Sir T. Frankland on Welding Cast Steel. 297 
hazard of running under the hammer ? A few experiments de- 
cided the question ; for the fact is, that cast steel in a white 
heat, and iron in a welding heat, unite completely. 
It must not be denied that considerable nicety is required in 
giving a proper heat to the steel ; for on applying it to the 
iron it receives an increase of heat, and will sometimes run 
on that increase, though it would have borne the hammer in 
that state in which it was taken from the fire. 
I need scarcely observe, that when this process is intended, 
the steel and iron must be heated separately, and the union 
of the parts proposed to be joined effected at a single heat. 
In case of a considerable length of work being required, a 
suitable thickness must be united, and afterwards drawn out, 
as is practised in forging reap-hooks, &c. 
The steel on which my experiments have been made are 
Walker's of Rotherham, and Huntsman's, between which 
I discover no difference ; and though there may be some 
trifling variation in the flux used for melting, they are pro- 
bably the same in essentials. 
December, 1794. 
