CRUDE DRUGS. 673 



Constituents of Sumatra Benzoin. — About 75 per cent, 

 of a resinous substance, benzoresin, which consists of two esters : 

 (a) an ester of cinnamic acid and resinotannol (92.6 per cent), 

 and (b) an ester of cinnamic acid and benzoresinol. Benzoresin 

 on decomposition yields 30.3 per cent, of cinnamic acid, 64.5 per 

 cent, of RESINOTANNOL, which is soluble in a concentrated sodium 

 salicylate solution, and 5.2 per cent, of benzoresinol. 



Sumatra benzoin also contains traces of eenzaldehyde and 

 benzol; 0.1 to I per cent, of vanillin; i per cent, of the phenyl- 

 propyl ester of cinnamic acid; 2 to 3 per cent, of styracin (cin- 

 namic cinnamate) ; and 14 to 17 per cent, of insoluble matter 

 consisting chiefly of woody tissues. 



Constituents of Siam Benzoin. — It consists largely of a 

 resinous substance, siabenzoresin, which is composed of about 

 90 per cent, of an ester of benzoic acid and siaresinotannol, and 

 about ID per cent, of an ester of benzoic acid and benzoresinol. 

 Siabenzoresin on saponification yields 38.2 per cent, of benzoic 

 acid, 56.7 per cent, of siaresinotannol, and 5.1 per cent, of 



BENZORESINOL. 



Siam benzoin also contains 0.3 per cent, of a neutral aromatic 

 LIQUID, which is probably an ester of benzoic acid, the nature of 

 the alcohol not having been determined as yet; 0.15 to 1.5 per 

 cent, of vanillin; a small quantity of free benzoic acid, and 1.3 

 "•^o 3-3 pc cent, of impurities in the form of woody tissues. 

 Penang Benzoin has an odor of styrax, but resembles in its 

 composition Siam benzoin. It sometimes, however, contains but 

 little cinnamic acid and considerable benzoic acid, thus resembling 

 the Sumatra variet)^ 



MYRRHA.— MYRRH.— The dried gum-resin from the stem 

 of Commiphora abyssinica and C. Schimperi (Fam. Burseracese), 

 large shrubs (Fig. 160) indigenous to Northeastern Africa 

 (chiefly Somali Land) and Southern Arabia (p. 310). The gum- 

 resin exudes spontaneously or from incisions made in the bark; 

 it is first of a yellowish color but soon hardens, becoming darker, 

 and is then collected. There are two principal commercial varie- 

 ties of Myrrh, the one known as African or Somali Myrrh, and 

 the other as Arabian or Yemen Myrrh, the former being consid- 

 ered the better. 



43 



