24 



Scientific Proceedings (94). 



Toxicological tests of the arsphenamine made by this method 

 have been favorable but this study is not yet complete. 

 While the physical properties are somewhat different than the 

 usual arsphenamine, which has one molecule of methyl alcohol 

 in its solid or crystal form according to Ehrlich and Bertheim, the 

 chemical tests, analyses and toxicological reactions of the new 

 substance are in harmony with pure dihydrochloride of diamin- 

 odioxyarsenobenzene with one or two molecules of water of crys- 

 tallization. 



Our experience with the methyl alcohol method has brought 

 to our attention three possible objections against using this 

 method : 



(a) Our main objection to the methyl alcohol or any other 

 similar solvent is based on the idea that it is easily oxidized or 

 reduced, and as a concomitant with arsphenamine, a substance 

 easily oxidized to very toxic and dangerous products, is apriori 

 not a safe thing to have. In a subsequent paper we expect to 

 prove these and other points. 



(b) Our second objection to this method is expense. Even in 

 peace times this method would be expensive. 



(c) Our third objection is that these solvents are highly in- 

 flammable. 



The advantages of the hydrochloric acid method are : 



(a) The medium of precipitation, both the water and the hydro- 

 chloric acid can be absorbed by common and inexpensive absorb- 

 ents and they are not easily oxidized or reduced. 



(b) It is an inexpensive method, as the excess hydrochloric acid 

 can be recovered ready for use by simple distillation. 



(c) It is a non-inflammable method. 



(d) It is pharmacologically more suitable and less open to 

 question. 



(e) The product seems more stable and less liable to oxida- 

 tion, when exposed to the air. 



(/) The method can be used for reprecipitation and is chem- 

 ically better calculated to eliminate impurities as it is the same 

 method used to obtain chemically pure sodium chloride. 



