the workman. Peter Onions of
Merthyr Tydvil, in 1783, carried the manufacture a stage further, as
described by him in his patent of that year. Having charged his
furnace ("bound with iron work and well annealed") with pig or fused
cast iron from the smelting furnace, it was closed up and the doors
were luted with sand. The fire was urged by a blast admitted
underneath, apparently for the purpose of keeping up the combustion of
the fuel on the grate. Thus Onions' furnace was of the nature of a
puddling furnace, the fire of which was urged by a blast. The fire was
to be kept up until the metal became less fluid, and "thickened into a
kind of froth, which the workman, by opening the door, must turn and
stir with a bar or other iron instrument, and then close the aperture
again, applying the blast and fire until there was a ferment in the
metal." The patent further describes that "as the workman stirs the
metal," the scoriae will separate, "and the particles of iron will
adhere, which particles the workman must collect or gather into a mass
or lump." This mass or lump was then to be raised to a white heat, and
forged into malleable iron at the forge-hammer.
Such was the stage of advance reached in the manufacture of bar-iron,
when Henry Cort published his patents in 1783 and 1784. In dispensing
with a blast, he had been anticipated by the Craneges, and in the
process of puddling by Onions; but he introduced so many improvements
of an original character, with which he combined the inventions of his
predecessors, as to establish quite a new era in the history of the
iron manufacture, and, in the course of a few years, to raise it to the
highest state of prosperity. As early as 1786, Lord Sheffield
recognised the great national importance of Cort's improvements in the
following words:--"If Mr. Cort's very ingenious and meritorious
improvements in the art of making and working iron, the steam-engine of
Boulton and Watt, and Lord Dundonald's discovery of making coke at half
the present price, should all succeed, it is not asserting too much to
say that the result will be more advantageous to Great Britain than the
possession of the thirteen colonies (of America); for it will give the
complete command of the iron trade to this country, with its vast
advantages to navigation." It is scarcely necessary here to point out
how completely the anticipations of Lord Sheffield have been fulfilled,
sanguine though they might app
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