A/A' WILLIAM SIEMENS, F.R.S. 



251 



proved decidedly superior to that from the ordinary furnace, being 

 what is technically called " best best " in the one, and " best" in 

 (lit; other case, from the same pig. 



The economy of fuel was also greatly in favour of the gas furnace, 

 but could not be accurately ascertained because some mill furnaces 

 were worked from the same set of producers. Still, judging from 

 the experience of several years, in the working of regenerative gas 

 furnaces as re-heating or mill furnaces, and as glass furnaces, the 

 saving of fuel in puddling cannot be less than 40 to 50 per cent, 

 in quantity, while a much cheaper quality may be used. 



The consumption of " fettling " was, however, greater in the gas 

 furnace, and the superior yield was naturally attributed by the forge 

 managers to that cause, although the writer held a different opinion. 



The gas furnace, however, had not been provided with water 

 bridges, these were subsequently added, and the furnace put to 

 work again in February last, since which time it has been worked 

 continuously. 



The result of the water bridges has been that the amount of 

 "fettling" required is reduced to an ordinary proportion, the 

 average quantity of red ore used being l)2'G Ibs. per charge, be- 

 sides the usual allowance of bull dog, while the yield per charge of 

 483*3 Ibs. of grey forge pig has been increased to 485 Ibs. of 

 puddled bar, as shown by the following return of a series of eighty 

 consecutive charges in June last : 



TABLE 111. 

 EEGENERATIVE GAS FURNACE. 



proving that the yield of puddled bar slightly exceeds the charge of 

 pig metal (representing a saving of fully 12 per cent, over the 

 ordinary furnace), while the superiority of quality in favour of the 

 gas furnace is fully maintained. 



It is also worthy of remark that these results are obtained regu- 



