Sperma Ceti Pharm. Lond. & Edinb. Spermaceti, improperly so called: a species of fat; found in certain wales, particularly in their heads; artificially purified, by boiling with alkaline lye, to a snowy whiteness; and afterwards broken into flakes. It differs from the other animal fats, in not being dissoluble by alkalies or combinable with them into soap; and in riling almost totally in distillation, not in form of a fluid oil, but in that of a butyraceous matter reiembling, both in consistence and smell, the butter of wax. In long keeping, it is apt to turn yellow and rancid: the matter, very small in quantity, which has suffered this change, and which taints the reft, is found to have loft the dicriminating characters of the spermaceti; being dissoluble both by alkaline lye and by vinous spirits, so as to leave the remainder white and sweet as at fir ft.

This concrete, of a soft butyraceous taste and no remarkable smell, is given with advantage in tickling coughs, in dysenteric pains and erosions of the intestines, and in such cases in general as require the solids to be softened and relaxed, or acrimonious humours to be obtunded. It readily dissolves in oils, and unites by liquefaction with wax and resins; and in these forms is applied externally. For internal use, it may be dissolved in aqueous liquors into the form of an emulsion, by trituration with almonds, the yolk or white of an egg, and more elegantly by mucilages; or made into a lohoch with proper additions.