ME. ABEL’S EESEAECHES ON GUN-COTTON. 
215 
Table VI. 
Description of 
Volume of gas evolved. 
Gas escaped 
from the 
tube on 
- Condition of the gun-cotton after 3 months’ 
exposure 7 hours daily to 65° C. 
gun-cotton. 
5 th day. 
12th day. 
28th day. 
No. 1. Fine yarn, 
Waltham. 
cub. centims. 
57-6 
cub. centims. 
213-3 
cub. centims. 
13th day 
Strong acid reaction ; strength of fibre and ex- 
plosiveness diminished. Aqueous extract 
contained nitric and oxalic acids, and reduced 
cupric salts readily. Proportion of matter 
soluble in ether and alcohols 15 per cent. 
No. 2. Coarse yarn, 
Waltham. 
9-6 
161 
47-3 
65th day 
Acid reaction ; strength of fibre and explosive- 
ness not appreciably diminished. Aqueous 
extract contained nitric acid and a trace of 
oxalic acid ; reduced cupric salts to a very 
slight extent. Matter soluble in ether and 
alcohol=49-l per cent. (2 per cent, in ori- 
ginal sample). 
No. 3. Fine yarn, 
Waltham, washed 
and impregnated 
with 0'4 per cent, 
of sodic carbonate. 
No. 4. Coarse yarn, 
Stowmarket. 
273 
192-2 
67-7 
221-7 
30th day 
6th day 
Strongly acid reaction ; strength of fibre and ex- 
plosiveness only slightly reduced. Aqueous 
. solution contained nitric acid and a small 
quantity of oxalic acid ; reduced cupric salts 
slightly. Soluble matter =10 per cent. 
Acid, friable ; explosiveness very much dimi- 
nished. Large proportion soluble in water. 
Solution contained a very small quantity of 
nitric acid, but a large proportion of oxalic 
acid ; reduced cupric salt very abundantly. 
Portion insoluble in water; dissolved inether 
and alcohol. 
The sample of Stowmarket gun-cotton which decomposed so readily at 65°, was an 
early specimen of manufacture from that establishment ; it had evidently been prepared 
from inferior or very imperfectly purified cotton, and contained a considerable proportion 
of foreign matter extractable by alcohol. The two specimens of fine yarn (Nos. 1 
and 3) were portions of the lowest class of products obtained at Waltham Abbey. 
Its impregnation with a small proportion of sodic carbonate imparted to it greater 
power of resisting the effects of heat ; this result was not demonstrated, however, to its 
full extent, because the sample of the gun-cotton (No. 1) in its original condition con- 
tained some earthy carbonates, which had been at any rate partially separated from the 
sample impregnated with sodic carbonate. 
The specimen of coarse yarn (No. 2), which was found to be but little changed by the 
three months’ exposure to 65°, was an average specimen of the products obtained at 
Waltham Abbey. 
Specimens 1, 2, and 3 have been preserved in stoppered bottles in the condition in 
which they were removed from the bulbs, and have been exposed to strong daylight for 
two years. They have not undergone further change. 
Experiment 109. — A sample (20 grms.) of perfectly dry Waltham Abbey gun-cotton, 
representing the ordinary product of manufacture, was exposed in a bulb-tube exhausted 
over mercury to 65° C., for seven hours daily. The mercury-column was very gradu- 
ally depressed, as in the preceding experiments with gun-cotton of this kind, and after 
the experiment had continued for ten weeks, the gas escaped from the opening of the 
tube. In about one week more, sufficient gas was collected for examination ; it was 
found to consist of — 
2 g 2 
