SPERMACETI is found in the head of the Physeter macrocephalus, a species of whale ; it is obtained in an unctuous mass, from which oil is obtained by ex pression. Spermaceti is also found in other cetaceous 'fishes, and in other parts of the body, mixed with the oil. It is a fine white substance, of a crystallized tex ture, very brittle, and has little taste or smell. It crystallizes in the form of shin ing silvery plates. It melts at the tem perature of 112°. With a greater heat it may be distilled without change ; but, by repeated distillation, it is decompos ed, and partly converted into a brown acid liquid. It is soluble in boiling :deo hol, but it separates when the solution cools. It is also soluble in ether, both cold and hot. In the hot solution it con cretes on cooling into asolid mass. Sper maceti is scarcely at all soluble in the acids. It combines readily with the pure alkalies, with sulphur, and with the fixed oils. By exposure to the air it becomes rancid. The uses of spermaceti are well known, and particularly in the manufac ture of candles. Spermaceti differs chiefly from oil, by its solubility in alco hol and ether. According to Dr. Bostock, it requires 150 times its weight of al cohol, boiling hot, to dissolve it, and as the fluid cools, the spermaceti precipitates.
Spermaceti candles are of modern manufacture : they are made smooth, with a fine gloss, free from rings and scars, superior to the finest wax•candles in colour and lustre ; and, when genuine, leave no spot or stain off the finest silk, cloth or linen. A method has been
lately proposed by Dr. Smith Gibbes, of Magdalen College, Oxford, to convert animal muscle into a substance much re sembling spermaceti. The process is re markably simple : nothing more is ne cessary than to take a dead carcase and expose it to a stream of running water : it will in a short time be changed to a mass of fatty matter., To remove the offensive smell, a quantity of nitrous acid may then be poured upon it, which, unit ing with the fetid matter, the fat is sepa rated in a pure state. This acid indeed turns it yellow, but it may be rendered white and pure by the action of the oxy genated muriatic acid. Dr. Gibbes brought about the same change in a much shorter time. He took three lean pieces of mut ton, and poured on them the three mine ral acids, and he perceived, that at the end of three days each was much altered; that in the nitrous acid was much soften ed, and, on separating the acid from it, he found it to be exactly the same with that which he had before got from the water ; that in the muriatic acid was not in that time so much altered ; the vitriolic acid had turned the other black. See the ar ticle ADIPOCIRE.