Ny FARMERS’ BULLETIN 1723. 
First dissolve the soap in boiling water; then remove the vessel 
from the fire. Immediately add the kerosene, and thoroughly agitate 
the mixture until a creamy solution results. The stock emulsion 
may be more conveniently made by pouring the mixture into the 
tank of a spray pump, and pumping the hquid through the nozzle 
back into the tank for some minutes. The stock solution, if well 
made, will keep for some months, and is to be diluted before use. 
To make a 10 per cent spray (the strength for trees in foliage) add 
to each 1 gallon of the stock solution about 53 gallons of water. 
For 20 and 25 per cent emulsions (for use on dormant trees and plants) 
use respectively about 24 and 13 gallons of water for each 1 gallon of 
stock emulsion. Agitate the mixture in all cases, after adding the 
water. The preparation of the emulsion will be simplified by the use 
of a naphtha soap. No heat will be required, as the kerosene will 
combine readily with the naphtha soap, in water, when thoroughly 
agitated. Double the quantity of naphtha soap given in the above 
formula, however, will be required, and soft or rain water should be 
used in making the emulsion. In regions where the water is ‘“‘hard”’ 
this should first be broken with a little caustic potash or soda, as 
common lye, before use for dilution, to prevent the soap from com- 
bining with the lime or magnesia present, thus liberating some of the 
kerosene, or rain water may be employed. 
CRUDE PETROLEUM EMULSION. 
Crude petroleum emulsion may be prepared in identically the same 
way as has just been described for kerosene emulsion, crude petroleum 
being substituted for kerosene. The grade of crude petroleum 
employed in the East is that known as “‘insecticide oil,”’ having a spe- 
cific gravity of 43° to 45° Baumé. The same dilutions for winter and 
summer spraying should be observed as stated for kerosene emulsion, 
but it should be noted that for summer treatments of trees in foliage 
the kerosene emulsion is preferable, as it is less hkely to cause mjury. 
FISH-OIL SOAP WASH. 
There are several brands of fish-oil soap on the market. Potash 
soap is preferable, and it should not contain over 30 per cent of water. 
For spraying dormant trees the soap is dissolved in hot water at the 
rate of 2 pounds to each 1 gallon, and spraying should be done before 
the wash cools, otherwise it is forced through the nozzle with dif- 
ficulty. For spraying trees in foliage use the soap at the rate of 1 
pound to 3 or 4 gallons of water, or even weaker. 
