336 Simple method for the 



The only objections that can be urged against this process 

 are, that arsenic may exist as an impurity in the hydrochloric 

 acid employed ; and that other metals, under similar circum- 

 stances, may be deposited upon copper, as I shall presently 

 show is the case with mercury and antimony. In reply 

 to the first objection it may be stated, that it is an extremely 

 rare occurrence for hydrochloric acid to contain an arsenical 

 impurity ; and that, when it does, it may always be guarded 

 against by boiling the copper in a portion of the acid before 

 adding the suspected liquid. To the second objection it may 

 be answered, that from no other metallic deposit whatever 

 can a sublimate be obtained having properties which can 

 possibly be mistaken for those of arsenious acid. 



This simple method of Reinsclr's has been generally appli- 

 ed to the detection of arsenious acid, but I have used it with 

 equal facility and success in separating arsenic, existing as 

 orpiment, from the contents of the stomach of a native woman 

 who was found poisoned by orpiment administered to her by 

 a native doctor, with the supposed intention of producing 

 abortion. In this case, I separated the arsenic both in the 

 metallic state and as arsenious acid, and to the latter suc- 

 cessfully applied the three characteristic tests. This process 

 also will succeed equally well with powdered arsenic, and 

 with all oxydes and sulphurets of the metal. 



The Poisonous compounds of Mercury. 



Those causes which generally render the application of the 

 more usual methods for the detection of arsenic difficult 

 under the circumstances to which I have referred, equally 

 affect the ordinary processes for determining the presence of 

 the soluble poisonous compounds of mercury : but, for- 

 tunately, they may, with the same facility, be obviated by a 

 process as simple as that of Reinsch for the separation of 

 arsenic from its compounds. 



Where the requisite means are at hand, and sufficient con- 

 fidence can be placed in the experience of the operator, 



