486 Vegetable Fibres Available for 
number of the organic acids present in fibres possess a 
much slighter affinity for bases generally than do the in- 
organic acids. The combinations are, therefore, easily dis- 
turbed by the latter, and made to form new arrangements 
of a character, at least, more soluble, through their fresh 
formation. And so general is the power exercised by them 
of solving the substances deposited on ligneous fibres, that 
the whole extraneous matter, aided by the detergency of 
soap, becomes tolerably soluble; whilst the lustrous coat of 
the cell, not being much affected by them, retains its bril- 
liance. Their action is well exemplified in the preparation 
of paper pulp from wood, which is thus now effected with 
a considerable degree of success in Switzerland, France, and 
Belgium. But a satisfactory degree of success in producing 
paper pulp may be attained by a method producing results 
far from satisfactory in fibres for textile purposes. The 
papers for which wood pulp has hitherto been employed, are 
of a class in which strength is less important than fair ap- 
pearance with lowness of price. When sufficient attention 
has been awakened on the subject, it will be found that even 
for pulps it is desirable to retain all the native excellencies 
of the fibres. Let us look at the effect produced on cel- 
lulin by these agents. This substance contains the elements 
of water in exact proportions to form water; consequently, 
as it also contains no nitrogen, it is exceedingly liable to 
change, and the action of these acids is inevitably to cause 
it in a greater or less degree (varying with time of exposure, 
heat, and strength of acid solution) to approximate towards 
glucose. We find the strength of the cells, whilst their ap- 
pearance is retained, to be affected even by an hour’s ex- 
posure to water at boiling heat, only perceptibly acidulated. 
If containing two percent. of acid, by longer exposure, 
the strength will be diminished fifty per cent. Further, 
the experience of past years is fully against the possibility 
of this mode of treatment proving satisfactory. These 
acids have been extensively employed to destroy the cotton 
and linen in rags of mixed animal and vegetable fibres, by 
converting the latter into an imperfect dextrin, and re- 
taining the nitrogenous animal matter in a_ state less af- 
fected by them. From-this it may be logically reasoned 
that, in preparing fibres, the use of a less powerful acid 
solution only induces a less complete conversion of the 
cellulin; and that if the matter we wish to remove, 
which contains more or less of nitrogenous substances, be 
altered so considerably as to become soluble, the cellulin 
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