Henry Cort

The English ironmaster Henry Cort (1740-1800) made possible the large-scale and inexpensive conversion of cast iron into wrought iron, one of the most essential materials of the early industrial revolution.

Henry Cort was born in Lancaster. His father was a mason and brickmaster. Young Cort became a supplier of naval provisions and by the 1770s had accumulated a small fortune.

In 1775, after years of experimenting with improved methods for wrought-iron production, Cort purchased a forge and slitting mill at Fontley. He tried to find an easy way to convert cast iron into wrought iron; traditionally a smith had hammered the iron in a forge. He patented grooved rollers in 1783 which replaced most of the hammering. By 1784 Cort worked out a process of pudding, whereby molten pig iron was stirred in a reverberatory furnace. As the iron was decarbonized by air, it became thicker, and balls of "puddled" iron could be removed as a pasty mass from the more liquid impurities still in the furnace. Puddled iron, like wrought iron, was tougher and more malleable than pig iron and could be hammered and finished with the grooved rollers. He also devised a process whereby red-hot iron was drawn out of the furnace through grooved rollers which shaped the puddled iron into bars, whose dimensions were determined by the shape of the grooves on the rollers. The rollers also helped squeeze out impurities, and preliminary shaping into bars made the iron more readily utilizable for the final product.

There were many advantages to these processes. Puddling used the plentiful coke, instead of the expensive charcoal. The combination of puddling and grooved rollers was a process that could be mechanized, for example, by the steam engine, which had just been introduced. The result was that production of wrought iron was increasingly carried out in a group of coordinated processes in a single economic unit, with reverberation processes in a single economic unit, with reverberation and blast furnaces operating side by side. This increased production at a greatly reduced cost, and for the first time iron became one of England's exports.

To obtain more capital, Cort took a partner, Samuel Jellicoe, who put up large sums of money. Jellicoe's father had embezzled these funds from the British government, and when this was discovered, Cort was completely ruined and lost his patent rights. As an acknowledgment of the value of Cort's patents, however, the government granted him a small pension in 1794. Cort died a poor man; he was buried in Hampstead, England.

Further Reading

There is no biography of Cort. Material on him can be found in T.S. Ashton, Iron and Steel in the Industrial Revolution (1924; 2d ed 1951) and The Industrial Revolution: 1760-1830 (1948; rev. ed. 1964). John C. Hammond and Barbara Hammond, The Rise of Modern Industry (1925; 9th ed. 1966), is a classic study that includes information on Cort.

Additional Sources

Mott, R. A. (Reginald Arthur), Henry Cort, the great finer: creator of puddled iron, London: Metals Society, 1983. □

Henry Cort

1740-1800

English Inventor

Henry Cort developed two iron-making processes that, when combined, led to a fourfold increase in iron production throughout Britain within two decades. His patented grooved rollers and a puddling process for separating iron from carbon should have made him rich, but due to a disastrous business partnership, Cort was denied the fruits of his labors.

Cort was born in Lancaster, England, in 1740, and by the age of 25 was serving in the Royal Navy. In that capacity, he was responsible for improving ordnance made from wrought iron—primarily cannon balls. He soon became fascinated with the subject of ironworking, and using funds he had managed to accumulate, started his own iron business.

Cort's first major breakthrough was a process for creating iron bars with the use of grooved rollers, which replaced an older method of manually hammering the bars into shape. He patented the process in 1783. A year later he patented a second process, this one for separating out carbon by stirring molten pig iron in a reverberating furnace. As the iron decarburized, this had a purifying effect.

The two processes proved most useful when applied in tandem, and ironworking flourished throughout Britain as a result of Cort's two breakthroughs. Unfortunately, he was not able to enjoy his success. He had entered into a partnership with Samuel Jellicoe, whose father was a corrupt naval official involved in embezzlement of public funds. Because some of those funds wound up in the Cort-Jellicoe partnership, the British government punished Cort—though he had taken no part in the crime—by seizing the rights to his patents.

As a result of this misfortune, Cort's competitors were able to benefit from his efforts. Cort himself lived out his days on a small pension, and died at the age of 60 in Hampstead, London.

JUDSON KNIGHT

Cort, Henry (1740–1800). Cort was born at Lancaster, son of a mason. He became an agent to the navy in the 1760s and his interest in the production of iron developed after the Russians had raised their prices. By 1784 he was able to patent an invention for ‘puddling’ iron to make it malleable. With Adam Jellicoe he entered into large naval contracts, but Jellicoe's death in 1789 revealed fraud, which brought Cort down. During the last years of his life, he existed on a small pension. During his lifetime, the production of iron in Britain rose from some 30,000 tons to well over 200,000 tons.

J. A. Cannon