Circular 21 - Insecticides and Subsidiary R!aterials 47 
Linseed oil is a yellov/ish drying oil 
expressed or extracted from flaxseed. It is 
used extensively in paints, also in makimg 
printer's ink, linoleum, soap, and in medicine 
as a laxative. 
This oil is available in 8,000 gallon 
tanks, 375 to 400 pound barrels, and in 1 and 
5 gallon cans ranging in price from 10 to 12 
cents per pound. 
Available on contract: see Class 52, 
General Schedule of Supplies, Procurement 
Division, Treasury Department. 
LUBRICATING OIL 
Lubricating oil has limited use as an 
insecticide. A mixture of 20 parts lubricating 
oil (SAE 10) and 1 part of kerosene-pyrethruia 
concentrate lightly painted on window screens 
will keep out the flies knov.-n as eye gnats for 
several hours vAien these are troublesome. 
Lubricating oil is one of the higher 
boiling fractions of crude oil. The color 
varies considerably from one brand to another 
but is usually some shade of yellov/ish-brown 
or amber. It is obtainable in various degrees 
of viscosity. The SAE 10 mentioned is a very 
thin grade while increasingly heavy grades are 
SAS 20, 30, 40, 50, and 60. 
Caution : Lubricating oil will burn and 
oil-soaked rags left in poorly ventilated 
places may ignite by spontaneous combustion. 
