REVIEWS — Taylor's treatise on poisons. 289 



in Grermany the same position that Dr. Taylor does in England, it is 

 not worthy of even a brief description in our standard work on 

 Toxicology. 



In endeavouring to prove that our author is incorrect in all these 

 assumptions, and has been far too hasty in forming a decision without 

 the test of experiment, it appears to be desirable to compare each 

 step of the two processes, the chemicals employed, and the results 

 obtained ; but it may be remarked that the objection with regard to 

 the number of chemicals used is of very little value to any one much 

 engaged in these investigations, because he would naturally provide 

 himself with a large stock of materials proved by himself to be pure, 

 and would keep them for such purposes solely. 



The process recommended by Dr. Taylor may be designated as I., 

 that to which he objects so strongly as II., and each operation will 

 be placed side by side, so that an idea may be obtained of the compar- 

 tive complexity of the two processes, together with observations on 

 each ; it may be remarked also that the process II. is not exactly that 

 recommended by Eresenius and Babo, but is the improved plan de- 

 scribed by Otto, but which is by no means simpler than the original 

 one : — 



A I. The mass is heated with sulphuric acid. Very offensive odours 

 are given off, and the operation is a lengthy one. The organic 

 matter is not entirely removed even by long digestion, and there is 

 great danger of a loss of arsenic. If chlorides be present, and 

 they almost always are, the action of sulphuric acid will be to form 

 volatile chloride of arsenic. It must be remembered that the 

 quantity of poison present in the solid tissues is usually very 

 SDiall. 



II. The mass is gently heated in a water bath with hydro-chloric 

 acid and chlorate of potassa added. Chlorine is evolved and the 

 operation can be finished in half an hour, or with the liver and 

 kidneys in one hour at most. The organic matter is not entirely 

 destroyed, but no arsenic can be volatilized. 

 The sulphuric acid used in No. I. must be pure, and the hydro- 

 chloric acid in No. II. must be the same. Here we have, however, 

 an extra chemical, chlorate of potassa, the purity of which has to be 

 ascertained, but as this salt never does contain arsenic, and is one of 

 the purest salts in general use, the objection is not of much value. 



