\\-lI.I.l.\M SfEMENS, F.R.S. 141 



was my esteemed friend, the late M. Leehatelier, the Inspect Hir- 

 (n'-iK-nil des Mines), succeeded, in 18(i5 and 18GO, in producing 

 steel upon the open hearth, they did not persevere sufficiently to 

 attain commercial results ; and it was not until after I had esta- 

 blished experimental steel works at Birmingham, that I was 

 enabled to combat in detail the various difficulties which at one 

 time looked well-nigh insuperable. 



Whilst thus engaged, Messrs. Pierre and Emile Martin, of 

 Sireuil, who had obtained licences for furnaces to melt steel both 

 in pots and on the open hearth, succeeded, after a short period of 

 experimenting, in introducing into the market open-hearth steel 

 of excellent quality. 



Messrs. Martin gave their attention to the production of steel by 

 the dissolution of wrought iron and steel scrap in a bath of pig 

 metal, whilst my own efforts were more especially directed to the 

 production of steel by the use of pig metal and iron ores, either in 

 the raw state, or in a more or less reduced condition, which latter 

 process is the one mostly employed in this country. 



One of the advantages that may be claimed for the open-hearth 

 process consists in its not being dependent upon a limited time 

 for its results. The heat of the furnace is such that the fluid bath 

 of metal, after being reduced to the lowest point of carburization, 

 may be maintained in that condition for any reasonable length of 

 time, during which samples can be taken and tested, and additions 

 either of pig metal, of wrought scrap, spongy metal, or ore, may 

 be made to it so as to adjust the metal to the desired temper. 

 The requisite proportion of spiegeleisen, or ferro-manganese, is 

 then added in the solid condition, and the result is a bath of 

 metal, the precise chemical condition of which is known, and 

 which has the advantage, if properly managed, of being what is 

 technically called " dead melted." This circumstance renders it 

 applicable for certain purposes for which pot steel has hitherto 

 been mostly employed. 



The purpose to which the open-hearth process is more especially 

 applicable is for the conversion of scrap steel, and iron of even' 

 description into steel or ingot metal, and it is now used, indeed, 

 to a large extent for the conversion into steel of old iron rails. 

 The wearing qualities of these converted rails have been under test 

 since 1867, when the Great Western Railway Company had some 



