408 Scientific Intelligence. 
oxygen in the atmospheric air combines with the carbon contained in the 
iron, producing carbonic acid gas, and at the same time evolving a pow- 
erful heat. 
through the crude iron has been entirely consumed. The temperature, 
however, is so high that the chemically combined carbon now begins to 
separate from the metal, as is at once indicated by an immense increase 
or six minutes, all further appearance of it ceases, when a steady and 
werful flame replaces the shower of sparks and cinder which always 
accompanies the boil. 
earthy bases that are associated with the iron. The violent ebullition 
which is going on mixes most intimately the scoria and the metal, every 
part of which is thus brought in contact with the fluid oxyd, which will 
thus wash and cleanse the metal most thoroughly from the silica and 
other earthy bases which are combined with 2 iron, while the sulphur 
and other volatile matters which cling so tenaciously to iron at or i 
e loss in weight of crude iron, during its conversion into an ingot 
of malleable iron, was found on a mean of four experiments to be 124 
per cent, to which will have to be added the loss of metal in the finish- 
ing rolls. This will make the entire loss probably not less than 18 pet 
cent, instead of about 28 per cent., which is the loss on the present sys 
tem. A large portion of this metal, however, is recoverable by treating 
out of the furnace dur 
easily recovered. I have before mentioned that after the boil 
rfu 4 
soon as this diminution of flame is a parent, the workman well a 
. t, 
know that the process is completed, and that, the crude iron has been — 
Pees 
