How much do you know about the famous inventor? Here, we look back at his life…
Born: 18 January 1736, in Greenock
Died: 25 August 1819, in Handsworth, Birmingham
Family: His father, also James Watt, was a prosperous shipbuilder, and his mother, Agnes Muirhead, came from a distinguished family and was well educated.
Watt was twice married: to Margaret Miller from 1764 to 1773 and Ann MacGregor from 1776 to 1819. Margaret died in childbirth in 1773, leaving Watt with two young children. He married Ann in 1776 and had a son and a daughter. Both died of consumption before their father’s death.
Remembered for: His improvements to the Newcomen steam engine, and as a key player in the Industrial Revolution. The watt – a unit of measurement of electrical and mechanical power – is named after him.
His life: Despite being born into a reasonably wealthy family, Watt’s teenage years were difficult – his father’s health started to fail, as did his business, and in 1753, when Watt was aged 17, his mother died. So from 1755 Watt worked in London as a maker of mathematical instruments.
Watt later returned to Scotland, and was hired privately by Glasgow University to repair their academic instruments. There, in the shop in which he worked, the scholar John Robinson introduced Watt to the science of steam.
In around 1763, Watt was given a model Newcomen engine to repair. Upon realising it was inefficient, Watt set to work on improving the design: he ultimately devised a separate condensing chamber for the steam engine that prevented enormous losses of steam.
Watt’s first patent covering this device was secured five years later, in 1769. He spent the next year working on and testing a model, but it continued to fail. Watt then entered what would prove to be the lowest point in his life: his partner and backer – the inventor John Roebuck – went bust, and in 1772 Watt’s wife, Margaret, died in childbirth.
But Watt’s luck turned when in May 1774 he met Birmingham-based businessman Matthew Boulton, who took over Roebuck’s interest. Creditors believed the patent worthless, but together, under the name Boulton & Watt, the pair established the most important engineering firm in the country.
Matthew Boulton. (Photo by The Print Collector/Print Collector/Getty Images)
The duo manufactured steam engines to huge demand from mine owners, distilleries, waterworks and paper, flour, cotton and iron mills, reportedly making money by charging a third of the cost of the coal that would have been used in the Newcomen model. The pair also worked on the engine used in the first commercial steam-powered ship in America in 1807.
By 1786 Boulton & Watt were “worldwide celebrities”, and by 1790 the pair had acquired considerable wealth. The pair set up one of the first benefit societies for their workmen, and became leading figures in the industrial revolution
Boulton and Watt steam engine workshops, Soho, near Birmingham, 18th century. (Photo by Liszt Collection/Heritage Images/Getty Images)
Watt became a fellow of the Royal Society of Edinburgh and the Royal Society of London, and a foreign associate of the French Academy of Sciences.
In 1800, after working together for a quarter of a century, both Watt and Boulton retired, handing over their business to their sons. Watt spent his retirement years focusing on his research, and he patented a number of other inventions including the steam indicator, which records the steam pressure inside the engine, and the rotary engine.
Watt died on 25 August 1819, aged 83, and was buried in Birmingham alongside his business partner, Matthew Boulton.