180 On the Classification of Poisons, [Sept. 



The platina wire being considerably thicker than the silver, 

 the part A B will balance the projecting part of the silver wire 

 d e f C, A wire is attached to «? e at right angles with a small 

 weight to counterbalance B D C. 



P. S. The electromagnetic multiplier mentioned in your num- 

 ber for June, is, I perceive, a similar instrument to that which I 

 used and described as a Galvanoscope two years and a half since, 

 in a paper published in our Cambridge Transactions, and with 

 which all my present experiments were made. 



Very sincerely yours, 



J. CUMMING. 



Article III. 

 On the Classification of Poisons. 



[This article is taken from a work lately published on Medical 

 Jurisprudence, by J. A. Paris, MD. FRS. &c. and J. S. M. Fon- 

 blanque, Esq. Barrister at Law. It would not be consistent 

 with our plan to enter minutely into an account of a work of this 

 nature. It contains, however, so much curious matter con- 

 nected with chemical science, on the subject of nuisances and 

 poisons, that we intend, in a future number, to give from it, and 

 other sources, a general and comprehensive view of the methods 

 of examining substances suspected to contain poison, with 

 observations and additional experiments on the subject. In the 

 mean time, we present the reader with the classification of 

 poisons adopted by the above-mentioned authors. — Edit.'] 



Poisonous substances have been very differently arranged by 

 different authors, each appearing to have adopted a classification 

 best suited to promote the particular views and objects of his 

 own pursuit ; tnus, the botanist and chemist, engaged in the 

 examination of the physical characters by which poisons may 

 be individually distinguished and identified, have very judiciously 

 erected their system upon the basis of natural history. The 

 pathologist, whose leading object is the investigation of the 

 morbid effects which follow the administration of these agents, 

 with equal propriety and justice, prefers a classification deduced 

 from a generalization of the symptoms they are found to occa- 

 sion; while the physiologist, who seeks to ascertain through 

 what organs, and by what mechanism, they destroy hfe, may be 

 reasonably expected to arrange the different poisons under divi- 

 sions corresponding with the results of so interesting an inquiry. 



To meet the comprehensive views of the forensic toxicologist, 

 an arrangement would seem to be required, that should at once 

 embrace the several objects which we have just enumerated ; 



