314 REporT OF THE DEPARTMENT OF ENTOMOLOGY OF THE 
the spray, and the quick evaporation after its application, the 
results obtained would hardly form a good basis for determin- 
ing the probable length of time that soluble ingredients are 
present and act as efficient insecticides in a wash applied under 
ordinary orchard conditions. This would certainly vary with 
the amount of rain and sunshine following the application. 
EXPERIMENT II. 
The principal object of this experiment was to determine how 
long after its application the wash would retain its insecticidal 
properties when submitted to severe daily drenching with water. 
Incidentally the direct insecticidal properties of ‘the soluble 
compounds were brought out. The results obtained should in- 
dicate the conditions upon treated trees, especially during a 
wet season. 
For the experiment a glass plate, of the size previously stated 
under Experiment I, was flooded with 3 ounces of lime-sulphur- 
salt wash and allowed to dry thoroughly. The coating of the 
wash thus formed was thoroughly dry in 24 hours and was then 
sprayed with one ounce of water applied with an atomizer. 
The residue was caught as before and immediately sprayed 
upon infested apples. This was continued on each of six suc- 
cessive days, the same glass plate with the wash receiving the 
same treatment with water each time, but the residue was ap- 
plied to a different apple each day, so that the first apple (No. 
8 of Table III) received the residue obtained by spraying the 
plate the first time, the second apple (No. 9 of Table III) the 
residue obtained by spraying the plate the second time, and so 
on until all the apples were treated. A summary of the treat- 
ment is given in the following table: 
