CATECHU. 24J? 



Description — Cutch is imported in mats, ba.'^s, or boxes. It is a 

 dark broAYn, extractiform substance, hard and brittle on the surface of 

 the mass, but soft and tenacious "within, at least when newly imported. 

 Tlie large leaf of Dipterocarpus tuhercidatits Roxb., the Ein or E^\ghfii 

 of the Burmese, is often placed outside the blocks of extract. 



Cutch when dry breaks easily, showing a shining but bubbly and 

 slightly granular fracture. When it is soft and is pulled out into a thin 

 film, it is seen to be translucent, granular and of a brijjht oranjje-brown. 



When further moisten Pfl n.nd px; 



)SCone. it exhibits 



an abundance of minute acicular crystals, precisely as seen in gambier. 

 We have observed the same in numerous samples of the dry drug when 

 rendered pulpy by the addition of water, or moistened with glycerin 

 and viewed by polarized light. 



The pale cutch referred to as manufactured in the north of India, is 

 m the form of irregular fragments of a cake an inch or more thick, which 

 has a laminated structure and appears to have been deposited in a round- 

 bottomed vessel. It is a porous, opaque, earthly-looking substance of 

 a pale pinkish brown, light, and easily broken. Under the microscope 

 it is seen to be a mass of needle-shaped crystals exactly like gambier, 

 with which in all essential points it corresponds. We have received 

 from India the same kind of cutch made into little round cakes like 

 lozenges, with apparently no addition. The taste of cutch is astringent, 

 iollowed by a sensation of sweetness by no means disagreeable. 



Chemical Com 



Pegu 



which is the only sort common in Europe, when immersed in cold water 



sol\ 



disinte£?rates 



^ivmg and forming a deep brown solution. The insoluble part if 

 Catechin^ in minute acicular crystals. If a little of the thick chocolate- 

 hke liquid made by macerating cutch in water, is heated to the boiling 

 point, it is rendered quite transparent (mechanical impurities being 

 absent), but becomes turbid on cooling. Ferric chloride forms with this 

 solution a dark green precipitate, innnediately changing to purple if 

 common water or a trace of free alkali be used. 



Ether extracts from cutch, catechin. This substance has been in- 

 vestigated by many chemists, but as yet with discrepant results. It 

 apees, according to Etti (1877), w^ith the formula C^'ff '0^ when dried 

 at 80^ a By gently heating catechin, Catechutannic acid, C'R^O'', 

 ^produced: ^ ^ ^ 



Th 



2(a'ff'0') — OH^ = C''ll^O'\ 



and 



blackisl 



^^own almost insoluble substance is obtained by heating catechin with 

 concentrated hydrochloric acid at 180^': 



H^^O'^ — i OH^ = C^H=^0'\ 



Catech 



ffords Protocatechuic acid, 



^ H ^0H)2CO0H, and Phloroglucin, C^ff (OH) 



C"ff»0H2 OH-=r 4H • C'H''0' • 2C''H*'0'. 



h - 



