13 



One part of the same Paris green was treated with 100 partsof 

 water at SC C. for three hours and filtered while still hot. The 

 solution tested without delay contained : 



Arsenious oxide, 15.67 per cent. 



Copper oxide, None. 



The same solution contained, after standing thirty-six hours : 

 Arsenious acid, 3.39 per cent. 



Arsenic acid, None. 



Copper oxide. None. 



B. — Sample of " Lion Brand New Process Paris Green " : 

 One part of samples VII. and VIII. was treated with one hundred' 

 parts of cold water each for three days. The solution contained : 

 Arsenious acid, 3.38 per cent. 



Copper oxide, None. 



One part of samples VII. and VIII. was treated with one luindredi 

 parts of water each at 80° C. for three hours, filtered while still hot. 

 — The resulting solution tested at once contained : 



Arsenious acid. 



Arsenic acid. 



Copper oxide. 



From these observations it ^ill be noticed that the different 

 samples tested by us contained on the average similar amounts of 

 arsenious acid in their cold solutions. Observations concerning 

 the action of dry Bordeaux mixture when added to either kind 

 of our Paris greens for spraying purposes are under way and 

 the results will be reported in one of our next bulletins. 



An addition of one pound of common British gum (Dextrine) for 

 every pound of Paris green used, holds, after drying, the latter in< 

 place : — 



