Iron . 
229 
l which have been premised, that, in order to procure one 
ton of it, five-and-thirty hundred weight of forge-pig is 
previously required. 
Two other modes of operating are at present in use; 
one of which omits the puddling , and the other that part of 
the foregoing process that concerns the fabrication of 
blooms . In the former, iron is exposed to the heat of a 
charcoal fire, in a species of furnace precisely similar to 
the one before described as a refinery , or run-out -furnace ; 
and is continued in that situation, until the metal is 
thought to be sufficiently decarbonized. It is very fre- 
quently stirred during the operation ; and when brought 
into nature , (to use the technicle expression) is collected 
into masses, and removed by tongs under a large hammer, 
denominated, as applied to this particular use, a stamping 
hammer , where it is beaten into cakes, which are after- 
wards broken up, and treated in the balling furnace as be- 
fore described. This is the old mode of working, and 
the iron obtained from it is by many conceived to be of 
very superior quality. The heat produced is considera- 
bly inferior to that afforded by coke in the run-out fur- 
nace , and the iron is less surrounded by the fuel than in 
the case just mentioned. The present charcoal fire is 
properly a refinery , and not the one which is used merely 
as a preliminary to the process of puddling. Here the bu- 
siness of decarbonization is at once completed ; and the 
resulting metal is in the same state of purity as that yield- 
ed from the rollers, after it has been puddled by the other 
method. Balling and blooming follow in regular succes- 
sion, and plates or bars are produced exactly as before. 
According to the second mode of treatment in which 
blooming is omitted, the masses obtained from the hailing 
furnace are reduced under the hammer into the form of 
solid, cubical blocks ; and when their temperature is too 
much lowered to be capable of any farther working, they 
