INSECTICIDES, PREVENTIVES, AND MACHINERY. 445 



with a blanket so as to retain all the heat. Stir h-om time to 

 time and add hot water until every particle of lime is reduced. 

 Then stir again and reduce with three gallons of water for every 

 pound of sulphur used. 



A Connecticut formula is ; 



Sulphide of potash 10 pounds 



Lime 10 pounds 



Water 20 gallons 



Dissolve the sulphide of potash in warm water, and with the 

 solution slake the lime. Mix thoroughly and add water to make 

 up the full amount. 



All these mixtures have their advocates, and all are useful to a 

 greater or less extent. A great deal depends upon the making, 

 and it becomes a matter of practice to recognize the completed 

 sulphide. Half an hour of boiling has been declared sufficient in 

 some cases, and two hours in others was not enough. 



As to the best time for making such applications, that is just 

 before the trees become dormant in fall or before they begin to 

 make a start in the very early spring. The mixtures may be 

 employed in place of whitewash in hen-houses and stables, and 

 will prove useful in destroying lice and mites. They are also 

 good disinfectants and germicides for such organisms as are 

 readily affected by sulphur. 



Sulphur alone is chiefly used against mites, in either green- 

 house or orchard. Red spider is sometimes controlled in houses 

 kept moist and warm by simply scattering flowers of sulphur on 

 the surface, the products of the slow decomposition being suf- 

 ficient to destroy the insects. In greenhouses, a barrel with 

 broken lump sulphur may be placed in a warm corner and filled 

 with water, stirring from time to time until the luke-warm liquid 

 becomes impregnated with decomposition products. This makes 

 an effective spray, and water may be added as fast as used so 

 long as any sulphur remains. In orange and other citrus groves 

 where mites are injurious, sulphur scattered over the soil is 

 useful, but more so in the moist climate of Florida than in Cali- 

 fornia. Sulphur dissolved with caustic potash, as described for 

 the Georgia wash on p. 444, may be directly diluted with water 

 so as to make one pound of sulphur for twenty-five gallons of 

 water, and this is useful as against mites and red spider of all kinds. 



