366 



Identification of the false Angustura. 



[April 



The first hint we meet of the true natureof this bark occurs in the 

 valuable Manual of Materia Medica, by Vavasseur and Edwards, in 

 which, p. 269, the authors observe, — " This substance, obtained from 

 South America, is probably yielded by a strychnos yet undescribed, and 

 not by the Brucea anti-dysenterica," &c. 



Lastly, in Dr. Christison's unrivalled work on poisons, last edition, 

 October 1835, p. 806, we find the author observing—" It was long sup- 

 posed to be the bark of the Brucea anti-dysenterica, but the latest 

 inquiries seem rather to point at its being the produce of a species of 

 strychnos, and perhaps of the familiar species, S. Nux Vomica. 



Such is a fair outline of the history of this bark up to the latest 

 period. Since the last meeting of the Society I have been enabled to 

 clear up all doubts on the subject, and to identify the false angustura 

 as the bark of the nux vomica tree. 



The subject was brought to my notice by my having been intrusted 

 with the analysis of a crystalline substance supposed to have been pre- 

 pared from the bark of the Rohun tree (Swietenia febrifuga). My 

 experiments shewing that the crystals were brucine with traces of 

 strychnine, the presumption immediately arose that the bark from 

 which the crystals were obtained was the bark of the strychnos nux 

 vomica, the only poisonous strychnos aoundant in the Bengal jungles 

 with which the natives are familiar. 



Specimens of the bark from which the crystals were prepared, of the 

 Icuchila (native name of nux vomica bark) from the bazars, and from a 

 strychnos nux vomica tree in the Botanical Garden, kindly supplied by 

 Dr. W allien, were readily procured and compared with each other — all 

 were found identical in their physical and chemical composition, all 

 yielded brucine and traces of strychnine, and all produced the same 

 toxicological effects. 



On a reference to the characters assigned by the authorities I have 

 quoted as distinctive of the false angustura, we find the following 

 chemical tests — 1st, nitric acid, which changes the interior of the bark 

 to a blood-red colour, and causes the red external exuberance to become 

 green ; 2dly, the prussiate of potash which causes in an infusion of the 

 bark a faint green colour; and 3dly, sulphate of iron, which changes the 

 infusion to a deep green. To all these re-agents the nux vomica bark 

 presents the described indications. 



The most remarkable and curious of the external characters of the 

 nux vomica bark, and one in itself an indisputable proof of its being the 

 false angustura, is the' singular red exuberance which occurs on the 

 outer surface of the specimens now presented to the Society. 



This red exuberance was the first property of the spurious angustura 

 bark which attracted attention in Europe. M. Fee states that it fre- 

 quently happens that " the false angustura has a spongy exuberance of 

 a very beautiful rust colour, and that M. Pelletier who had analysed it 

 had by mistake described it as a lichen of the genus Chiodecton. 



