230 
ME. ABEL’S EESEAECHES ON GUN-COTTON. 
cipated, to have sustained a greater loss than would have been caused by the extraction 
of the alkaline base entirely in the form of nitrate. The gun-cotton soluble in ether and 
alcohol now contained in the specimen amounted to 6 - 98 per cent.; the material ori- 
ginally contained 2'3 per cent., the increase amounted therefore only to 4' 6 8 per cent. 
The proportion of nitrogen-oxides which would have been liberated by the reduction to 
that extent of trinitrocellulose even to the lowest of the substitution-products would 
not have sufficed to decompose the sodic carbonate present. It would appear from 
these results that the principal effect of the very long-continued exposure of this 
“ alkalized” gun-cotton was to establish' a very gradual action of the alkaline carbonate 
upon the gun-cotton (resulting in the production of glucic acid, &c.), and that even the 
first stage of decomposition (consisting in the reduction to soluble gun-cotton) caused 
simply by the action of heat upon the ordinary material, only proceeded to a very slight 
extent during the sixteen days’ treatment. 
Experiment 147. — 6’5 grms. of gun-cotton were impregnated with 0‘38 grm. of sodic 
carbonate. The sample was thoroughly dried and exposed to 100°, as in the preceding 
experiment. After the lapse of three days a weighed sample of the gun-cotton was 
examined. It had darkened somewhat, was alkaline, and exhibited no change of pro- 
perties. After six days’ exposure it was still alkaline, and its solubility in ether and 
alcohol had not increased appreciably ; upon the ninth day the sample was found to be 
neutral. The experiment was then stopped, the gun-cotton was extracted with water, 
and the proportion of nitrogen-acids existing in it as sodium-salts was determined by 
means of nascent hydrogen. The result showed that less than four-tenths of the sodic 
carbonate employed had been neutralized by those acids, the remainder existing in com- 
bination with organic acids. Traces of ammonia were evolved during the treatment of 
the gun-cotton in this and the preceding experiment, and the loss in weight sustained 
by the material was greater than would have been occasioned by the simple expulsion of 
carbonic acid from the carbonate. The solubility in ether and alcohol of the sample 
had only increased to about double the original proportion. 
It was of course impossible actually to demonstrate by experiment whether the small 
proportion of organic acid produced in these experiments, which exhibited the proper- 
ties of reducing cupric oxide in an alkaline solution, was glucic acid, resulting from the 
action of the alkali upon the gun-cotton, or whether it consisted of the pectic acids found 
in the products of spontaneous decomposition ; but as abundant proof exists that the 
latter are only the products of a secondary change resulting from the action upon gun- 
cotton of liberated nitrogen acids (see especially experiments 155 and 156), there appear 
to be very good grounds for the conclusion that the results observed in these experiments 
were mainly ascribable to the action of the alkaline carbonate upon the gun-cotton and 
the organic impurities present, and that the effects exclusively due to the protracted 
exposure of the substance to 100° were limited to the liberation of a very small propor- 
tion of nitrogen-acid, which was at once neutralized, the only change produced in the 
gun-cotton consisting therefore in the decomposition of the small quantities of compara- 
