U. S. DEPARTMENT OF AGRICULTURE 
Vegetable oils are placed in three classes — drying, semidrying, and 
nondrying. Of these only the drying and semidrying oils were used, 
the drying oils being linseed oil, soy-bean oil, and Chinese wood 
oil, and the semidrying oils corn oil and cottonseed oil. Fish oil 
was the only animal oil used. Some of the properties of these oils 
and their drying qualities when applied as a thin film on any surface 
are here set forth. 
Linseed oil is obtained from the seeds of the flax plant, Linum 
usitatissimum, a native of central Asia, but cultivated in many parts 
of the world for the fiber, which forms linen, or the seed, from which 
the oil is obtained. The seeds contain from 36 to 42 per cent of oil, 
which is obtained from them by expression or extraction. It is of a 
golden-yellow color, dries rapidly on exposure to the air, and adheres 
closely to the surface beneath. 
Fish oil, sometimes known as . mossbunker oil, pogy oil, or white- 
fish oil, is obtained principally from menhaden, a shadlike clupeoid 
fish of the genus Brevoortia, very abundant on the North Atlantic 
coast of the United States. Light-pressed fish oil is obtained by 
steaming the fish and subjecting it to gentle pressure; the cheaper 
grades are extracted from the residues. The oil is yellow to brown 
in color and dries readily on exposure to the air, but adheres some- 
what less strongly than linseed oil to the surface beneath. The price 
is about 75 cents per gallon in barrel lots. 
Corn oil, known also as maize oil, is obtained from the germ of 
corn, after it has been separated in the manufacture of starch, or 
from the residues of corn obtained in the fermentation of alcohol. 
The oil from the former source is pale to golden yellow; that from 
the latter, reddish brown. Corn oil dries readily on exposure to the 
air, but does not adhere so closely to the surface beneath as does 
linseed oil or fish oil. Its price is about $1 per gallon in barrel lots. 
Soy-bean oil. sometimes known as soja oil or Chinese bean oil, is 
extracted from soybeans. It is pale yellow to brown and dries slowly 
on exposure to the air, forming a soft film. Its price is about $1.10 
per gallon in barrel lots. 
Chinese wood oil, known also as Tung oil, is imported from the 
Orient, is pale yellow to dark brown, and on exposure to the air dries 
more rapidly than linseed oil, but does not adhere strongly to the 
surface beneath. Its price is about $2.60 per gallon in barrel lots. 
Cottonseed oil is obtained from the seeds of the cotton plant, is 
pale yellow, and dries slowly on exposure to» the air, but does not 
adhere to the surface beneath quite so well as does corn oil. Its 
price is about $1.05 per gallon in barrel lots. 
As a preliminary test of the adhesiveness of sprays of arsenate 
of lead, each containing one of the six oils which have just been 
described, it seemed best to spray them on glass plates and observe 
their behavior after drying. Standard arsenate-of-lead mixture was 
used, successive portions of which contained one-half of 1 per cent and 
one-fourth of 1 per cent of each of the oils, making 12 different mix- 
tures, all successively sprayed on glass plates. A cylindrical sprayer 
of the compressed-air type was used, the material being agitated by 
an occasional shaking of the pump. All of the oils mix mechanically 
with the water and are distributed through it in very fine globules. 
It was found better to add the arsenate of lead before adding the oil; 
by doing so the latter remained for a longer time distributed through 
