Crude iron, and steel of a uniform tex ture, consist therefore of a fusible combi nation of iron with the combustible sub stance of the coal, or something which is imparted from it, the crude iron differ ing from the steel simply in being over dosed with carbon, and less pure, on ac count of the admixture of metallic oxide, which can scarcely, perhaps, be avoided in the large process. It appears, there fore, that crude iron must pass through the state of steel, before it can become forged iron ; and, consequently, that the fabrication of steel from this last is a cir cuitous process, which can only be repaid by the absence of those unreduced parts which may exist in the crude iron. At some forges, however, where the ore, the flux, the fuel, and the management, are adapted to each other, the produce af fords steel, when duly refined. At other manufactories, the crude iron is either refined, or converted into steel, by run ning it into thin plates, which are strati fied with charcoal, and burned in a close furnace. In this way the metal is refined by degrees, without undergoing fusion ; and if the heat be raised to that of ce mentation, the iron will not only be re duced, but converted into steel. In the
forges of Carinthia, the grey crude iron is also converted either into soft iron, or steel, according to the management of a somewhat similar process. iron is fused in a large melting pot ; and a small and laying it by for a week or two, till a complete coat of rust is formed. A little oil is then applied, and the surface, being rubbed dry, is polished by means of a hard brush and a little bees-wax.
The yellow spots, called iron moulds, which are frequently occasioned by wash ing ink spots with soap, may in general be removed by lemon juice, or the oxalic or tartarous acids ; or by muriatic acid diluted with five or six parts of water, but this must be washed off in a minute or two. Ink spots may readily be remov ed by the same means. If the iron mould have remained so long, that the iron is very highly oxided, so as to be insoluble in the acid, a solution of an alkaline std. phuret may be applied, and, after this has been well washed off, the acid *ill remove the stain.