.SYA' \V1LLIAM SIEMENS, fi.R.S. 3! I 



In t/ie discussion of the Paper 



" ON THE MANUFACTURE AND USE OF SPIEGELEISEN," 

 By MB. GEO. J. SNELUS, 



DR. SIEMENS* said the Landore Works being producers of 

 spiegeleisen, he could, from his experience there, bear out nearly 

 all that had been said by the author of the paper. He agreed 

 with him that there was no great difficulty in producing spiegel, 

 as, indeed, all things were simple if they knew how to deal with 

 them, though up to that point they were difficult. At first there 

 had been a difficulty in getting the slag right, and according to 

 their experience the slag must be as basic matter as possible. They 

 had succeeded in making spiegel containing as much as from 18 

 to 20 per cent, of manganese, and they could vary it so as to make 

 it from 10 to 12 per cent., which was what was preferred for 

 common use, the richer spiegel being reserved for producing extra 

 mild steel. There was one point upon which he would like to ask 

 Mr. Riley to give a little more information, that was, why did 

 spiegeleisen never contain even a trace of sulphur ? As he under- 

 stood the paper, it was owing to the manganiferous slag having a 

 greater capacity for sulphur, but he (Dr. Siemens) thought that 

 that explanation was hardly sufficient for the extraordinary fact 

 that they did not find even a trace of sulphur in spiegeleisen. 

 As regarded phosphorus, it had been contended that it acted as a 

 substitute for carbon, and was rather a desirable constituent in 

 spiegeleisen, but he would much rather be without it, and not risk 

 the beneficial effect of phosphorus on the steel. Another interest- 

 ing point with respect to the use of spiegeleisen, was the nature of 

 its effect upon the steel ; was it that the manganese simply 

 deoxidised the iron, or was it that the manganese must be present 

 in a metallic state, in order to produce malleable steel ? He 

 inclined to the latter hypothesis, because his observations went to 

 prove that manganese was necessary in malleable steel, especially 

 if sulphur was present. Manganese seemed, in fact, to have a 



Excerpt Journal of the Iron and Steel Institute, 1874, pp. 84-86. 



