Ninth Report of the State Entomologist 415 



the same gentlemen, is repeated in still stronger terms — "he had utterly 

 ruined a valuable plum orchard by the use of London purple." The 

 statement was questioned at the time when made to this society, and 

 from what has subsequently been learned, we deem it proper to say that 

 there is hardly a remote prol)ability that the injury to the trees, caus- 

 ing the falling of the foliage, which followed the spraying, can be in 

 the least ascribable to the spraying, but was solely owing to a fungus 

 attack of the leaves. 



In recent experiments by Professor Bailey, of Cornell University, 

 conducted in the most careful manner, plum trees sprayed with one 

 pound of London purple to two hwidred gallons of water, were not 

 injured in the slightest degree. Although not so stated, it may be in- 

 ferred that the ordinary coarse spray was used — not the fine one, 

 which appears to be much more safe on delicate foliage. 



Experiments reported by Prof Gillette of the Iowa Agricultural 

 Experiment Station, show slightly differing results from the above, as 

 the same mixture gave a seven per cent injury to plum foliage. The 

 application, in this instance, was with the Woodason bellows-sprayer 

 or atomizer. {Bull. iVb. 10, loioa Agr. Exp. Station, August, 1890 , 



London purple on the peach. — The spraying experiments of Pro- 

 fessor Bailey have confirmed observations previously made by others, 

 that the foliage of the peach is more susceptible to injury from London 

 purple than other of the fruits. While it sustained no harm from one 

 pound of Paris green in two hundred and fifty-six gallons of water, 

 one of London purple four to hundred, caused slight injury. It is prob- 

 able that one to four hundred and fifty, applied in a fine mist-like spray, 

 could be used with entire safety; but as it is quite doubtful if this 

 degree of reduction would kill the curculio, it is advisable that Paris 

 green only, of the arsenites, t-hould be employed on the peach unless 

 other substances are combined with them. 



Solubility of London purple. — The greater liability to injury from 

 London purple is owing to its greater solubility in water. According 

 to Professor Bailey — " the arsenic in London purple is in the form of 

 a normal arsenite of calcium, which substance comprises about seventy- 

 two percent of the whole compound; and over fifty per cent (52.38) 

 of it, or nearly forty j)er cent of the London purple is quickly soluble 

 in water. (Bulletin ISFo. 18 of the Cornell University Agricultural 

 Experiment Stat io?i, July, 1890.) 



An efficient nozzle for low spraying. — Mention is made and illustra- 

 tion given, in the Bulletin from which we have quoted, of a bush nozzle 

 devised by Prof. Bailey, for use on low bushes, when the insects, like 

 the currant worm, feed largely on the underside of the leaves. The 



