1820.] Scicutific Intelligence 389 



This approaches very nearly to six atoms carbon and one 

 atom azote ; for 



6 atoms carbon = 4-50 



1 atom azote = 1 "75 



Now 4-5 : 1-75 :: 34-2 : 13*3. If we suppose this analysis 

 correct, the equivalent number for animal charcoal will be 6*25, 

 or some multiple of it. 



We are already acquainted with two other compounds of 

 carbon and azote, pointed out and analyzed by Gay-Lussac. 



1. Azoturet of carbon composed of three atoms carbon and 

 one atom azote. 



2. Cyanogen composed of two atoms carbon and one atom 

 azote. 



III. Antidote for Vegetable Poisons. 



M. Drapiez has ascertained by numerous experiments that the 

 fruit of the Fewillea cordifo'.ia is a powerful antidote against 

 vegetable poisons. This opinion has been long maintained by 

 naturalists, but I am not aware that it was ever before verified 

 by experiments made on purpose in any part of Europe. M, 

 Drapiez poisoned dogs with the rhus toxicodendron, hemlock, 

 and nux vomica. All those that were left to the effects of the 

 poison, died ; but those to whom the fruit of the fewillea cordi- 

 folia was administered, recovered completely after a short illness. 

 To see whether this antidote would act in tlie same way, when 

 applied externally to wounds into which vegetable poisons had 

 been introduced, he took two arrows which had been dipped in 

 the juice of manchenille, and slightly wounded with them two 

 young cats. To the one of these, he applied a poultice, com- 

 posed of the fruit of the fewillea cordifoha, while the other was 

 left without any application. The former suffered no other 

 inconvenience, except from the wound^ which speedily healed ; 

 while the other, in a short time, fell into convulsions and died. 



It would appear from these experiments^ that the opinion 

 entertained of the virtues of this fruit in the countries where it is 

 produced is well founded. It would deserve in consequence to 

 be introduced into our pharmacopoeias as an important medicine ; 

 but it is necessary to know that it loses its virtues, if kept longer 

 than two years after it has been gathered. 



IV, titrate of Silver. 



M. Brandenbourg has pointed out an economical method of 

 separating silver from copper, or of making pure nitrate of silver, 

 from an alloy of silver and copper, which is an object of some 

 importance to practical chemists. His method is as follows : 



He dissolves the alloy of silver and copper in nitric acid, and 

 evaporates the liquid to dryness in a glass vessel. The salt is 

 then put into an iron spoon, and exposed to a moderate heat, 

 keeping the salt in a state of fusion till all ebullition is at an end. 



