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On the Application of the Hot Blast, in the Manufacture of Cast- 

 iron. By Thomas Clark, M. D., Professor of Chemistry in 

 Marischal College, Aberdeen. 



(Read 16th March 1835J 



Among persons interesting themselves in the progress of Bri- 

 tish manufactures, it can scarce fail to be known, that Mr Neil- 

 son of Glasgow, manager of the Gas Works in that city, has taken 

 out a patent for an important improvement in the working of 

 such furnaces as, in the language of the patent, " are supplied 

 with air by means of bellows, or other blowing apparatus." In 

 Scotland, Mr Neilson's invention has been extensively applied 

 to the making of cast-iron, insomuch that there is only one 

 Scotch iron-work where the invention is not in use, and in that 

 work, apparatus is under construction to put the invention into 

 operation. Apart from the obvious importance of any consider- 

 able improvement in the manufacture of so valuable a product as 

 cast-iron, the invention of Mr Neilson would merit attention, 

 were it only for the singular extent of the improvement effected, 

 compared with the apparent simplicity — I had almost said 

 inadequacy — of the means employed. Having therefore, by the 

 liberality of Mr Dunlop, proprietor of the Clyde Iron- Works, 

 where Mr Neilson's invention was first put into operation, ob- 

 tained full and free access to all information regarding the results 

 of trials of the invention in those works, on the large scale of 

 manufacture, I cannot help thinking that an authentic notice of 

 these results, together with an attempt to explain the cause of 

 them, will prove acceptable to the Royal Society of Edinburgh. 

 And that these results, as well as the cause of them, may be set 

 forth with clearness, I shall advert, 



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