INJURIOUS INSECTS OF 1903. 115 



this mixture. He obtained excellent results "in using a 

 lime-sulphur wash, consisting of 25 pounds of lime and 20 

 pounds of sulphur to 60 gallons of water. The lime 

 added, a sufficient quantity of water is brought nearly to a 

 boil in a kettle, and while the slaking is in operation the 

 sulphur is put in and the whole well stirred, in order to 

 take advantage of the heat generated by the slaking lime. 

 This assists materially in bringing the sulphur into solu- 

 tion, and we find it necessary to boil the combination but 

 30 minutes." — Country Gentlemen, Nov. 12, 1903. 



36. Liver of Sulphur — (See Potassium Sulfid.) 



37. London Purple — 



This is a common arsenical insecticide, although not 

 used as much as formerly. It is a waste product in aniline 

 dye manufacture. It is cheaper than Paris Green and ■ 

 is held in suspension in water longer, but the composition 

 is very variable and more of the arsenic is in a soluble 

 form than in Paris Green, therefore it is more dangerous 

 to foliage, and is not recommended. 



38. Lye, Washing Soda, Etc. — 



These are in popular favor, but. experiments show them 

 to be of not much use. When trees are dormant one 

 pound of lye to three gallons of water may be used on the 

 limbs of the trees. For trees in foliage i pound to 40 gal- 

 lons of water, but this will kill only the very tender in- 

 sects, and stronger than this will burn the foliage. 



39. Naphthaline, Gum Camphor, Moth Balls — 



All these are simply repellants ; that is, the odor from 

 these is disagreeable to the insects and they keep away. 

 Moth balls are a combination of the first two. They are 

 used against museum pests, clothes moths, etc. (See 

 Carbon Bisulphid.) 



40. Paragrene — 



This arsenical insecticide contains too much free ar- 

 senious acid to be good. It is sure to burn the foliage. 

 (Cal. Bui. 126, 1899.) 



