22 PRELIMINARY NOTICE ON THE 



" broad and 7 iaches in depth, is built up in fire-brick, forming in fact a 

 " kind of large vertical muffle or retort. 



" This is entirely surrounded on all sides by the flues or chimney of the 

 " furnace. When in operation, this muffle or retort is filled with a charge 

 " of ore and coal both finely broken, and carefiiUy mixed up together, in 

 " the proportion of 20 to 25 per cent, of coal to 75 to 80 per cent, of ore.* 



" The heated gases from' the furnace playing round it raise the temper- 



" ature of its contents sufficiently to induce com- 

 Mode of working. 



" bustion of the carbonaceous matter, which com- 



" bustion is carried on slowly at the expense of the oxygen of the ore. 



" When the ore is sufficiently deoxidised, it is discharged from the bottom 



" of the muffle as required into the welding furnace, where the heat is 



" considerably increased, and the iron is readily worked into balls, and 



" thence taken to the hammer in the ordinary way. 



'^ The iron by this process cannot be said to be puddled, as the ore 

 " never really melts, but having first been deoxidised in a close chamber, 

 " is simply welded together in what the patentee of the process calls his 

 " ore-welding" furnace. He appears to think that the great merit of 

 " the process lies in the use of the closed chamber, in which the iron is 

 " perfectly protected from the wasting efiect of the flames and gases of 

 " the furnace during the process of deoxidation, which would otherwise, 

 " as they always do, oxidise and slag the ore : the probable reason why all 

 " attempts to work the ore in open chambers have failed. 



" The temperature at which the deoxidising action is carried on is not 

 " sufficiently high to cause the iron to combine 



Deoxidation at lower . • i r 



temperature ensuring " either with the carbou of the fuel or with any of 



greater purity. -l . i_ 



" the impurities, as silica, phosphorus, &c., which 



" are always found in common cast iron. 



" The balls were drawn from the furnace for " tilting" every half houf> 



" their size depending on the quality and yield of the ores used." 



* The muffle referred to by ProfesBor Wilson h«ld a charge of 12 cwt. 



