20 Farmers’ Bulletin 1223. 
be omitted. The quantity of insecticides must be estimated and the 
orders placed early in the year to avoid delay due to heavy sales and 
slow transportation. 
LUBRICATING OIL. 
All of the principal oil-refining companies market an oil suitable 
for this purpose. The cheapest and usually lightest grade of oil is re- 
quired. Its specific gravity is usually from 24° to 32° Baumé and its 
viscosity 200 or over. The present cost is from 38 cents to 50 cents per 
gallon, depending upon the quantity purchased. 
SOAP. 
For the sake of securing an article of known strength and purity, 
as well as reducing the cost, the soap should be made at home. A 
very satisfactory soap may be made of crude corn or cottonseed oil 
and caustic soda, after the following formula. Cottonseed oil may 
be purchased of any of the cotton oil refining companies. Off-grade 
refined oil can sometimes be purchased as cheaply as the crude oil 
and is highly satisfactory. The corn oil can be purchased of manu- 
facturers of corn products. The technical grade (78 per cent pure) 
of soda is satisfactory and can be purchased of wholesale drug 
houses. 
Soap ForMULA. 
Caustie™ Sodart 200 eas tear fee Se Ears at ae pounds._ 4 
D621 e's pee a eer ge CE eee Alene ee BON EA per ge eres eee gallon= sel 
CrUGELCOLNVOU. OT COLON RO) eee ee ee Gdo22225 2 
Directions for preparation.—Place the water in the mixer already 
described, sprinkle the soda in the water to avoid danger of an ex- 
plosion from suddenly generated heat, and rotate the agitator slowly. 
While still hot pour the oil slowly in, meanwhile churning as vigor- 
ously as possible without splashing. The heat developed by dissolv- 
ing the soda in the water is very necessary for the formation of the 
soap; therefore add the oil before the mixture begins to cool. The 
oil should be poured in a thin stream from a sprinkling can from 
which the cap has been removed, or slowly pumped in with a tin 
gasoline pump. Continue churning slowly until the mixture is of 
uniform color throughout and begins to thicken and the dasher to 
turn hard. Then pour into a clean barrel or other receptacle and 
cover for storage. Further batches may be poured directly upon the 
first. If properly made and stored in air-tight containers, this soap 
will keep for years. Evaporation should be prevented, otherwise the 
soap will become very hard. Galvanized-iron grain cans, with fitted 
lids, are excellent for storing the soap for a period of several months 
to a year. 
