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clouet’s method of making cast steel.

ter, ascertaining by experiments that less hidrogen gas is disen-gaged during the solution of steel in diluted sulphuric acid, thanduring the solution of iron in the same acid ; and that during thesolution of the steel, carbon is precipitated in the form of plum-bago. Morveau has justly observed that it is pure carbon, notits oxid that is present in steel, and to this its great hardnessmay be ascribed. Bergman further found, that some specimensof steel contained manganese and silex; and Vauquelin haslikewise discovered the existence of this earth, and of phosphorus,in several kinds of steel which he analyzed.

CLOUET’s METHOD OF MAKING CAST STEEL.

A new method of preparing cast steel has been lately an-nounced in France by Clouet. His process is the following:Take small pieces of iron and place them in a crucible, with amixture of carbonate of lime and the earth of Hessian crucibles;six parts of the carbonate of lime and six of this earth must beemployed for twenty parts of the iron. The matters are to be sodisposed, that after fusion, the iron must be completely coveredby them, to prevent it from coming into contact with the exter-nal air. The mixture is then to be gradually heated and at lastexposed to a heat capable of melting iron. If the fire be wellkept up, an hour will generally be sufficient to convert twopounds of iron into excellent and exceedingly hard steel capableof being forged; an advantage not possessed by steel made in thecommon manner.*

Metallurgy therefore comprehends three arts relative to iron,namely, its first fusion into crude iron; the change of this intobar-iron; and its conversion into steel.

The cause of the difference between crude iron, malleableiron, and steel, consists partly in this; that this metal may still

Phil, Mag. vol. II. p. 219.