109 
. 
Observations on Fron and Steel. 
BY JOSEPH COLLIER, 
READ NOVEMBER 18TH, 1796. 
After examining the works of different authors, 
who ‘have written on the subject of making iron 
and steel, I am persuaded that the accounts given 
by them of the necessary processes and operations 
are extremely imperfect. Chemists have examin- 
ed and described the various compound minerals 
containing iron with great accuracy, but have been 
less attentive to their reduction. This observation 
more particularly applies to steel, of the making-of 
which I have not seen any correct account. 
It is singular to observe, how very imperfectly 
the cementation of iron has been described by men 
of great eminence in the science of chemistry. Cit. 
Fourcroy states the length of time necessary for the 
cementation of iron to be about twelve hours; but 
it is difficult to discover whether he alludes to cast 
or to bar steel : for he says, that short bars of iron are 
‘to be put into an earthen ‘box with a cement, and 
closed up. Now steel is made from bars of iron 
of the usual length and thickness; but cast steel is 
made according to the process described. by Cit. 
Fourcroy, with this essential difference: the opera- 
tion is begun upon bar steel and not bar iron, 
