INSECTICIDES, PREVENTIVES, AND MACHINERY. 443 



salt in water enough to do it quickly, and add slowly to the 

 hoilin;^ mass. When all is thoroughly mixed together, and has 

 boiled at least one hour, add water enough to make uj) the one 

 hundred and fifty gallons and apply as soon as possible thereafter. 

 The mixture spreads better and works easier while warm ; if 

 allowed to settle, so that crystals begin to form, the wash is use- 

 less. The salt adds nothing to the effectiveness of the combina- 

 tion, but docs add to its adhesiveness and to llu* mechanical 

 condition which favors easy spraying. It may be materially 

 reduced or omitted altogether ; but I favor its retention. If 

 ground sulphur is used, the boiling should Ik; continued a little 

 longer to make sure of a perfect solution. Many formulas de- 

 mand a greater proportion of lime, but I consider that a dis- 

 advantage, because it thickens the wash, makes it take more to 

 cover, prevents it from getting into crevices so well, and favors 

 early scaling off. The boiling may be done in o})en kettles, or 

 in barrels by steam, which may b(.' furnished by any tyi)e of 

 boiler. 



Instead (;f salt, blue vitriol is favored in Oregon and some 

 other localities as adding to the fungicidal (jualities of th(; wash, 

 and f(jur and one-half pounds of crystals may be used instead of 

 the fifty pounds of salt. The crystals are dissolved in hot water, 

 and the solution is added gradually to the boiling lime and 

 sulphur. 



Next to the boiled wash in effectiveness are the combinations 

 in which caustic soda is used to help the unicjn of lime and 

 sulphur. The formula that has succeeded well in my hands 

 originated in New York State, and is as follows : 



Lime, — stone or shell, — ^ood (luality 33 pounds 



Sulpliur flowers 17 pounds 



Caustic soda, 75 per cent, or over 5 pounds 



Water 50 gallons 



Slake two-thirds of the lime with hot water enough to prevent 

 burning or drowning, and during the process sift over and stir in 

 half of the sulphur. Then add the remainder of the lime with 

 mcjre hot water, and, as the boiling continues, stir in the balance 

 of the sulphur ; add water as needed, stirring to help the combi- 

 nation. While the mixture is yet steaming add two [)ounds of 

 caustic soda, which will cause a violent boiling, and before that is 



