142 THE ADDRESSES, LECTURES, ETC., OF 



old Dowlais iron rails converted into steel at my Experimental 

 Steel "Works at Birmingham, which was rolled into rails by Sir 

 John Brown & Co. ; these have been down ever since that time at 

 Paddington, subjected to great wear and tear. 



The manufacture of steel, both by the Bessemer and the open- 

 hearth processes, is much facilitated by the use of ferro-manganese. 

 This material was introduced into the market in 1868, by Mr. 

 Henderson, of Glasgow. It was produced successfully by charging 

 carbonate or oxide of manganese, and manganiferous iron ore 

 intimately mixed with carbonaceous matter upon the open hearth 

 of a Siemens furnace with a carbonaceous lining ; but the demand 

 for this material was not sufficient to render the manufacture 

 profitable at that time, and it was not until the year 1875 that it 

 was re-introduced into the market by the Terrenoire Company. 



Manganese, when added in a proportion of "5 per cent., or more, 

 to steel or ingot metal, containing only from *15 to "20 per cent, 

 of carbon, has the effect of removing red-shortness, and of making 

 it extremely malleable both in the heated and cold conditions. 

 In using spiegeleisen containing only from 10 to 15 per cent, of 

 metallic manganese, it is impossible to supply the amount neces- 

 sary to produce this malleability without adding, at the same time, 

 such a percentage of carbon as would produce a hard metal. The 

 use of ferro-manganese enables us to overcome this difficulty, and 

 greatly facilitates the production of a metal so malleable and with 

 so little carbon, as to remain practically unaffected in its temper 

 when plunged red-hot into water. 



Another result produced by the use of manganese without 

 carbon, upon mild steel or ingot metal, is to neutralize the objec- 

 tionable effect of phosphorus, so long as the latter does not exceed 

 the limit of "25 per cent. This metal, in which phosphorus may 

 be said to take the place of carbon, presents a large specular 

 fracture, and is, contrary to what might have been expected, 

 extremely ductile when cold. 



Iron when in the fluid condition can be alloyed with other 

 metals, and some of the compounds thus formed are known to 

 possess very remarkable properties. Thus, iron combined with 

 3 per cent, of tungsten and - 8 per cent, of carbon, yields a metal 

 which can be worked like ordinary steel, but which, when hardened, 

 retains magnetism to a very remarkable degree, a property which 



