_ oil is not suitable for pharmaceutical purposes. — 
MALVACEAE. 227 
ing to a bright brownish-red. The same change takes place on 
keeping the bark for some time, when it yields a red tincture 
with alcohol. This substance was examined by Prof. Wayne 
(1872) and W. C. Staehle (1878), who regard it as of a resinous 
nature. The latter obtained about 8 per cent. of this sub- 
stance, which is soluble in 14 parts of alcohol, 15 of chloroform, 
23 of ether, and 122 of benzol; also in alkalies, from which 
solutions it is again precipitated by acid. The potassa solu- 
tion diluted with water is of a sage green tint. Glucose was 
likewise observed, and the aqueous solution of the alcoholic 
extract contained a principle which gave a purplish-black pre- 
cipitate with ferric chloride. ©, C. Drueding (1877) obtained 
also a yellow resin soluble’ in petroleum-benzine, a fixed oil, a 
little tannin and 6 per cent. of ash. (S#illé and Maisch.) Cot- 
ton seeds are small in size, and vary from ellipsoid to fusiform, 
and in colour from pale grey through yellow and brown to almost 
black. Of forty samples examined the amount of oil varied 
between 10 per cent. in an immature and badly dried Sea 
Island seed, to 29 per cent. in fully matured Egyptian seed. 
The albuminoids and other nitrogenous substances varied from — 
18 to 25 per cent., and the lignin from 15 to 25 per cent. One 
handred pounds of seed give on an average— 
Hills with lint , -49—A6 pounds, 
Cake 38—37 = 
Oil . ..16—14 ne 
The crude oil has 28 to 30 times the viscosity of water. Af 
20° ©. it has a specific gravity of -9283 and at 15° C. of -9306. — 
It congeals at —1°9C. to —2°-7 C. In taste and odour it | 
resembles linseed oil, and in other properties it is inter- — 
mediate between a drying and a non-drying oil. The refined 
oil has a specific gravity of *9264 at 15°C. and congeals at 
‘0°C. to —1:°1 CG. Chemically cotton seed oil consist of palmat 
and olein, and its ultimate percentage composition is ¢ 
76°40, Hydrogen 11°40, Oxygen 12:20. (Brannt.) Cotte 
