80 Remarks upon Arsenic. 



follows, (which I have convinced myself is correct.) "That the 

 taches obtained from phosphite and sulphite of ammonia and tur- 

 pentine, differ from those of arsenic — 1st, By being but partially 

 soluble in cold nitric acid, and 2d. By the nitric acid solution 

 when evaporated to dryness, giving with nitrate of silver, a yel- 

 low and not a red precipitate." 



MM. Danger and Flandin, and still later the committee so 

 often referred to, have examined also the bones, but were no 

 more successful in tracing the presence of arsenic in them than 

 they were in the case of the muscles. M. Orfila, one of the first 

 who stated that they did contain arsenic, is no longer of his origi- 

 nal opinion; so that at present the question of the existence of 

 normal arsenic in the animal economy, is resolved in the nega- 

 tive ; and happy it is for the medico-legalist that he is not embar- 

 rassed on that point. I may also add that humanity should re- 

 joice at it, for did arsenic exist in the body normally, and was it 

 generally known, its use as a destructive agent would be consid- 

 erably extended, and those using it in a criminal way, might very 

 justly suppose, that if they were suspected and tried, nothing 

 would be easier for an ingenious attorney, than to snatch him 

 from the hands of justice, by forcing certain doubts from the 

 most skillful medico-legalist ; but whereas, as the question now 

 stands, facts are too easily brought to light and too well substan- 

 tiated, that a doubt should be left upon the mind of any one. 



There have been many other taches mentioned, but as they all 

 except one, depend upon the liquid of the apparatus being thrown 

 out by the gas upon the cooling surface, where any metallic salt 

 that it may contain is subsequently decomposed by the hydrogen, 

 no notice shall be taken of them, as the tube D (in the apparatus 

 figured) prevents altogether, any thing of the kind happening. 

 The tache excepted is that produced, when we use a surface 

 whose glaze contains lead or tin in considerable quantity ; the 

 flame of the hydrogen reduces these metals at that point of the 

 surface upon which it is directed, and gives rise to a tache more 

 or less brilhant, although very easily distinguished from that of 

 arsenic by being non-volatile, and insoluble in nitric acid. 



As regards the tache produced by antimony, there is nothing to 

 be said ; for when we treat the matter for examination by sulphu- 

 ric and nitric acids, antimony, if it be present, is converted into 

 antimonious acid, which is insoluble in water ; so there is no dan* 



