Iron • 
22S 
by Mr. Mushet in combining iron directly with the doses 
of charcoal requisite to produce its various sub-carburets, 
T Vth appeared to be the maximum . Of this, the follow- 
ing table, published by him in the 13th voh of the Philo* 
__ ___ ' 4 
sophical Magazine, will afford the necessary proof* 
Soft cast steel ------- -rbr 
i 
TUTS 
1 
US 
Common ditto » - - * - 
Same, but harder » 
Ditto, too hard for drawing - - 
White cast iron, (same as before called forge-frig ) ~ r 
Mottled cast iron (No. 2.) - * - 
Black cast iron (No. 1.) « *> - , \ 
5 O 
The first step in the process of decarbonization, accord- 
ing to the more common mode of operating, is to ex- 
pose the iron in a furnace, called by some a refinery , but 
by others, to distinguish it from one hereafter to be des- 
cribed, a run-out furnace. It consists of a vessel open 
at the top, imbedded in stone or brick work, about two 
feet three inches long, two feet wide, and ten inches deep* 
This is generally, in part, constructed of cast iron ; and, 
when so made, has an outer case about two or three inch- 
es distant from the inner one, which is constantly sup- 
lied with a stream of cold water to prevent the apparatus 
from melting. The iron to be decarbonized is placed in 
this receptacle, and kept in a continual state of fusion for 
three or four hours by the aid of a coke fire, which is heap- 
ed to a considerable height above the level. of the vessel, 
and extended proportionally on the hearth that surrounds 
it. The size of the hearth is mostly about three yards in 
length, and from two to three wide, and is completely co- 
vered by the funnel of the overhanging chimney. Bellows 
of considerable size are employed to carry on the process ; 
and the current of air which issues from them is directed 
immediately on the surfhce of the iron by one or more tu- 
yeres* These tuyeres are double, like the case, and con- 
