VOL. LXXXV.] PHILOSOPHICAL TRANSACTIONS. 583 



stance was ignited to whiteness, and then quenched in a large bulk of cold water. 

 It was rendered much harder than before, so that a good file rubbed off very 

 little. I cannot however from this experiment determine whether wootz is sus- 

 ceptible of a greater, or so great a degree of hardness as some kinds of steel 

 used by the English artists, (f ) The piece (§ 3. e) was ignited in a close vessel, 

 and let cool in the ashes of the fuel. It became much less hard, but I never 

 could by annealing bring down the temper to the degree of any of our steels: 

 on which account it is far more difficult to forge. The interior parts of a thick 

 piece of wootz could scarcely be softened at all by armealing. 



(g) A piece of the substance, about 300 grs. in weight (wrapped in paper to 

 afford carbon enough to prevent oxidation, without super-saturating the metal 

 with carbon) was exposed in a close vessel for above an hour to a pretty consi- 

 derable fire. On cooling, the substance was found to have retained its form, but 

 it was of a slate-blue colour, and many round particles as large as pins heads ad- 

 hered to its surface, as if matter had oozed out by melting. The degree of fire, 

 indicated by Wedgwood's pyrometer, was 140°. A piece of our steel, which 

 had been a part of a file, was exposed in a similar manner, but to rather more 

 fire. It retained its form, and its surface remained smooth. A piece of crude, 

 or cast iron, by exposure to this degree of fire, under the circumstances just 

 mentioned, was fused: but in a temperature of about 120° its surfjice became 

 covered with a number of smooth roundish masses, as if fusion had begun. 



(h) 300 grs. of wootz were exposed as in the former experiment, but to a 

 fiercer fire, in my forge. The temperature was 148°; which is 23° more than 

 Mr. Wedgwood states he could produce in a common smith's forge. My forge 

 is moveable : the fuel is contained in a pan of cast iron lined with fire-bricks, as 

 proposed by Mr. More: the bellows are only of the 22 inch size. In this fire 

 the substance was melted with the loss of a few grains in weight. The surface 

 was quite smooth. It broke under the hammer like cast steel. It received as 

 fine a polish as that which had not been melted. Under a lens the polished surface 

 appeared quite uniform and close, with a few pores at equal distances. The 

 polished unmelted wootz had still fewer pores, and at unequal distances, but with 

 several fissures. Its grain, in the opinion of Mr. Stodart, was like that of cast 

 steel of the best quality; consequently it was uniform and rather close. Its spe- 

 cific gravity, as already stated, was about 7-200. 



500 grs. of steel wire melted under the circumstances just mentioned. The 

 mass which had been fused was fractured in the same manner, and had the same 

 kind of grain, as wootz which had been melted. I did not always succeed in 

 meltmg wootz and steel, though the fire denoted by the pyrometer was of the 

 same, or a higher temperature than that in which at other times they were 



