On this day 280 years ago the Scottish engineer James Watt was born at Greenock, Scotland. Although he first worked as a maker of mathematical instruments, Watt was fascinated by the steam engine – a simple pumping machine, first developed by Thomas Savery (1698) and further improved by Thomas Newcomen in 1712. When once repairing a Newcomen steam engine, Watt realised that much of the heat-generated energy was wasted, so he put his mind to remedying this defect. He created a separate condenser that maximised energy efficiency and reduced the cost of steam power by 75% – the steam engine became employable on a large scale. However, it required a keen businessman to convert Watt’s invention into a marketable product. In 1774, Matthew Boulton, a Birmingham manufacturer, made Watt join him at his Soho Works, and by November that year JamesWatt had the first machine completed. From 1775 to 1800 Boulton and Watt worked together as partners – Watt constantly worked on further improvements of the engine, patenting various parts, while Boulton gave his support and dealt with everything else. Demands for Watt’s engine grew steadily from all kinds of mills and waterworks. When Watt retired in 1800, he was a wealthy and well-known man. He continued research until his death on 19 August 1819. To honour his contribution to science and industry, a unit of measurement of electrical and mechanical power – “the watt” – was named after him.

James Watt made a number of other inventions, an important one of which was the copying press – built because he needed to ease his burden of business correspondence – which remained in use in large offices for over a century.

(Consulted: Chambers’s Encyclopaedia (1968). Vol. 14, p. 446)

You may also want to take a look at BBC History and the Encyclopaedia Britannica.