242 THE APPLE 



EMULSIFIER 



Carbolic acid (crude liquid i oo per cent) .... 2 quarts 



Fish oil 2i quarts 



Caustic potash (granulated) 1 pound 



Heat to 300 degrees F., remove from the fire, and immediately add : 



Kerosene 3^ quarts 



Water 5$ quarts 



These quantities will make 13 gallons of the complete soluble 

 oil or 416 gallons of the spray mixture. It may be made up in 

 any quantity and kept indefinitely. The cooking is best done in 

 an iron kettle — the ordinary kettle or caldron such as is commonly 

 used on the farm for making soft soap will answer the purpose. 

 It should have a cover and be so arranged that it can be readily re- 

 moved from the fire. Since the mixture is inflammable when hot, 

 the kettle should not be more than half filled, to allow for foam- 

 ing, and the fire must be kept from blazing up around the top. 

 The cooking should not be done inside or near a building, unless 

 a steam-coil or jacketed kettle is used. A good thermometer 

 graduated to about 320 degrees F. will be necessary. 



The various materials should be added separately in the order 

 named and while the whole is being stirred. The resultant mix- 

 ture will thicken up and present, except for its darker color, the 

 appearance of soft soap. 



2. Although the soluble oil will remain in good condition for 

 a long time, the second part of the formula should be prepared 

 just before using. 



THE COMPLETE SOLUBLE OIL 



Emulsifier 8 parts 



Crude petroleum 18 parts 



Rosin oil 4 P arts 



Water 1 part 



By securing the materials in large quantities the soluble oil 

 may be made for 16 cents or 18 cents per gallon. If diluted 

 with 1 5 parts water, as recommended, the spray mixture costs 

 slightly over 1 cent per gallon. In view of the fact that its 

 tendency is to spread when applied to the tree, and that it can be 



