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James Watt lived from 19 January 1736 to 19 August 1819. He was an engineer and inventor whose improvements to the steam engine were fundamental in bringing about the industrial revolution. He was once described as the 22nd most influential man in history: and the SI unit of power, the Watt, is named after him. The wider picture in Scotland at the time is set out in our Historical Timeline.
James Watt was born in Greenock on the River Clyde. His father was a wealthy shipbuilder and shipowner and his mother also came from a privileged background. James was not a healthy child and most of his schooling was undertaken at home by his mother.
Watt's mother died when he was 17 and his father's business no longer thrived as it had. James spent a year in London studying the manufacture of mathematical instruments before returning to Scotland to set up business in Glasgow. Because he had not spent seven years as an apprentice, the Glasgow Guild of Hammermen, whose authority covered any craftsman using a hammer, obstructed his plans. A Professor at Glasgow University, Joseph Black, arranged instead for Watt to set up his workshop within the university, which he did in 1757.
Watt began experiments with steam in the early 1760s. Glasgow University had a model of a Newcomen engine that had failed to work. Watt worked on the model engine in 1763, and managed to make it function, but very poorly. During this process, Watt discovered that the problem lay in the fact that the steam was condensed within the same cylinder in which it was also expected to expand to move the piston during another part of the power cycle. Watt calculated that 80% of the energy in the steam was wasted on heating up the cylinder every cycle. His key innovation was to have the steam condense in a separate vessel, allowing the actual cylinder to remain hot throughout the process.
A working model had been completed by 1765 and this proved the concept, showing dramatic improvements in efficiency over the basic Newcomen engine. It took another decade for the first full scale engines to be produced, first working in secret at Kinneil House near Bo'ness, but finally as a result of his partnership with Matthew Boulton whose Soho foundry in Birmingham had the facilities and skills needed to manufacture the engines.
Over the following decades Boulton and Watt made a series of important improvements to their steam engines, and by the mid 1780s their engines were five times as efficient as the Newcomen engine they were rapidly supplanting, as what we now know as the industrial revolution gathered pace. Amongst those to work with and be influenced by James Watt during this period was John Rennie, who went on to be a notable civil engineer.
Watt retired from steam engine manufacture in 1800, but continued to work on inventions in a number of areas. He died a wealthy man in 1819. The Boulton and Watt company continued to thrive in the hands of its founders' sons who took as a partner William Murdoch. Murdoch had been an employee of the company for many years and had been instrumental in bringing about many of the improvements in their steam engine design.
Watt's historical importance is commented on in the opening paragraph above. In addition he was made a fellow of the Royal Society of Edinburgh and of the Royal Society of London; and he was made one of a small number of foreign associates of the French Academy of Sciences. There are statues of him at Westminster Abbey; in Brimingham; and at his birthplace in Greenock. He is also remembered in the name of one of Edinburgh's Universities, Heriot-Watt University, and in the James Watt College in his native Greenock. And there is a museum in Birmingham devoted to the lives of Boulton and Watt.