Manchester Memoirs, Vol. Ivii. (191 3), No. II. 25 



36% of iron, and had shown how to manufacture this 

 commercially, he would have been entitled to a patent for 

 his mode of producing it, and he denies his (Mushet's) 

 right to patent the sole use of manganiferrous pig-iron. 



In his earliest experiments, Bessemer avoided oxida- 

 tion of the metal in the only way that he knew how to, 

 namely, by practising a limited decarburization — that is, 

 the practice later followed in Sweden and Austria. Some 

 3'ears before his death, Bessemer was able to show, 

 through the finding of some of his old note-books, 

 that by reading a description of Heath's invention in 

 Ure's " Dictionary of Arts, Manufactures and Mines," he 

 knew that red-shortness could be cured by carburet of 

 manganese, and that he attempted to make carburet of 

 manganese. These experiments, which were prior to 

 Mushet's patents, led, after many delays and difficulties 

 to the manufacture of ferro-manganese by Henderson, in 

 Glasgow, at Bessemer's instigation. Meanwhile Mushet's 

 patent had rendered Bessemer the service of drawing his 

 attention to the fact that there existed a manganesian pig- 

 iron — an alloy of carbon, manganese and iron. Spiegel- 

 eisen was not an absolute essential to the Bessemer 

 process, although its ready availability removed, for a time, 

 the difficulties that would otherwise have existed prior to 

 the manufacture of other suitable manganiferrous com- 

 pounds in the blast furnace. 



Reviewing carefully all the evidence, it is impossible 

 to deny the fact that Mushet did Bessemer a great and 

 valuable service in drawing his attention to the utility to 

 him of the existence of spiegeleisen, famed for steel- 

 making on the Continent,"' but it is equally impossible to 



'^^ Mushet had experinienled with spiegel-iron ol)tainod from Rhenish 

 Prussia, and having a composition of 8 '5% manganese, carbon 5'25%, and 

 iron 86-25%, as far back as 1848 ; he does not refer to the fine exhibit of this 

 material in the German section of the Great Exhibition at the Crystal Palace 

 in 1851. 



