488 Vegetable Fibres Available, &e. 
to oxidise the carbon present. Where the chlorine com- 
bines with the substance, its ultimate action is still to 
liberate oxygen, when oxidation takes place. Oxidation is 
combustion, which, in its exact degree, must alter the aggre- 
gation of the substance.. The chlorohydric acid generated 
by the union of the chlorine and the hydrogen within 
the pores of the substance will hydrate itself at the ex- 
pense of the elements of water in the substance, and will 
thus aid still further to alter its aggregation. Conse- 
quently, to say that bleaching can take place by the ac- 
tion of chlorine under proper management without causing 
loss of strength to the substance bleached is speaking com- 
paratively. Nothing is better known in every household 
than that loss of strength is always sustained by articles 
thus bleached ; and it cannot be that every instance arises 
from mismanagement. The lustrous coat of the cell of 
fibres is likewise considerably altered by chlorine. The 
operation of chlorine in every possible combination has not 
been examined so minutely as that of other agents; yet 
there seems to be little probability that by any modifica- 
tion in its use, if employed more largely than is usually re- 
quired for careful bleaching, a satisfactory process will ever 
be perfected. All samples yet produced by its use show a 
diminution of from 40 to 80 per cent. of the native strength 
of the cell. It will beseen that the use of chlorine, even as 
a bleaching agent for these fibres, is attended with many 
disadvantages: some improved mode of bleaching is de- 
sirable which would be unaccompanied with the loss of 
strength inevitably resulting from the existing methods of 
chlorine bleaching. 
Having considered briefly the action of alkalis, of acids, 
and of chlorine in the operation, we have nearly exhausted 
the routine of treatment. There are, however, some means 
which have been recommended and which merit investiga- 
tion. Amongst these are putrefactive fermentation, and 
superheated steam. We propose next month to conclude 
this inquiry by an examination of the action of these agents. 
Foots Cray Mills, S.E., April 22, 1867. 
