304 PROCEEDINGS OF THE AMERICAN ACADEMY. 



Passing excess of arsine through the solution in which the red body 

 is suspended, Partheil and Amort obtain a black precipitate to which 

 they give the formula AsoHga, and this derives support from the re- 

 actions with alkyl iodides described by these authors in a succeeding 

 paper. ^* The investigation is given somewhat more fully in a later 

 paper by Partheil. ^^ On partial precipitation of a mercuric chloride 

 solution by arsine, a yellow body was obtained, to which, from a single 

 analysis of an evidently impure substance, the formula AsHeHgCl was 

 assigned. From this experiment and from the results of Franceschi 

 and of Lohmann, Partheil considers that there should be added to the 

 two substances given above a third, with the structure 



-H 

 As-H 

 - HgCl 



"While the evidence appears to show that the hydrogen of arsine is 

 replaced by the mercurous chloride group to a greater or less extent, 

 the formula for the red substance does not seem to us to have been 

 conclusively proved, and the reactions of decomposition are decidedly 

 in doubt. Nothing has been brought forward to show definitely the 

 relation of the yellow compound or compounds, if such exist, to the red. 

 Lack of time prevents us at present from studying the reaction quanti- 

 tatively, but it is hoped that the investigation may be taken up later by 

 one of us. Nevertheless the following qualitative reactions have made 

 it possible to treat the bands of color so that they may be kept for a 

 considerable time, either in their original form or by means of a quasi 

 development and fixation. 



The removal of the relatively large excess of mercuric chloride from 

 the paper by treatment with absolute ether or alcohol did not offer a 

 solution of the difficulty, as the colors faded rapidly even when kept in 

 the dark and over sulphuric acid. The color is quickly bleached by 

 boiling with water, as is well known. Cold water acts more slowly, the 

 color not being completely changed until after a day or two, and then 

 not bleached, but converted to a dull gray. Bird,^^ and also Goode 

 and Perkin,^7 have observed the action of hydrochloric acid upon the 

 original color, which is thereby considerably changed. Goode and 

 Perkin also note the action of ammonia upon the original color, but do 

 not find the action of service in preparing standards. 



From the evident effect of even a slight amount of moisture we were 



" Ibid., 31, 596 (1898). " Archiv. d. Pharm., 237, 121 (1899). 



1* Loc. cit. " Loc. cit. 



