(From crucio, to torment). Also called tigillum, catinus fusorius,albot,alkczoal, or crucible.

It is an earthen vessel, made for enduring the greatest degree of heat, generally wider above than below, and of a round or triangular figure. Calcined bones arc equal, if not superior, to any other materials for making them; some are made of equal parts of the best potter's clay dried, of a plumose alum, and of bastard talc, finely powdered, formed into a paste with whey, and then baked as other pottery. Chalk cut into the form of a crucible, then steeped in linseed oil for twenty-four hours, answers many purposes very- well: some use the powder of common tiles, and an equal quantity of chalk: these are mixed with linseed oil, and then baked. They may be either made of earth, black lead, forged iron, or platina; Chaptal says, they ought to support the strongest heat without melting, and be capable of resisting the attacks of all such agents as are exposed to heat in vessels of this kind. Those crucibles which possess the greatest degree of perfection arc made in Hesse, or Holland. Those made of platina unite the most excellent properties. They are nearly infusible, and at the same time indestructible by fire. M. Achard, and M. Morveau, have made them by first fusing platina with arsenic, which at first remains brittle; but in proportion as the arsenic is driven off by the continuance of heat, it becomes more ductile. These chemists, by melting it a second time in moulds, formed crucibles. Platina has been lately found more manageable, and various chemical vessels of this metal are now commonly met with. Various other materials, and modes of combining them, may be seen in Pott's Dissertation on Crucibles, and in the Dictionary of Chemistry. Chaptal's and Lavoisier's Elements of Chemistry.