502 
COTTON SEEDS. 
rollers, converting it into meal; the meal is put into a large 
vessel heated by steam, to render the oil more fluid, and then 
is put between iron plates, which are forced together by 
hydraulic pressure, which presses out nearly all the oil and 
some mucilage. About eight per cent, of oil is left, which 
cannot be removed except by solvents. This oil, as then 
obtained, is of a handsome dark wine colour and sweet taste. 
This then undergoes the purifying and bleaching process, 
which is kept a secret by the manufacturers. 
The purified oil is either a golden yellow or white colour. 
An oil is also produced by chilling the purified oil, and ex¬ 
pressing, to obtain a variety almost free from stearine, called 
by the manufacturers (( winter oil,” from the fact that cold 
will not thicken it. 
This oil is used extensively in the arts, chiefly to adul¬ 
terate and substitute higher-priced oils. Cheap paints are 
ground in it, and it is used to a certain extent to adulterate 
linseed oil; but being a non-drying oil, only a small per¬ 
centage could be used. 
It is also used for adulterating sperm oil for burning, and 
for mixing with lard oil. The most practical way to detect 
these is to heat the suspected oil with distilled water; sepa¬ 
rate the water and add a solution of subacetate of lead. If 
it contained cotton-seed oil, a white precipitate will be formed, 
on account of the presence of mucilage, which is always 
found in this oil. If the sperm or lard oil is pure, it would be 
indicated by the absence of any milkiness. 
It is also used to adulterate olive oil, and chemistry has 
found no practical mode by which they can be definitely dis¬ 
tinguished apart. 
A soap has been made of the residue left after refining. It 
is of a more or less dark brown colour, and disagreeable 
smell. It is used in the laundry, and sells from three to 
seven cents a pound, according to quality. It was also 
attempted to make a soap from the white oil. This, when 
first manufactured, is of a handsome white colour, but after 
standing some length of time it becomes dark, and finally 
almost black. It is not made now. 
It is used to the amount of ten per cent, in making fancy 
soaps, to give them a good lather, for which the oil is said to 
be the best known ; but even in this small amount the odour 
of the rancid oil can be detected. 
The hulls are used for fuel in the factory, and the greater 
part of the cake-meal was sent to Europe, the farmers of 
this country, at that time, not being generally acquainted with 
its properties. It sold for about thirty dollars a ton. 
