a minimum proportion of water
relative to the cloth. This concentration of effect is of importance in flax
cloth, and especially linen treatment, where the peculiarly resistant
cutocelluloses have to be attacked and a considerable proportion of waxy
by-products to be removed. These points are the basis of the special process
of Cross and Parkes [Engl. Pat. 25,076/ 99] for steaming flax (and cotton)
goods with an emulsion containing, in addition to the special hydrolysing
agent—caustic soda—mixtures of soap with 'mineral' or other oils, the
presence of which effectually aids the removal of the by-products in
question.
A complete system on these lines is now working on the industrial scale in
the Belfast district. The results are not merely economical in largely
reducing the number of alkaline boiling treatments required on the old plan
of pan or 'pot' boiling, but are visible in the strength and finish of the linens
so treated.
For cotton bleaching the costs may be put down at a fraction of those of the
Irish linen bleach. The economical advantages of the new system are

obviously less in relation to the lesser total costs. But there are other points
which have come into more prominent influence. The mechanical wear and
tear on the cloth is considerable in the ordinary process, more especially in
the mangle-washes. As a result the adjustment of warp and weft is more or
less disturbed. These defects are absent from a system which operates on
the cloth in a fixed position.
But as we are mainly concerned with the purely chemical factors we cannot
pretend to deal with textile questions. We have to notice the remaining
element of chemical economy as it involves a fundamental principle. The
practice of washing residues or products of reaction free from reagents and
soluble by-products involves a well-known mathematical law, under which
the rate of purification is a function rather of the number of successive
changes of washing liquid than of the volume of the latter. The ordinary
practice of textile washings entirely ignores this principle, and the
consumption of water in consequence may reach many thousand times the
economic minimum. With supplies of water often in indefinite excess of
requirements, even in this most wasteful method, bleachers are in no need
to consider the question of consumption. But leaving aside particular and
local considerations of advantage the fact is that the new system gives
control of the practice of washing, enabling the operator to adapt an
important element of the daily routine to a fundamental principle which has
been almost universally ignored.
In the oxidising processes which follow the alkaline treatments, the
hypochlorites are still the staple agents. Owing to the steady relative fall in
the selling prices of the permanganates these are coming into more
extensive use, but the consumption is still small, and they are mainly used
for certain special effects, chiefly in linen or more generally flax cloth
bleaching.
Paper-pulp Spinning.—Paper is a continuous web or fabric produced by
the interlocking of the structural fibrous units of the well-known short
length. In Japan and other countries paper is made to serve for all or some
of the purposes for which we employ string or twine, and to give the
necessary tensile strength the paper is twisted or rolled on itself. Such
twisting, however, adds nothing to the intrinsic tensile qualities of the
original paper.

A new technical effect is realised in this direction by the treatment of paper-
pulp in the process of its conversion into a continuous web: The pulp is
formed into continuous strips of convenient breadth (usually from 2 to 8
mm.), these receive a 'rolling-up' treatment immediately following the
squeeze of the press rolls by which the superfluous water is removed: they
are then further but incompletely dried, and in this condition are subjected
to a final spinning or twisting treatment on ring-spinning machinery of
special construction.
Such a process was originally patented by C. Kellner in this country (E.P.
No. 20,225/1891), and is fully described in his specification. Later
improvements in detail were patented by G. Türk (E.P. 4621/1892).
A joint system is now being industrially developed in Germany by the
Altdamm-Stahlhammer Pulp and Paper Company under the technical
direction of Dr. Max Müller, and there appears to be every prospect of the
product taking a position as a staple textile.
The process has only the incidental interest in connection with our main
subject, that it employs chiefly the 'chemical' pulps or celluloses as raw
materials. The industrial future of the application must, of course, be largely
determined by costs of production, as the directions of application in the
weaving industries will be limited by the necessarily inferior grade of
tensile strength belonging to these products and the degree by which this is
lowered on complete wetting. All these questions have been duly weighed
by those engaged in this interesting development, and the conclusion of
those qualified to judge is that the new industry has vindicated for itself a
permanent position.
II. The Chemical Derivatives of Cellulose, in their industrial aspects, have
come to occupy a profoundly important position in the world's affairs. In
the way of any essential alteration of the perspective from that obtaining in
1895 we have nothing to chronicle. No new derivatives of industrial
importance have been added in that period; but certain new methods
incidental to the preparation of well-known compounds or for converting
them into more generally available forms have been introduced, and these
are contributing to the rapid expansion of the 'artificial' cellulose industries.

Of the cellulose esters the nitrates are still the only group in industrial use.
There uses for explosives have attained immense proportions, and their
applications for structural purposes are continually on the increase. The
manufacture of smokeless powders on the one hand, and of celluloid and
xylonite (both in the form of films and solid aggregates) on the other, has
taken no new departure. The industry in 'artificial silks' or 'lustra-celluloses,'
by the collodion processes also, whilst presenting features of unusual
interest attaching to rapid expansion, has been barren of contribution of
fundamental scientific or technical importance. The tetracetate is now
manufactured on the large scale, but the product has yet to make its market.
The process of mercerising cotton yarns and cloth has been developed to an
industry of colossal dimensions, and the growth has been especially rapid
during the last five years. Significant of the technical progress in these two
industries, with their common aim of appreciating cellulose in the scale of
textiles by approximating its external properties in those of silk, is the
appearance of a monograph of the technology of each, notices of which
have been previously given (pp. 22-26).
There is little doubt, however, that the question of the future industry in the
various forms of cellulose, thread, film, structureless powder or solid
aggregate, obtainable by artificial means, mainly turns upon cost of
production. Irrespective of cost, there would, no doubt, be a market for all
these products, based upon such of their properties or effects as are
indispensable and not otherwise obtainable. As an illustration, we may cite
the extraordinary selling prices of 40-50 fr. per kilo, for the 'artificial silks'
(collodion process) which ruled some three years ago; and we may note that
for a special application of viscose the dissolved cellulose is paid for at the
rate of 10s. per lb. These facts are certainly worthy of mention, and should
be borne in mind as an index of some special features of modern
manufacturing industry. But with a material like cellulose rendered
available in a new shape the question which always arises more
prominently than that of limited uses at high prices is that of consumption
on the extensive scale which marks the older and well-known products.
That question is rapidly solving itself in this country as regards the 'artificial
silks.' There is at present a limited market at 9s.-10s. per lb., a price which
on the one side excludes extensive consumption, and on the other
practically bars manufacture in this country by any of the collodion

systems. It will appear from a very elementary calculation of what we may
call the theoretical costs that the above selling price would not have a
remunerative margin. The theoretical costs are made up of

Raw Cotton. Nitrating acid. Ether-alcohol (solvent).
materials[14] Denitrating chemicals.
(a) Nitrating and preparing collodion. Denitrating and
bleaching.
Labour
(b) Textile operations. Spinning. Winding and twisting.
Rewinding.
Making, filtering, and distributing collodion. Driving
Power
textile machinery.

Added to which are the costs of expert management and supervision and
general establishment expenses. It is evident that raw materials make up a
large fraction of the total cost; also that a very large item is the waste work
of converting the cellulose into nitrate, only to remove the nitric groups so
soon as the cellulose is obtained as thread.
It is clear that the aqueous solutions of cellulose have a double advantage in
this respect—not only do they readily yield an approximately pure cellulose
as a direct product of regeneration or decomposition, but the first cost of the
solution is very much less. With these newer products, therefore, the
spinning problem enters on a new phase of struggle. It is certain that at
selling prices at or about 5s. to 7s., very large markets will be open to the
product or products. The two processes which are or may be able to fulfil
this demand are those based (1) on cuprammonium solutions of cellulose,
(2) on the sulphocarbonate or viscose. As regards first cost of the solution
the latter has a large advantage. One ton of wood pulp (at 12l.) can certainly
be obtained in solution in a condition ready for spinning at a total cost
(materials) of less than 30l. The cuprammonium process, so far as 'outside'
information goes, requires for production of the solution (1) cotton as raw
material, (2) ammonia (calc. as concentrated aqueous) equal to 1-1/2 times
its weight, and (3) metallic copper 25 p.ct. of its weight; and the costs are
approximately 100l. per ton. It is obvious that the materials are recoverable
from the precipitating-bath, but at a certain added cost. We have no

statements as to the proportion recoverable nor the costs incurred, and we
are therefore unable to measure the total net cost of the regenerated
cellulose by this process. It is certainly much less than by the collodion
processes. As to the textile quality of the thread, the product has not yet
been on a sufficiently wide selling basis for that to have been determined.
There are a great many factors which enter here. Not merely the external
characters of lustre, softness, and translucency, but the all-important quality
of uniformity of thread. The collodion-spinning is a process still very
defective in this respect, and the defect is no doubt referable to the difficulty
of securing absolute physical invariability of the collodion. It is to be
regretted, in the interests of scientific development, that none of the
technologists who have published investigations of these processes have
entered into the discussion of the fundamental factors of the spinning
processes; we are, therefore, unable at this stage to discuss these elements
of a full comparison in greater detail. We cannot, for this reason, say how
far the cuprammonium process diverges in point of control from the
standard of the collodion processes. Of the 'viscose' product we have a more
intimate knowledge, and it certainly reaches a higher general standard than
the older and now well-known artificial silks. The process is also
sufficiently developed to enable the total costs of production to be estimated
at a figure less than one-half that of the 'collodion' processes. This would
assure to this system an entrée in this country, and a basis of expansion
limited only by the ordinary laws of supply and demand.
This prospect is opened up precisely at the moment when, for various
reasons connected both with the difficulties of manufacture and the
narrowing of the margin of profit, the proprietors of the two systems of
collodion-spinning have decided to abandon all idea of manufacturing by
these systems in this country.[15] We leave the discussion of the industrial
problem at this point.
In regard to other developments based upon the exceptional character and
properties of the sulphocarbonate, their further discussion will exemplify no
general principles; and as regards technical detail they have been dealt with
in the papers previously noticed.
As a purely general question, if there is to be any industry in these 'artificial'
forms of cellulose, commensurate with the magnitude that usually belongs

to the cellulose industries, it must come by way of a plastic or soluble form
prepared at low cost, and conserving the essential molecular properties of
the cellulose aggregate. These are the particular features of the
sulphocarbonate. The obvious difficulties in the way of its industrial
applications are those caused by the presence of alkali and sulphur
compounds. These are dealt with by appropriate chemical means; but the
fact that there is a special chemistry of the product has rendered its
industrial progress slow. The work of the last five years in this, as in other
applications of cellulose in its many derived forms, has resulted in a
considerable addition to the domain of practical chemistry.
Further developments will make an increasing demand upon our grasp of
the fundamental constitutional problems, to which it is the main purpose of
the present volume to contribute.

FOOTNOTES:
[11] This is the most complete notice that has appeared and the bibliography is
exhaustive. The publication comes into our hands too late to be noticed in detail.
[12] Text-book on Paper-making, Cross and Bevan (Spon, London: second
edition, 1900). Chemistry of Paper-making, Griffin and Little (New York, 1894:
Howard Lockwood & Co.). Handbuch d. Papierfabrikation, C. Hofmann
(Berlin). Paper Trade Review, London (weekly). Papier-Zeitung, Berlin.
[13] William Mather, M.P., of the firm of Mather & Platt, Limited, Manchester.
[14] The actual costs varying considerably in the various countries, we cannot
make any specific statement. But from estimates we have made, the costs of
obtaining cotton in filtered solution as collodion multiply its value by 12-14, the
denitrations adding further costs and raising this multiple to 18-20. In the same
estimates we arrived at the conclusion that the item for raw materials made up
60 p.ct. of the total cost of the yarn.
[15] The recent failure of a French company founded for the exploitation of the
cuprammonium process may be taken as showing that it presents very
considerable technical difficulties. It is a matter of common knowledge that this
company estimated the costs of production to be such as to enable the product to
be sold at 12 fr. per kilo., whereas the costs actually obtaining were a large
multiple of this figure.

INDEX OF AUTHORS
Bardy, C. H., 157

Bokorny, T., 43

Bronnert, E., 54

Bumcke, G., and Wolffenstein, R., 67

Buntrock, 25

Cross, C. F., 139, 152, 155

Cross, C. F., and Bevan, E. J., 92

Cross, C. F., Bevan, E. J., and Briggs, J. F., 118

Cross, C. F., Bevan, E. J., and Heiberg, T., 114

Cross, C. F., Bevan, E. J., and Smith, C., 101, 103, 105, 114, 145

De Haas, R. W. T., and Tollens, B., 151

Faber, O. v., and Tollens, B., 71

Feilitzen, H. v., and Tollens, B., 154

Fenton, H. J. H., 8

Fenton, H. J. H., and Gostling, M., 86

Fraenkel, A., and Friedlaender, P., 26

Gardner, P., 22

Gilson, E., 112

Hancock, W. C., and Dahl, O. W., 135

Hoffmeister, W., 96, 100

Kleiber, A., 97

Kröber, E., 121

Krüger, M., 119

Lange, H., 25

Lewes, V. H., 15

Luck, A., and Cross, C. F., 45

Margosches, B. M., 159

Morrell, R. S., and Crofts, J. M., 114

Mylius, F., 21

Nastukoff, H., 74

Omelianski, V., 76

Ruff, O., 117

Salkowski, E., 113

Schöne, A., and Tollens, B., 124

Seidel, H., 149

Sherman, H. C., 137

Simonsen, E., 146

Storer, F. H., 142

Strehlenert, R. W., 158

Suringar, H., and Tollens, B., 16, 124

Süvern, C., 63

Tollens, B., 148, 151

Tollens, B., and Glaubitz, H., 122

Vignon, L., 43, 70, 72, 94

Will, W., and Lenze, P., 41

Winterstein, E., 109, 144, 153

INDEX OF SUBJECTS
Acetone, action on cellulose nitrates of diluted, 46

Acid-cellulose, 68

Acids, volatile, from cellulose, 145

Æschynomene aspera, 135

Alcohol from cellulose and wood, 146

Alcoholic soda, mercerisation results with, 26

Alkali-cellulose, effects of long storage on, 31

Amyloid, vegetable, 153

Arabinose from gluconic acid, 117

'Ash' of plants, 13

Bacterium xylinum, 85

Barley plant, chemical processes in the, 103

---- straw, carbohydrates of, 105

Bleaching, 166

Bran, digestion of, 139

Brommethylfurfural, 8, 84, 86

Carbohydrates, action of hydrogen bromide on, 86;
action of hydrogen peroxide on, 114;
nitrated, as food for mould fungi, 43;
nitrates of, 41;
quantitative separation of, 96

Carbohydrates of barley straw, 105;
of wheat, 137;
of yeast, 113

'Caro's reagent,' 118

'Celloxin,' 71

Cellulose, alcohol from, 146;
constitution of, 77, 92;
fermentation of, 76;
industrial uses of, 155;
iodine reaction of, 21;
methods for the estimation of, 3, 4, 16, 19, 97;
nitration of, 43;
saccharification of, 73;
ultimate hydrolysis of, 11;
volatile acids from, 145

---- acetates, monoacetate, formation of, 40;
tetracetate, constitution of, 80

---- benzoates, 34;
from structureless cellulose, 36;
from three varieties of cotton, 35;
monobenzoate, properties of, 36;
dibenzoate, properties of, 37;
acetylation of, 130;
nitration of, 38

---- derivatives, commercial aspects of, 171;
saccharification of, 73

---- nitrates, 44, 45, 83;
structureless, 45, 51;
cupric reducing power of, 73;
instability of, 50, 53

---- sulphocarbonate, 27;
effects of the nature of the cellulose, 28;

---- —— solutions, analysis of, 32;
iodine reaction of, 33;
loss of carbon bisulphide, 33;
viscosity of, 30

Cell-wall constituents, 97

Cereal celluloses, 101, 105

Chitin, 112

Chlorination, Cross and Bevan's method, 19;
statistics of, 134

Chloro-lignone, 126

Collodion. See Silk, artificial

Cotton, lustreing effect of mercerisation, 23;
mercerised, structural properties of, 25;
pentosane content of, 148

'Crude fibre,' 17

Cuprammonium solvent, 21, 58, 173

Currants, pectin of, 152

Denitration of collodion silk, 56;
of jute nitrate, 133;
products of, 74

Dioxybutyric acid, 71

Elder pith, 137

Eriodendron, seed hair of, 92

Explosives, 44;
sporting powders, 52

Fermentation of cellulose, 76;
of furfuroids, 108;
of sugar from wood, 148

Fibres, report on miscellaneous, 139

Flax boiling, 168;
spinning, 161

Fodder plants, pentosanes of, 122

Fungi, tissue constituents of, 109

Furfural from cellulose, oxycellulose, and hydrocellulose, 70;
derivative from lævulose, 8;
estimation as hydrazone and phloroglucide, 119, 121;
oxidation of, 114, 118 (refer also 'Pentosanes')

Furfuroids, 8, 10, 102, 105;
assimilation of, 108

Gabriel's method of cellulose estimation, 18

Gluconic acid, action of hydrogen peroxide on, 117

Glucosamin, 112

Hemicellulose, 96, 97;
determination and separation of, 100

Hönig's method of cellulose estimation, 18

'Hydralcellulose,' 68

Hydrocellulose, 73;
nitration of, 43

Hydrogen peroxide, oxidations with, 114

Hydroxyfurfural in lignocellulose, 9, 116, 118

Incandescent mantles of artificial silk, 14, 15

Industrial appliances of cellulose, 155

Iodine reaction of cellulose, 21

Isosaccharinic acid, 71

Jute, composition of, 141;
quality of, 140;

treatment of, 142 (refer also Lignocellulose)

---- acetate, 129

---- benzoate, 127;
acetylation of, 130;
nitration of, 132

---- nitrate, 131

Ketoses, physiological importance of, 9

Lange method of cellulose estimation, 18, 98

Lead compounds of nitrated carbohydrates, 49

Lignin, 100

Lignocellulose, constitution of, 133;
esters of, 125;
hydroxyfurfural in, 9;
new type of, 135

Lignone complex, properties of, 126

'Lignorosin,' 151

'Lustra-cellulose.' See Silk, artificial

Malt, pentosanes of, 122

Mather system of boiling textiles, 167

Mercerization, 22; shrinkage during, 24

Mercerised yarn, strength and elasticity of, 25, 26

Methylhydroxyfurfural, 84

Mould fungi, nitrated carbohydrates as food for, 43

Mycosin, 113

Nitrated carbohydrates, lead compounds of, 49

Nitrates of carbohydrates, 41

Nitrocellulose (see Cellulose nitrates);
silk, 55

'Normal' cellulose, definition of, 27

Normal paper, 160

Oxycellulose esters, 72;
nitration of, 43;
researches on, 71, 72, 74;
résumé of properties, 94

Oxygluconic acid, 117

Paper, deterioration of, 155;
normal standard, 160;
pulp, spinning of, 169

Peat, constituents of, 154

Pectins, 151, 152

Pentosanes, 100, 109, 144;
constituents of cotton, 124;
constituents of fodder, 122;
estimation of, 121;
of seeds during germination, 124

'Permanent tissue,' 103

Phloroglucinol, 119, 121

Plant tissues, carbohydrates of, 96, 97, 99

Plants, source of unsaturated compounds in, 145

Powders, manufacture of sporting, 52

Saccharification of cellulose and derivatives, 73

Schulze method of cellulose estimation, 18, 98

Schweizer solution, 101

Seeds, pentosanes in germinating, 124

Silica in plant tissues, 13

Silk, artificial, 54, 62, 63, 172;
bibliography of, 60;
from cuprammonium, 58, 64, 173;
from nitrocellulose (collodion), 55, 63, 172;
from viscose, 59;
from zinc chloride, 59;
reactions of, 64

---- natural, reactions of, 64

Straws, 101, 105

Succinic acid from furfural, 118

Sulphite waste liquors, 149, 164

'Swedish' filter paper, 14

Tissue constituents, 99, 109

Trees, composition of trunk woods, 142

Viscose and viscoid, 157, 158, 159

---- silk, 59, 175

---- —— specific gravity of, 34 (refer also Cellulose
sulphocarbonate)

'Vulcanised fibre,' 20

Weende, method of cellulose estimation (crude fibre), 17, 98

Welsbach mantles, 14;
Clamond type, 15

Wheat grain, insoluble carbohydrates of, 137

Wood, alcohol from, 146, 148

Wood-cellulose, waste liquors, 149

Wood-gum, 144

Wood-pulp, processes, 162

Wood, trunks of trees, 142

Yeast, carbohydrates of, 113

Zinc chloride, artificial silk, 59;
solvent action of, 20

*** END OF THE PROJECT GUTENBERG EBOOK RESEARCHES ON
CELLULOSE, 1895-1900 ***

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

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

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
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.

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.

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.

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
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
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,
how to help produce our new eBooks, and how to subscribe to our email
newsletter to hear about new eBooks.