58 On the Alloys of Steel. [1820. 



first, to ascertain whether any alloy could be artificially 

 formed, better, for the purpose of making cutting-instruments, 

 than steel in its purest state ; and secondly, whether any 

 such alloys would, under similar circumstances, prove less sus- 

 ceptible of oxidation ; new metallic combinations for reflecting 

 mirrors were also a collateral object of research. 



Such a series of experiments were not commenced without 

 anticipating considerable difficulties, but the facilities afforded 

 us in the laboratory of the Royal Institution, where they were 

 made, have obviated many of them. The subject was new, arid 

 opened into a large and interesting field. Almost an infinity 

 of different metallic combinations may be made, according to 

 the nature and relative proportions of the metals capable of 

 being alloyed. It never has been shown by experiment, whe- 

 ther pure iron, when combined with a minute portion of carbon, 

 constitutes the very best material for making edged tools ; or 

 whether any additional ingredient, such as the earths, or their 

 bases, or any other metallic matter, may not be advantageously 

 combined with the steel ; and, if so, what the materials are, and 

 what the proportion required to form the best alloy for this much 

 desired and most important purpose. This is confessedly a 

 subject of difficulty, requiring both time and patient investiga- 

 tion, and it will perhaps be admitted as some apology for the 

 very limited progress as yet made. 



By referring to the analysis of wootz, or Indian steel*, it will 

 be observed that only a minute portion of the earths alumina 

 and silex could be detected, these earths (or their bases) giving 

 to the wootz its peculiar character. Being satisfied as to the 

 constituent parts of this excellent steel, it was proposed to 

 attempt making such a combination, and with this view various 

 experiments were made. Many of them were fruitless : the 

 successful method was the following. Pure steel in small 

 pieces, and in some instances good iron mixed with charcoal 

 powder, were heated intensely for a long time ; in this way they 

 formed carburets, which possessed a very dark metallic grey 

 colour, something in appearance like the black ore of tellurium, 

 and highly crystalline. When broken, the facets of small but- 

 tons, not weighing more than 500 grains, were frequently above 



* Quarterly Journal of Science, vii. 288. 



