12 



Moisture at 100° C, 

 Arsenious oxide, 

 Copper oxide, 

 Calcium oxide, 

 Sulpliuric acid, 

 Magnesium oxide. 

 Potassium oxide, 

 Sodium oxide. 

 Insoluble matter, in diluted 



hydrochloric acid 1.40 .60 * * 



* Not (leterinined. 



An examination of the above stated analyses shows a material 

 difference in the composition of samples I., II., III., and IV. aa 

 compared with samples V., VI., VII., and VIII. The former, 

 samples I. to IV., represent evidently the standard variety of Paris 

 Green hitherto offered in our market ; see compilation of analyses of 

 Paris Green in my late annual report (1895). The samples V. to 

 VIll. consist of a different article. A pound box containing the 

 material was marked : '' The Lion Brand New Process Paris Green" 

 manufactured by James Blanchard, New York City, N. Y. ; samples 

 V. and VI. were bought last year and VII. and VIII. this year. 

 The difference does not consist so much in the average amount of 

 arsenious acid they contain, (from 54 to 55 per cent), as in the 

 diflerent percentage of copper oxide as well as the presence of a 

 ■comparatively large amount of other constituents, as lime, magnesia, 

 soda and sulphuric acid. 



As -the arsenious acid (white arsenic) is usually considered the 

 principal acting poison in the Paris Green, it seemed of interest to 

 make a few observations regarding the behavior of our different 

 samples towards cold and hot water. 



A. — One part of Paris green of samples I., II., III., IV., was 

 treated with 100 parts of cold water each for three days at ordinary 

 temperature. The resulting solution contained : 



Arsenious acid, 3.62 per cent. 



Arsenic acid. None. 



Copper oxide, None. 



