Where one is afraid pure linseed oil may not be furnished, the following prescription furnished by the Entomological department of the Department of Agriculture may be employed :

Kerosene....... .................................... 2 gallons.

Common Soap or whale-oil soap................... 1/2 pound.

Water............................................... 1 gallon.

Heat the solution of soap and add it boiling hot to the kerosene. Churn the mixture by means of a force-pump and spray-nozzle for five or ten minutes. The emulsion, if perfect, forms a cream which thickens on cooling. Dilute one part, before using, with nine parts of cold water. The percentage of oil can be increased considerably without danger to the plant, and a stronger emulsion may be required in coping with some of the Aspidiotus scales.