=Origin of Butterine.=--Prior to the Franco-Prussian war, or in 1871, fats were used almost exclusively for soap making and other manufacturing purposes, comparatively little of it being used for food purposes. During the siege of Paris a reward was offered to anyone who would find a substitute for butter. A French scientist reasoned as follows: Careful observation teaches that a cow that is fat and in good health makes better butter and more butter than one of the same quality that is poor and emaciated, hence it must follow the cream of the milk, or the “butter-fat,” is in reality nothing more or less than Nature’s surplus fat in the animal, and that in all cattle that are fed each day more than the requirements to build up the broken-down tissues a surplus fat is deposited. This fat, the chemist decided, was as much a natural butter as though it had been skimmed from milk, and starting on this theory originated the manufacture of oleomargarine. =Result of Investigation.=--The creating of this industry has meant millions of dollars to this country in returns that have been made from the sale of fats prepared into oil for manufacturing oleomargarine instead of being melted into tallow for soap making and other purposes. =Oleo Oil.=--Oleo oil is the name of one of the principal ingredients used in making oleomargarine, or imitation butter. The fat is put through a hasher, which thoroughly disintegrates it, cutting the tissue so that the oil is made free when heated. =Oleo Fats.=--The fats used for the manufacture of oleo oil are usually all the fats removed when the animal is slaughtered, including the “caul” fat or that fat surrounding the “omentum”; the ruffle fat, which is that fat surrounding the intestines, and to which the “runners” or round gut is attached; the heart casing, and fats attached. =Selection and Care.=--It is reasonable to suppose that all of these fats are of the same quality, but in the handling of this, during the course of slaughtering and treatment thereof, some of it necessarily becomes unfit for oleo oil purposes, and is used in tallow. The amount used for tallow is regulated by the care and intelligence of the men in charge, and if properly handled a very small percentage of the fat in the animal should find its way to the tank house, as it nets much better results when put into oleo oil, as will be noted from the tests hereafter submitted.