38 ANALYSES OF THREE COMMON INSECTICIDES 



green, forty-three of which showed more than fifty per cent, of 

 the trioxide, and eleven less. 



The proportions found in the samples analyzed at this sta- 

 tionare given in the following table : 



ANALYSES OF PARIS GREEN 



Per cent. 

 Manufacturers. arsenic trioxide. 



C. T. Reynolds & Co., New York, . . . 56.36 



Boston Color Co., ...... 55-90 



Sondheim, Alsberg & Co., New York, . . . 55-68 



James A. Blanchard, New York, "Lion Brand," . 56.69 



Nash, Winslow & Co., Boston, .... 55-35 



These results show no adulteration, being nearly up to the 

 theoretical composition. 



ANALYSIS OF LONDON PURPLE 



• 



London purple is prepared frotn a waste product obtained in 

 making aniline dyes, and consists mainly of calcium arsenite 

 and a dye-stuff. The mixture cannot well be constant in its 

 composition ; but so far as learned, the proportion of arsenic 

 trioxide varies no more widely than in Paris green. 



Four analyses of the article have been reported from as many 

 different agricultural experiment stations,* and the average 

 amount of the trioxide was forty-three per cent., or about three 

 fourths of the quantity contained in the more common insecti- 

 cide. 



The result of the examination of the single sample at this 



station is given below. 



Per cent. 

 Manufacturer. arsenic trioxide. 



Hemingway's London Purple Co., London, Eng- 

 land., Leggett & Brother, New York, li- 

 censed packers, ...... 37-56 



WHITE HELLEBORE 



White hellebore, the third insecticide examined, is a sub- 

 stance of a different nature from the others previously described. 

 It contains no arsenic, being a purely vegetable poison. It 

 may be prepared from two species of false hellebore ( Vera- 



•Cornell, Bull. i8 ; Florida, Bull. 14 ; South Carolina, Rep. iS?8 ; Vermont, Bull. 12. 



