By Tim Lambert
James Watt was a great Scottish engineer of the 18th century. He did not actually invent the steam engine. Instead, he greatly improved it. A man named Thomas Savery invented the first primitive steam engine in 1698. A man named Newcomen started making steam engines to pump water from mines in 1712. However, Watt is famous for inventing an improved version in 1769.
James Watt was born in Greenock on 19 January 1736. His father, also called James was a shipbuilder. As a boy, Watt went to the local grammar school where he learned the classics and mathematics. However, Watt also liked making models.
Eventually, James decided to become a maker of mathematical instruments such as quadrants and compasses. In 1755 he went to London. However, he did not stay there long. In 1757 Watt moved to Glasgow. In 1764 Watt mended a model of a Newcomen steam engine. In a Newcomen, engine steam is admitted into a cylinder then condensed back into the water.
In 1765 Watt realized it would be more efficient to condense the steam in another chamber separate from the cylinder. However, it was not until 1769 that Watt patented his new idea, the separate condenser.
Meanwhile, in 1764 James Watt married a woman named Margaret Miller. The couple had 6 children but Margaret died after 9 years.
In 1766 Watt got a job as a land surveyor marking out the land for canals. Then in 1774, James Watt moved to Birmingham. In 1775 he went into partnership with Matthew Boulton and began making steam engines. His steam engines were used for pumping water out of mines and gradually he became a wealthy man.
Then in 1776, James Watt married Ann MacGregor. They had 2 children.
By 1780 the Industrial Revolution was beginning to transform life in Britain and Watt adapted his steam engine to provide a rotary motion so they could be used to power machines in the new factories. In 1781 he made the sun and planet gear to do this. In 1785 steam engines were used to power machines in cotton mills for the first time. Meanwhile in 1782 Watt invented another major improvement the double-acting steam engine. In 1788 Watt invented the fly ball governor to regulate the speed of steam engines and in 1790 he invented a pressure gauge.
In 1785 James Watt was elected a fellow of the Royal Society.
James Watt retired from business in 1800. Watt died on 25 August 1819 and he was buried in Birmingham. Finally, in 1882, a unit of electrical power was named the watt in his honor.