S7/? lVILL!A.\f SIEMENS, f.R.S. 353 



In the discussion of the Paper 



ON THE SEPARATION" OF CARBON, SILICON, SUL- 

 PHUR, AND PHOSPHORUS in the REFINING and 

 PUDDLING FURNACES and in the, BESSEMER CONVERTER ; 

 with some Remarks on the MANUFACTURE AND DURABILITY OF 

 RAILWAY BARS," by Mr. I. LOWTHIAN BELL, M.P., F.R.S., 



and some further remarks regarding 



"THE PRODUCTION OF IRON AND STEEL BY DIRECT 

 PROCESS," by Mr. C. WILLIAM SIEMENS, D.C.L., F.R.S. 



THE PRESIDENT * (Mp,. C. "W. SIEMENS) said that perhaps he 

 might be permitted to explain a point to which Professor 

 Williamson had referred, as it might save time hereafter. 



Professor Williamson wished to know how it was that in 

 a rotative furnace the phosphorus did not go back to the 

 metal, seeing that the temperature must be as high as in a 

 puddling furnace. This question would give him the opportunity 

 of explaining the action as it took place in a rotative furnace. 

 Thirty hundredweight of material was introduced into the fur- 

 nace ; and heat was applied intense heat, if they liked to work 

 upon this mixture. At first the temperature of the mixture did 

 not rise, because the work that had to be done was carried on, as 

 it were, at its own temperature that of the reducing point of iron 

 ore. But as the deoxidation of the iron proceeded, the tempera- 

 ture would rise, and a point would be attained where metal would 

 become malleable ; but at this point the fluxing materials, which 

 had been mixed with the ore, would have commenced to be fluid, 

 and would form fusible slag which, immediately upon fusion, would 

 away from the mass, sinking to the bottom of the rotative 

 whereas the solid material formed on one side, and rolled 

 about until it went into balls. Hence, although the flame that 



* Excerpt Journal of the Iron and Steel Institute, 1877, pp. 389-395. 



VOL. I. A A 



