SELECTING AND PREPARING MATERIALS 289 



Another method which may be used without a platform 

 is to fill the spray tank about three-fourths full with water. 

 Dilute the copper sulfate stock mixture with part of the re- 

 maining water, start the agitator, and pour the copper sulfate 

 into the tank ; dilute the stock solution of lime with the balance 

 of the water, and pour it into the tank. 



Bordeaux mixture will attack iron and steel. Use brass, 

 bronze, or porcelain-lined spraying equipment where possible, 

 and flush it out with clean water immediately after use. 



d : 3. Consider the preparation of tank-mixed lubricating- 

 oil emulsions. The Cornell Experiment Station at Ithaca, 

 New York, gives the following directions for tank mixed 

 emulsions. 



The tank-mixed emulsions are prepared by several formulas. Many 

 growers prefer to emulsify the oil in the tank, using Hgnin-pitch as the 

 emulsifier. With the agitator running, put about 10 gallons of water in 

 the tank or enough so that pump can work. Wash % pound of lignin- 

 pitch through the screen by means of the spray gun. When it is thor- 

 oughly^ dissolved in the water, add the proper quantity of oil slowly 

 with the agitator running and with the spray gun turned into the tank. 

 When it is emulsified, add the full amount of water and spray out at 

 once. The quantity of lignin-pitch required will depend on the water 

 used. If the mixture foams too much, reduce the quantity. 



Another method is as follows : Place sufficient water in the spray tank 

 so that the pump can work. Do not start the engine. For each 100 

 gallons of spray, add 1 pound of copper sulfate dissolved in water, then 

 add 2 pounds of hydrated lime also in water, stirring meanwhile with a 

 stick or paddle. Start the engine, and slowly pour in the proper num- 

 ber of gallons of oil to give the percentage desired in the completed 

 mixture. Direct the spray gun into the tank and continue the agitation 

 until the oil is properly emulsified. In a few minutes or as soon as the 

 oil is thoroughly emulsified, fill the tank with water, keeping the engine 

 running continuously until the tank has been sprayed out. If it is 

 necessary to stop the sprayer, and any considerable quantity of oil 

 separates out (streaks of free oil floating on the surface), the remainder 

 in the tank should be discarded unless it can be brought back into an 

 emulsion. If more copper is desired for fungicidal purposes, use 3 or 4 

 pounds of copper sulfate and twice as many pounds of hydrated lime. 



