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FORE:[See larger version]The employment of pit-coal had not reached perfection, and in 1785 the Society of Arts offered a premium for the making of fine bar iron with pit-coal. This object was accomplished by Mr. Cort, an iron-founder of Gloucestershire, by exposing the pig iron on the hearth of a reverberatory furnace to the flame of pit-coal. This process was improved into what was called puddling, in puddling or reverberatory furnaces. Cort also introduced the drawing out of iron between cylindrical rollers; but he became ruined in his experiments, and other iron-masters of more capital came in to reap the profit. Many years passed before a pension was conferred on some of his children for his services. In 1755 the whole population of Carron was only one thousand eight hundred and sixty-four; in 1795 the workmen alone employed in the works were one thousand, the population four thousand, when the foundry had five blast furnaces, sixteen air furnaces, three cupola furnaces, and consumed one hundred and thirty-six tons of coals daily. It supplied to the Government eleven thousand tons annually of cannon, mortars, shot, shells, etc.; to the East India Company six thousand tons; and to all customers together twenty-six thousand tons. The growth of the iron trade in Great Britain, through these improvements, may be seen from the fact that in 1802 there were one hundred and sixty-eight blast furnaces, producing two hundred and twenty thousand tons of iron; in 1820 the annual production of iron was four hundred thousand tons; in 1845 the production was calculated at twice that amount��that is, in twenty-five years the production had doubled itself. In 1771 the use of wire ropes, instead of hempen ones, was suggested by M. Bougainville, and this was made a fact by Captain Brown, in 1811. Before this, in 1800, Mr. Mushet, of Glasgow, discovered the art of converting malleable iron, or iron ore, into cast steel; and in 1804 Samuel Lucas, of Sheffield, further extended the benefit by the discovery of a mode[198] of converting any castings from pig iron at once into malleable iron, or cast steel, so that knives, forks, snuffers, scythes, and all kinds of articles, were converted into steel, "without any alterative process whatever between the blast furnace and the melting-pot." In 1815 it was calculated that two hundred thousand persons were employed in manufacturing articles of iron, the annual value of which was ten million pounds.

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