Between that time and 1770 he practised melting small pieces of blistered steel (iron bars which had been carbonised by smelting in charcoal) in closed clay crucibles. 威廉·亨利·杜利特.世纪发明.
Furnaces to hold the crucibles, and made of iron cylinders lined with fire brick, whereby the crucibles were subjected to greater heat, were also known. 威廉·亨利·杜利特.世纪发明.