James Watt

James Watt was a Scottish engineer, chemist and inventor, whose innovations had a major impact upon the industrial revolution.

Watt did not invent the steam engine, but he made a significant improvement to its efficiency. Soon steam came to power almost every facet of the revolution in industrial production – from iron, textiles and mining to steamboats and locomotives.

Born in 1736 to a prosperous Greenock shipbuilder, Watt was fascinated by chemistry from an early age. At the age of 17, his life took a dramatic turn when his mother died, his father’s firm failed and he had to leave home to make his way in the world.

After a year in London, he was employed to repair scientific instruments at the University of Glasgow, where he became friends with chemist Joseph Black and economist Adam Smith. It was during this period that Watt had the idea that would make his name.

Before Watt, steam engines were mostly based on Thomas Newcomen’s 1712 design, which relied upon the repeated heating and cooling of a steam cylinder. Watt observed that this wasted a significant amount of energy. His solution was a separate condenser. This would remain cold, allowing the cylinder to remain hot, thereby avoiding wastage caused by unnecessary heat loss and making the whole process many times more efficient.

His innovation was patented in 1769, but construction of the prototype proved difficult, and it was not until Watt moved to Birmingham to partner with industrialist Matthew Boulton that his steam engine was able to reach its full range of industrial applications.

Watt combined theoretical scientific knowledge and insights with practical – and highly commercial – applications. He retired in 1800 a very wealthy man and together with Boulton handed the business over to their sons. Watt continued to invent things after his retirement.

As well as the steam engine, during his lifetime he also developed the concept of horsepower, and the standard unit of power, the watt, is named after him. Widowed twice, Watt was buried on his death at the age of 83 alongside his business partner, Matthew Boulton.