330 PHARMACOPEIAL DRUGS 



thin. The ouabaio poison, liberally referred to by Bur- 

 ton, according to our present state of knowledge is de- 

 rived from a species of Apocynacece. The making of 

 this poison among the Somali is attended with the same 

 mystery thrown about the strophanthus arrow poison. 

 The wood is chipped and then boiled with water in an 

 earthenware pot for hours or even days, until a pitch- 

 like extract is obtained, which is smeared upon the iron 

 arrow point. To prevent the poison from rubbing off, 

 the barb is surrounded with parchment-like prepared 

 goat skins or plant fibers, which are removed imme- 

 diately before use. To test this poison, the Somali 

 scratches his arm until the blood flows; he then applies 

 the poison to the lower end of the bloody pool, and 

 watches the blood coagulating from below upward, 

 estimating thereby its virulence. This appears to 

 anticipate some phases of scientific thought such as 

 the blood test for the cobra virus. 



In 1882, some roots, stems and leaves of the plant 

 yielding the Somali poison were sent to France by 

 Revoil and investigated by Arnaud. In 1888 Arnaud 

 obtained from similar specimens an active principle, an 

 amorphous glucosid that he called ouabain. For this 

 substance he arrived at the formula CHO,j. This 

 differs by the group CH, from the formula for strophan- 

 thin, Ci.HO,i, which he obtained from S. hispidus, 

 D. C. He therefore concluded that strophanthin 

 represents the higher homologue of ouabain. Besides, 

 both substances have identical physiological action, 

 which differs in degree only. 



PHARMACOPEIAL RECORD OF STROPHANTHUS. Be- 

 cause of its recent introduction into medicine, only late 

 editions of the different Pharmacopeias carry strophan- 



