84- Mr. D. Mushet on the Alloys of Iron and Copper, 



can be perceived, but a very considerable increase of hardness 

 may be observed. 



When copper is fused with y^^h of its weight of bar steel, 

 an ingot is obtained which outwardly resembles the former, 

 with the radiated linear crystallization less distinct. But the 

 fracture, which is hard and brittle, shows, by minute points of 

 copper, the commencement of an indisposition or inability to 

 further union, or alloy, between the two metals. 



Again, when ^th the weight of copper is added of steel, an 

 ingot is obtained which exhibits, when filed, a partially cop- 

 pery appearance, of a deep red on the lower, and steel bright 

 on the upper surface. The fracture displays a regular grain, 

 which indicates an intimate mixture of copper and iron, ap- 

 parently of greater strength than in the two former alloys. 



When 3^rd of copper is added to the steel, the former seems 

 to separate, and seeks in considerable quantities, in a soft and 

 malleable state, the lowest part of the crucible. The fracture 

 exhibits the copper in streaks and knots, indicating a decided 

 want of union*. 



White cast iron, which resembles steel in the quantity of 

 carbon which it contains, affords nearly the same result when 

 fused with similar portions of copper ; the alloy, however, 

 possesses less strength, and a greater tendency to disunion 

 when the proportion of copper is increased beyond g'oth. 



The union of copper with gray cast iron, if at all practica- 

 ble, must take place in very minute quantities ; for in fusing 

 5 per cent, of copper along with No. 1, or smooth-faced pig 

 iron, specks of deep red coloured copper were found upon 

 the lower surface of the ingot, and similar traces were dis- 

 cernible in the fracture. With y'^yth the copper became of a 

 deep red colour, separated in leaves, and attached itself to 

 the outside of the cast iron ; and when copper to the extent of 

 ]-th was tried, a solid button of copper was found beneath 

 the cast iron in the bottom of the crucible. 



From all I have learnt on this subject, I conclude that cop- 

 per unites with iron in proportion as the latter is free from 

 carbon; hence it would appear impossible to produce a mixed 

 metal, or alloy of copper and iron, by smelting in a blast fur- 

 nace, in contact with carbonaceous matter, an ore containing 

 both these metals. It is true that we have ores which, when 



* Steel, both English and Indian (or wootz), was alloyed with copper, in 

 the proportion of two per cent, of the latter, by Messrs. Stodart and Fara- 

 day, in their experiments on the Alloys of Steel; but of the value of this 

 alloy, they observe, " we have doubts." They did not attempt to produce 

 it in the large way. See Quart. Journ. of Science, vol. ix. p. 325, 329 ; and 

 Phil. Mag. vol. Ivi. pp. 31, 54; vol. Ix. p. 3/1. — Edit. 



