James Watt

1736–1819

JAMES WATT AND THE TEAKETTLE.

The idea of using steam to drive a piston in order to do mechanical work was attempted many years before James Watt was even born. The "Newcomen" engine was first built in 1712, and was used for tasks such as pumping water out of mines. They were large and inefficient, however, and expensive to build and operate. In 1754 James Watt, who worked in a machine shop at Glasgow University, made an important improvement to a Newcomen engine, by adding dual chambers, one where the "work" of the engine was done by the steam, and the other where the steam was cooled to prevent the engine from over-heating.

James Watt's novel idea is usually illustrated by a tea-kettle. A kettle with no lid may take a long time to heat, but it will never explode. A kettle with a tightly closed lid will heat up very efficiently, but will ultimately explode. A tea-kettle on the other hand, is covered, but allows enough steam to escape to avoid catastrophe. In Watt's engine, the chamber where the work was done, was separated from the chamber where the steam was cooled by a similar mechanism. Watt's engine, therefore, was both efficient and safe.

Although Watt's his original idea was sound, and he was able to obtain a patent for it, many years elapsed before it could be successfully manufactured, and during this time Watt developed partnerships with several other engineers, iron workers, and businessmen, and had to solve a variety of difficult problems. Watt's most important long-term partner was Boulton, who had the business sense that Watt lacked. In addition to helping manufacture the first mass producible Watt Steam Engines in 1776 (eight years after Watt completed his prototype), Boulton assisted with several other innovations. In 1781 they patented a steam driven rotational motor which was more portable than their piston driven reciprocal (up-down) engine, and later they developed a governor that helped control the speed at which their engines ran. Both of these inventions made their engine much more practical for manufacturing tasks.

Boulton and Watt were granted numerous patents for these inventions but instead of licensing them, they incorporated and began to mass produce steam engines, and the industrial revolution swung into high gear.

Key events during the life of James Watt:

Year	Event
1736	James Watt born in Scotland to a shipwright.
1758	Set up an instrument shop at Glasgow University.
1762	Began studying steam engines.
1763	Repaired a "Newcomen" engine owned by the University.
1764	Married Margaret Miller.
1765	Produced first working model of the 'Watt' engine (with separate chambers for piston and steam).
1776	Difficult manufacturing problems were finally solved. First commercial engines produced.
1781	Rotational motor driven by steam power introduced.
1794	Boulton and Watt incorporated to mass produce steam engines.
1800	Retired and passed business on to sons.
1819	Death of Watt.

Other Resources

Story Links	Book Links
James Watt and the Invention of the Steam Engine  in	Great Inventors and Their Inventions  by  Frank P. Bachman
James Watt and the Teakettle  in	Thirty More Famous Stories Retold  by  James Baldwin
Story of the Steam-Engine  in	The Struggle for Sea Power  by  M. B. Synge

Image Links
James Watt  in Great Inventors and Their Inventions	Watt and the Teakettle  in Great Inventors and Their Inventions	Watt's Workroom at Hearthfield  in Great Inventors and Their Inventions
Watt and the Teakettle  in Thirty More Famous Stories Retold

Contemporary	Short Biography
Joseph Black	Glasgow Chemist who befriended Watt and help him with his engine.
John Roebuck	First financial backer of Watt's engine. Went bankrupt.
Matthew Boulton	Long term business partner of James Watt.