Cast Steel. 
371 
allowed the term, from that peculiar to blistered steel* 
through all those breaks peculiar to the respective qualities 
of crude iron ; and may at last pass into the state of a car- 
buret of iron totally different in its properties and appear- 
ance from either steel or crude iron. This process may 
be carried on to the utter exclusion of atmospheric air ; 
and here, if the process is stopped in its proper stages, 
will be found all the various qualities of crude iron 
formed without perfect fusion, where we cannot conceive 
oxygen to have existed. 
I am aware of adducing circumstances from these ex- 
periments, at variance with the present received opinions 
upon the constituent parts of cast iron, and also in oppo- 
sition to principles which I have formerly laid down. I 
wish not the present hints to be considered as assertions. 
As irreconcileable in some degree with former opinions, 
I wish they may lead to an ample investigation of the 
subject. The distinction hitherto made betwixt crude 
iron and steel, particularly by the French chemists, has 
been, that crude iron was the metal imperfectly reduced, 
but that the latter was iron perfectly reduced, combined 
with a small portion of carbon. The fact, however, of 
malleable iron passing into the state of fine crude iron 
without the contact of an oxygenous body, puts it upon 
a similar footing with steel, only altered by a greater com- 
parative quantity of carbon. This reduces us to the ne- 
cessity of drawing one of the two following Conclusions : 
that steel is, equally as crude iron, a combination of iron, 
carbon, and oxygen ; or, that crude iron differs from steel 
only in the proportion of the carbon with which it is satu- 
rated. 
Exp . VII. Swedish bar iron - grs. 1174 
Charcoal ~th part, or 78 grs. 
A fusion was obtained from this mixture, after 
which there remained only a small portion of char- 
