Crude cotton seed oil is a thick fluid of a reddish or dirty yellow color, and if left standing will deposit a slimy sediment. For years the cotton seed oil refiners encountered very great difficulty in disposing of this coloring matter, but this impediment is now overcome in the following manner. To an iron tank charged with ten tons of crude cotton seed oil, is added thirty hundred weight of caustic soda lye. Saponification ensues, and the coloring matter is precipitated. No argument can convince the impartial mind that an article so prepared is fit food for the human stomach. There are many other adulterants which are used in unison with cotton seed oil, such as sesame, palm nuts, hemp, cupra or sunflower, and a host of others of strange origin. It is not safe to say that these supposititious comestibles are always innocuous. Many an oil retains the subtle qualities of the plant which produced it, and it may be that obscure maladies which puzzle the doctor are not unfrequently caused by the detestable practice of supplying for the genuine article something which looks sufficiently like it to mislead, and, it may be, poison the hapless public. A simple and homely test for the detection of adulteration is the heating of oil until it smokes, in some small vessel. The smell of olive oil while suggestive of the kitchen and cookery is not at all disagreeable, while any counterfeit oil, and especially cotton seed oil, is exceedingly offensive to the nostrils. If placed in a refrigerator, pure olive oil will remain unchanged, or at most throw down a little palmatin, while adulterated oil will thicken and congeal. The persistent adulteration of olive oil will bear its legitimate fruit; the markets where the world has sought its supply heretofore will become discredited, their wares will no longer meet with ready sale in the face of free supplies of the pure article from California and Australia.
Gasparin makes some interesting calculations as to the consumption of oil in France. In Provence a laborer consumes an average of nine pounds per annum, and the same ratio holds good in Paris.
