THE invention considered by many to have marked the start of the industrial revolution was officially recognised in London 250 years ago today. Describing himself as a merchant from Glasgow, James Watt was granted a patent for his new steam engine on April 29, 1769 – after which the world was changed.

Patent number 913 is arguably one of the most important documents in Scottish history, yet few people in Scotland know anything about it. Its effects can be seen all around us because Watt’s steam engine change the face of Scotland.

DID WATT INVENT THE STEAM ENGINE, THEN?

IT is important to note that James Watt did not invent the steam engine, but with his 1769 patent he vastly improved the original 1712 engine of Thomas Newcomen, so Watt is rightly credited with being the father of steam power.

It was steam-powered energy above all that drove the industrial revolution, although Newcomen engines, known as “common engines” were in widespread use until the 1800s.

WHAT WAS THE PATENT FOR?

PATENT 913 was in its final draft form by April 25, 1769. The original can still be seen today, indeed there are copies available to view online.

Watt had realised many years before that Newcomen’s engines, which were mainly used for pumping water out of mines, were far too inefficient. Furthermore, they were not portable and used large quantities of coal as fuel.

Watt’s genius was to work out a way of greatly improving engine power and reducing the fuel needed for the steam engine which lost much of its power output because it needed constant cooling and heating, its thermal energy failing to efficiently convert into mechanical energy.

After years of experimentation, Watt devised a system of a chamber, separate from the main piston, in which the steam was condensed. Here’s the actual words from the patent: “In engines that are to worked wholly or partially by condensation of steam, the steam is to be condensed in vessells [sic] distinct from the steam vessells or cylinders, although occasionally communicating with them.

“These vessels I call condensers, and whilst the engines are working, these condensers ought at least to be kept as cold as the air in the neighbourhood of the engines by application of water or other cold bodies.”

It seems simple now, but back then such creativity was rare as very few people understood the concepts of energy and thermodynamics.

WHAT WERE ITS EFFECTS?

THE patent did not have an immediate transformative effect. Watt was hampered by a lack of funds, especially after his main supporter, John Roebuck of the Carron Ironworks near Falkirk, went bust.

Watt had to go south for backing and met Matthew Boulton, who had acquired Roebuck’s percentage of the Watt patent. It was to be a fruitful meeting. Boulton ran the Soho Manufactory near Birmingham, and his experienced workers provided Watt with the precise metalworking needed for his new engines.

Watt constantly made new improvements to his engine and soon he and Boulton were making fortunes as their steam engines transformed textile mills and just ab out every other facet of the industrial revolution.

WAS JAMES WATT REALLY A GENIUS?

BACK In The Day in The National tomorrow will feature Hamish MacPherson’s plea for a much greater celebration of Watt on the occasion of the bicentenary of his death on August 25 this year.

Meanwhile here’s what Francis, Lord Jeffrey, wrote in his “Character of Mr Watt” after Watt’s death: “Perhaps no individual in his age possessed so much and such varied and exact information – had read so much, or remembered what he had read so accurately and well.

“He had infinite quickness of apprehension, a prodigious memory, and a certain rectifying and methodising power of understanding which extracted something precious out of all that was presented to it.”

Yes, Watt was a genius and tomorrow you can find out more.