EXUDATIONS, JUICES, ETC. 
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boxes or gourds, and occasionally it is found in com- 
merce inclosed in monkey skins. Socotrine aloes 
commands the highest price. 
Description. — Curacao Aloes. — In orange to blackish- 
brown opaque masses, translucent in thin pieces; frac- 
ture uneven, waxy, somewhat resinous, occasionally 
exhibiting microscopical crystals of aloin ; odor dis- 
tinct, unpleasant; taste nauseous, bitter. The powder 
is dark brown and gives an immediate deep reddish 
color with cold nitric acid or with solutions of the 
alkalies. 
Socotrine Aloes. — In yellowish-brown to dark-brown 
opaque masses, or smooth and glassy, fracture some- 
what conchoidal; odor saffron-like ; powder yellowish 
brown or brownish yellow, giving a yellowish or red- 
dish-brown color with nitric acid. 
Gape Aloes. — Of a reddish-brown or of an olive-black 
color, transparent in thin pieces; fracture smooth and 
glassy ; powder greenish yellow, becoming light brown 
and greenish with nitric acid. 
Constituents. — A crystalline, bitter principle aloin, 
the percentage (4‘5 to 25 per cent.) and composition 
of which vary in the different varieties, the Curasao 
aloin being distinguished from Socotrine and Cape 
aloin by giving a reddish color with cold nitric acid ; 
the drug also contains resin, emodin, volatile oil, and 
yields about 1 per cent, of ash. 
Adulterants. — Aloes is likely to contain various 
mechanical impurities, hence the necessity for a purified 
aloes. The aloin is sometimes removed, as in the 
Curacao aloes, which may then be sold for Cape aloes. 
CATECHU. 
An extract prepared from the heartwood of Acacia 
Catechu (Fam. Leguminosse), a tree indigenous to 
