364) 0}i ihe Allotjs of Steel. 



which enabled us to transfer our operations from tlie labora- 

 tory of the chemist, to the furnace of the maker of cast steel. 



In making the alloys on a large scale, we were under the 

 necessity of I'emoving our opei-ations from London to a steel 

 furnace at Sheffield; and being prevented by other avocations 

 irom giving personal attendance, the superintendence of the 

 Avork was consequently intrusted to an intelligent and confi- 

 dential agent. To him the steel, together with the alloying 

 metals in the exact proportion, and in the most favourable 

 state ibr tiie purpose, was forwarded, with instructions to see 

 the whole of the metals, and nothing else, packed into the cru- 

 cible, and placed in the furnace, to attend to it while there, 

 and to sillier it to remain for some considerable time in a 

 state of thin fusion, previous to its being poiu'ed out into the 

 mould. The cast ingot was next, under the same superin- 

 tendence, taken to the tilting mill, where it was forged into 

 bars of a convenient size, at a temperature not higher than just 

 to render the metal sufliciently malleable under the tilt ham- 

 mer. When returned to us, it was subjected to examination 

 both mechanical and chemical, as well as compared with the 

 similar products of the laboratory. From the external appear- 

 ance, as well as from the texture of the part when broken by 

 the blow of the hammer, we were able to form a tolerably cor- 

 rect judgement as to its general merits ; the hardness, tough- 

 ness, and other properties, were farther proved by severe trials, 

 after being fashioned into some instrument, or tool, and pro- 

 perly hardened and tempered. 



It v.'ould prove tedious to enter into a detail of experiments 

 made in the Koyal Institution ; a brief notice of them will at 

 })resent be sufficient. After making imitations of various spe- 

 cim.ens of meteoric iron, by fusing together pure iron and 

 nickel, in proportions of 3 to 10 percent., we attem.pted mak- 

 ing an alloy of steel with silver, but failed, owing to a super- 

 abundance of the latter metal ; it was found, after very many 

 trials, that only the j^(j part of silver would combine with 

 steel, and wiien more was used a part of the silver was found 

 in the form of metallic dt\\\ lining the top and sides of the 

 crucible; the fused button ;:; elf was a mere mechanical mix- 

 ture of the two metals, globules of silver being pressed out 

 of the mass by contraction in cooling, and more of these glo- 

 bules being forced out by the hanuner in forging; and fur- 

 th.er, when the forged piece was examined, by dissecting it 

 with diluted sulphuric acid, threads or fibres of silver were 

 seen mixed with the steel, liaving something of the apj'>ear- 

 atice of steel and platina when united l)y welding: but when 

 the proportion of silver was only j^'ijt part, neither dew. glo- 

 bules 



