Nov. 27,1916 Nicotine-Sulphate and Fish-Oil-Soap Sprays 
397 
another condition which must be considered before judgment is made 
concerning the importance of wetting power. In case the insects are 
thoroughly drenched with the solution, a much higher percentage of 
Fig. 2.—Efficiency and wetting-power gsaphs for group a, containing 5 pounds of soap, and group 3, con¬ 
taining 1 pound of soap plus varying amounts of nicotine sulphate. Wetting values are in the column 
on the right. 
mortality occurs than when the insects are struck by a few minute drops, 
as is usually the case in field spraying where the materials are applied 
at high pressure. Under the latter conditions wetting power is highly 
