IV. EXrERIMENTS WITH GREEN ARSENITE.* 



During the latter part of May, 1896, the Adhn- Color and Chemi- 

 cal Works of New York sent to the Station one hundred pounds 

 each of three arsenicals manufactured by them, and which they 

 designated as follows: Green arsenite, compound arsenite, and 

 pink arsenite. The superiority of these arsenicals over Paris 

 green is supposed to lie in the fact that, instead of being chrys- 

 talline, they are very fine amorphous powders, also that 

 they can be manufactured at a less cost than Paris green. 

 The percentage of arsenic was not given, although they are sup- 

 posed to be e(j|ual to Paris green in poisonous qualities. Only one 

 of these poisons was used in these exi>€riments, namely, the 

 green arsenite. 



The Objects of the Exteiumeivts 



were as follows: First, to determine the length of time that the 

 green arsenite will remain suspended in water; second, to deter- 

 mine its poisonous qualities as an insecticide; and third, to de- 

 termine the relative danger of burning the foliage. It may be 

 added here that it was the original intention to have a chemical 

 analysis of the arsenical made before any of the experiments 

 were commenced, but unfortunately the analysis was not forth- 

 coming and is not yet completed. 



Experiment No. 1. 



To a two quart jar of water enough green arsenite was added 

 to make the poison and the water in the proportion of one pound 

 to 150 gallons. The mixture was then stirred so that the green 

 arsenite was w^ell disseminated in the jar. It was then allowed 

 to remain untouched, with the result that the green arsenite had 

 not entirely settled to the bottom of the can until three hours 

 after mixing. 



• Sheele's green. 



