258 
SteeL 
hammer, upon a proper tooh The workman holds the 
vessel with his right hand with his small tongs, 7 ; and 
with his left hand, without tongs, taking care to turn it 
round continually. Sometimes he performs this opera- 
tion with a stroke of the hammer ; and the complete finish 
is made by cutting the edges with scissars, similar to those 
before described. 
The furnace made use of is a simple forge furnace, an$ 
the fuel is charcoal of fir, excited by wooden bellows. 
STEEL. 
Preliminary facts and observations . — I have already i 
.given some useful notices concerning charcoal. But X think i 
it right again to resume the subject, and to consider it in a t! 
point of view more strictly chemical. Xdo this, in the outset ! 
of the consideration of the manufacture of steel, because 
X consider steel, as pure iron, chemically united 
to pure charcoal. Pure charcoal, free from earth, 
ashes, water, oxygen, atmospheric air, or hydrogen, (the 
substances with which common charcoal even when well 
burnt, is usually contaminated) is called c arbon by the 
chemists, and is found naturally in its greatest purity in 
the diamond ; which however Mr. Davy has lately found 
to contain a very small proportion of earthy matter. 
Carbon then is contained in wood ; in stone coal ; in 
well burnt charcoal of wood ; in well burnt charcoal of 
pitcoal ; in animal substances and the charcoal of animal 
substances ; in the diamond ; in plumbago or black lead ; 
in the carbonic acid. The carbonic acid, is united in a 
solid state to chalk, marble, and limestone ; and frequent- 
