SPERMACETI, a white flaky substance, prepared from the brain of a species of whale called physeter microps. See PHYSETER.
One of these fishes affords some tuns of brains; which are first grossly freed from the oil by draining and pressing, and afterwards more perfectly purified by steeping them in a ley of alkaline salt and quick-lime, which dissolves the remains of the oily matter into a saponaceous liquid. The brains being then washed with water, appear of a silver whiteness; and nothing more is required to complete the preparation than to cut them in shivers with wooden knives, and spreading them abroad to dry. Such is the simple process by which this profitable commodity is prepared. It has been said that spermacet is a natural concrete, found floating on the surface of the northern seas; but this is plainly a false report, perhaps calculated to prevent inquiry into the manner of its preparation. Good spermacet is in fine white flakes, glossy and semitransparent, soft and unctuous to the touch, yet dry and easily friable; in taste somewhat like butter; of a faint smell like that of tallow. It is apt, in keeping, if not carefully secured from the air, to grow yellowish, and contract a rancid fishy smell. The more perfectly it has been purified at first, the less susceptible it is of these alterations; and after it has been changed, it may be rendered white and sweet again, by steeping it afresh in a ley of alkaline salt and quick-lime. It melts in a small degree of heat, and congeals again as it cools. Laid on burning coals, it emits a fetid smell like that of the snuff of a candle. The contact of flame does not set it on fire, but with a wick it burns equally with common tallow-candles. In distillation it totally arises, leaving no coal or caput mortuum behind. From four ounces were obtained three ounces and a half of oil, and a dram and a half of phlegm; the other two drams and a half having been
wasted or dissipated in the process. The oil is not a brown or black fetid empyreumatic one, like those of other animal substances, but clear, yellowish, of a butyraceous consistence, in smell like oil of wax, like which also it coagulates in the cold. Rectified spirit of wine, digested and boiled with spermacet, takes up about half a dram out of half an ounce: greatest part settles to the bottom, and the finer particles float in the liquor, in appearance like flowers of benzoine. Water long digested or boiled with it extracts nothing. By grinding it with sugar or almonds, it becomes miscible with water, but not near so perfectly as the vegetable resins do by the same treatment: on standing for a little time, the spermacet separates and floats on the surface. Yolks of eggs unite it more thoroughly with watery liquors; but when dissolved by these also, it soon separates and falls to the bottom. Even caustic alkaline ley does not dissolve nor unite with it into soap, as it does with all other fats; and hence the use of this ley in its preparation and purification. It mingles sufficiently with oils, fats, balsams, resins, butter, wax, &c.