A/A' WILUAM SIEMENS, F.R.S. 255 



obtained, in reference to the remarks made by Mr. Cowper, 

 Mr. Kolm, and Mr. Hackney ; Mr. Kohn said the silicon might 

 burn out on the surface of the melted metal, but he thought that 

 tin- experiments he had produced clearly indicated that both the 

 silicon and the carbon in the cast metal were oxidized by the 

 oxygen contained in the fettling. He begged to say that he had 

 not the slightest idea of suggesting that pig iron containing large 

 quantities of silicon was preferable ; he preferred the best, as 

 every ironmaster did, but had given the effects of a furnace on a 

 bad sample of iron as a severe test of its powers. There was no 

 doubt that the practical improvement in the quality of the iron 

 produced in his furnace was due, as Mr. Cowper had stated, partly 

 to a mechanical cause and partly to a chemical one, for the purer 

 flame of the furnace did far less injury to the iron, and the higher 

 temperature at which the metal was balled up without being 

 burned, caused the cinder to be so much more fluid, as to run out 

 better from the iron when squeezed, hammered, or rolled, thus 

 excluding more thoroughly those bad welds, " blacks " and 

 " greys," so plentiful in ordinary iron. 



In the discussion of the Paper, and the Supplementary Paper, 



"ON THE FURTHER UTILISATION OF THE WASTE 

 GAS FROM BLAST FURNACES, AND THE ECONOMY 

 OF COKE DUE TO INCREASED CAPACITY OF 

 FURNACE," by MR. CHAELES COCHRANE, of Dudley, 



MR. C. W. SIEMENS* said he had listened with great pleasure 

 to the paper, combining as it did practical experience with theo- 

 retical considerations ; and as regarded the chemical part of the 

 question the arguments advanced seemed to be based upon correct 



* Excerpt Minutes of Proceedings of the Institution of Mechanical Engineers, 

 1869, pp. 33-36, 39, 42-43, 62-68. 



