348 PLUM. 



Kerosene and Soap Mixture. — ** To make this I use one- 

 fourth of a pound of hard soap, preferably whale-oil soap, 

 and one quart of water. This is heated till the soap is dis- 

 solved, when one pint of kerosene oil is added, and the whole 

 agitated till a permanent mixture or emulsion is formed. The 

 agitation is easily secured by use of a force-pump pumping 

 the liquid with force back into the vessel holding it. I then 

 add water, so that there shall be kerosene in the proportion 

 of one to fifteen."— (Prof. A. J. Cook, in Bulletin 26 of the 

 Agricultural College, Michigan, U.S.A.) 



I give the above recipe first, because, being noted as a 

 satisfactory application for the Apple Aphis, it may be pre- 

 sumed the proportion of kerosene would not be enough to 

 injure ordinary bark ; but all experimenters should bear in 

 mind that the strength and amount of mineral oil used must 

 be well considered, and the same strength may not be safe on 

 all parts of young trees, or on all conditions of leafage. 



Another recipe is for " Kerosene Emulsion " of the ordinary 

 strength for general application, viz., kerosene or refined coal 

 oil, 1 pint; common laundry soap I- oz.; rain-water | pint. 

 The soap was boiled in the water till all was dissolved, then 

 the boiling soapsuds were poured into a watering-pot contain- 

 ing the kerosene, and churned with a garden-syringe until the 

 emulsion was complete. This generally takes about five 

 minutes, but sometimes longer. When this emulsion is 

 made, it can be bottled up for future use. When using it, 

 either as a wash for sponging trees or for spraying, it must 

 be diluted with nine times the quantity of water. Should the 

 oil in the emulsion after a time separate, it is well to warm it, 

 and by violently shaking the bottle it will again become fit for 

 use. In diluting the emulsion use warm water. See p. 14 of 

 ' Eeport of Entomologist and Botanist, Department of Agri- 

 culture, Canada,' 1887. 



The following recipe is one of the Department of Agri- 

 culture of the United States of America. In this the plan is 

 to add one gallon of water in which a quarter of a pound of 

 soft-soap (or any other coarse soap preferred) has been 

 dissolved, boiling or hot, to two gallons of petroleum or other 

 mineral oil. The mixture is then churned, as it were, together 

 by means of a spray-nozzled syringe or double-action pump 

 for ten minutes, by means of which the oil, soap, and water, 

 are so thoroughly combined that the mixture settles down 

 into a cream-like consistency, and does not, if the operation 

 has been properly performed, separate again. This is used 

 diluted with some three or four times its bulk of water for a 

 watering ; if required for a wash, at least nine times its bulk 

 is needed — that is, three gallons of "Emulsion," as it is 



