detection of Poisonous Compounds. 343 



teristic sulphuret thrown down by sulphuretted hydrogen.* 

 If sulphuretted hydrogen be passed through the tube in which 

 the oxyde of antimony has been deposited, the sulphuret 

 will at once be formed and recognised by its orange-red 

 colour ; but however distinctive this may be, it will be found 

 much preferable to obtain a solution of the oxyde as above 

 recommended, from which the other characteristic reactions 

 of antimony may be obtained. 



By the above process, I have been able to procure a sub- 

 limate of the oxyde of antimony from ~th of a grain of tartar 

 emetic dissolved in one drachm of distilled water ; indicating 

 a degree of delicacy in the process much greater than could 

 be essentially requisite in any medico-legal case whatever. 



All methods for the detection of antimony, equally with 

 those for mercury, and the above process in common with 

 others, serve only to prove the existence of the metal in some 

 state of combination possessed of solubility, and do not point 

 out what the particular combination is. But in the case of 

 antimony, this circumstance is of still less importance than in 

 that of mercury ; as tartar emetic is the only salt of the oxyde 

 of antimony, in a soluble form, which is likely to become 

 the subject of inquiry. 



General Remarks on the foregoing Processes. 



It will be found on comparing the three foregoing processes, 

 that the principle on which they are founded is the same 

 in all of them. In each there is effected a metallic deposition 

 on copper ; but in the case of arsenic the metal is readily oxy- 

 dised at a moderately elevated temperature ; in that of mer- 

 cury, the pure metal is sublimed in the characteristic state of 

 liquid globules ; and in that of antimony the oxyde is formed 



* It is better, if possible, to make use of a tube of hard German glass, 

 both because it sustains the requisite degree of heat better, and is also free 

 from lead, which is apt to be separated from the common kinds of glass, 

 and thus to contaminate the oxyde of antimony ; and in this way interfere 

 with the appearances afforded by sulphuretted hydrogen. 



2 Y 



