95 ACACIA CATECHU 



ing cutch in cold water, when the catechu-tannic acid is dissolved, 

 forming a deep brown-coloured solution; and the catechin which 

 is nearly insoluble in cold water is left behind as a mass of minute 

 acicular colourless crystals. Catechin is, however, soluble in 

 boiling water, and also in alcohol, and ether. Catechu-tannic acid 

 is distinguished from gallo-tannic acid by its solution yielding a 

 greenish precipitate with the persalts of iron ; and by not causing 

 a precipitate in a solution of emetic tartar. A minute quantity 

 of quercetin, a yellow crystalline substance, may be extracted from 

 a cold aqueous solution of cutch by means of ether, as first ascer- 

 tained by Lowe. 



Medical Properties and Uses. The properties and uses of this 

 kind of catechu are the same as those of pale catechu; they are 

 described under Uncaria Gambler. 



Per. Mat. Med., vol. ii, pt. 2, p. 340; Pharmacograpliia, p, 213; 

 U. S. Disp., by W. & B., p. 240; Royle's Illustrations, p. 182; 

 WoodviUe's Med. Bot., vol. ii, pi. 66, p. 183; Steph. & Church., 

 Med. Bot., by Burnett, vol. ii, pi. 76; Madden, in Journ. Asiat. 

 Soc. of Bengal, vol. xvii, pt. 1 (1848), p. 565; Watts' Diet. 

 Chem., vol. i, p. 816 ; Gmelin's Chem., vol. xv (1862), p. 515 ; 

 Fresenius, Zeitschrift fur Anal. Chemie (1873), p. 127. 



DESCRIPTION OF PLATE. 



Drawn from a specimen in the British Museum, collected in India by 

 Dr. Roxburgh. 



1. A branch with flowers. 



2. A flower. 



3. Section of a flower. 



4. A pod. 



5. A seed, 



(2, 3 enlarged.) 



