The English inventor and engineer Thomas Newcomen (1663-1729) developed the first practical steam engine, an important feature of the industrial revolution.

Thomas Newcomen was born on Feb. 24, 1663, at Dartmouth, Devonshire. It seems probable that as a youth he was apprenticed to learn the blacksmith trade and later became an itinerant ironmonger, a craftsman who made tools, nails, and other hardware, which he sold throughout the mining areas about Dartmouth.

Many mines at that time had been dug so deep that they were constantly flooded, and to continue them in operation the operators had to find a better means to pump out the water. It was this omnipresent problem which led Newcomen to attempt to devise a machine which could drive a water pump. As to how Newcomen might have achieved this, 18th- and 19th-century writers usually pointed to earlier attempts to use steam as a motive force. However, no evidence has been found of any borrowing on the part of Newcomen. On the other hand, he never took out a patent of monopoly on his engine, as Thomas Savery did in 1698, because Savery's patent covered all means utilized to raise water by fire. This is probably why Newcomen found it necessary to purchase, from the proprietors of the Savery patent, the right to build a steam engine--a transaction which probably occurred about 1705. Thus it is doubtful whether Newcomen benefited financially from his invention, since it had to be exploited under another's patent. The first Newcomen engine which can be documented dates from 1712. It has been estimated that it required at least 10 to 15 years of development. Both the Newcomen and Savery engines were based upon the use of condensed steam; however, they also differed in important fundamentals.

The basic principle of Newcomen's engine was simple. Steam was injected into a cylinder, forcing a piston to move out. Cold water was then sprayed into the piston, the steam condensed, and a partial vacuum was formed. Atmospheric pressure then returned the piston to its original position, so that the process could be repeated. The piston's reciprocating motion was finally transferred to a water pump by a beam which rocked about its center. That this to-and-fro motion might somehow be transformed into the more useful rotary motion was a problem which had not as yet been recognized.

Newcomen's steam engine spread throughout the mining area of England and rescued many mines from bankruptcy. It was not until John Smeaton's and, more important, James Watt's versions of the steam engine were developed, almost three-quarters of a century later, that Newcomen's machine was superseded. Newcomen died in London on Aug. 5, 1729.

Further Reading

• A biography of Newcomen is L. T. C. Rolt, Thomas Newcomen (1963). Some material on him is in H. W. Dickinson, A Short History of the Steam Engine (1939).