EEPOET OF ANALYSES OF PAEIS GEEE^ 

 AND OTHEE IISTSEGTICIDES.* 



L, L. Van Slyke. 



SUMMAEY. 



In accordance with the provisions of a law designed to pro- 

 tect purchasers of Paris green, samples were secured during 1899 

 and the results are published in this bulletin. 



Paris green contains as its chief constituent a compound called 

 copper aceto-arsenite, which, when chemically pure, contains 



Arsenious oxide 58 . 64 per ct. 



Copper oxide 31 . 30 " 



Acetic acid 10.06 " 



In the 24 samples of Paris green examined, the arsenious 

 oxide varied from 55.34 to 60.16 per ct. and averaged 56.48 per 

 ct. The copper oxide varied from 2Y.70 to 30.90 per ct., and 

 averaged 29.97 per ct. The amount of arsenious oxide for each 

 pound of copper oxide varied from 1.82 to 2.17 and averaged 

 1.88 pounds. The onlj adulterant that could be. found was white 

 arsenic and this was excessive in only one sample. The general 

 result of the examination is to show a good quality of Paris green 

 in the market at the time the samples were taken. 



Partial analyses are given of the following materials: Para- 

 grene. Black Death, Slug Shot, London Purple, Laurel Green, 

 Smith's Electric Vermin Exterminator, Bug Death. 



INTRODUCTION 



During the past ten years the use of Paris green has very rap- 

 idly increased, owing to its efficiency as an insecticide. There 



• 



Reprint of Bulletin No. 165. 



