James Watt: Industrial Revolution Spark Plug and Enlightenment “New Philosopher”

Was James Watt (1736–1819), born in Greenock, Scotland, a mechanical engineer, businessman, chemist, and inventor, also a “new philosopher”—the name that Enlightenment intellectuals adopted? 

One of the most prominent chemists of the time, Humphry Davy (1778–1829), said of Watt: “Those who consider James Watt only a great practical mechanic form a very erroneous idea of his character; he was equally distinguished as a natural philosopher and a chemist, and his inventions demonstrate his profound knowledge of those sciences, and that peculiar characteristic genius, the union of them for practical application.”

With his own bench and tools in his father’s shop for shipbuilding (Greenock developed into a major seaport connecting Scotland to the Americas via the River Clyde), Watt had made models and become familiar with instruments used on ships. It made him a practical inventor and determined him by age eighteen to become a mathematical-instrument maker, a trade he learned as an apprentice in London until poor health sent him back to Glasgow. 

Watt, then, exemplifies two closely related themes of the Age of Enlightenment. First was the conviction that all knowledge in every field was for the ultimate purpose of improving human life. Second was the moral imperative to pursue such applications of knowledge. Almost certainly, that imperative motivated Adam Smith (a friend, mentor, and supporter of the young James Watt) to redirect his efforts from philosophy (The Theory of Moral Sentiments) to economics (The Wealth of Nations). Watt was a famous member of the Lunar Society of Birmingham, a virtual roster of British Enlightenment figures (and correspondents from abroad such as the Irish novelist Maria Edgeworth).

Another indication of Watt’s broader Enlightenment view: born into a Presbyterian family, he later in life became a deist. 

The world of the Scottish Enlightenment seems small, chiefly in Edinburgh and Glasgow, both with major universities, though the “new philosophers” often discussed their ideas in pubs and clubs. (That is where the young poet Robert Burns joined the Enlightenment pack.) And so, Joseph Black and Adam Smith were employers of Watt (at the University of Glasgow) and later of his friends and investors. 

Black and Smith, among others, hired the young Watt as a mathematical-instrument maker at the University of Glasgow. There, Watt became interested in steam engines. He did not invent the steam engine; Thomas Newcomen’s “Newcomen engine” was used for half a century before Watt came on the scene to power pumps used in mines.

There were no theoretical underpinnings for Watt’s work. The science of thermodynamics was a century in the future. Here, as so often, an invention was based on principles not discovered until much later. 

The insight of Watt, while repairing a Newcomen engine at the university, was that it wasted more energy than it delivered to the pumping job. The problem is a bit difficult to grasp, but the Newcomen engine kept cooling and reheating the steam cylinder to control pressure. This “housekeeping” took a lot of energy. Watt enhanced the steam engine by putting that function in a separate condenser (his most famous single innovation). He got his patent in 1789, with some financial support from Joseph Black; and, later, Watt’s steam engine became five times as efficient as the Newcomen engine (and kept improving with new inventions by Watt). 

But financial stringencies at this time forced him to work for eight years as a surveyor planning the routes of Scottish canals. And then, for years, Watt worked at installing his engines in mines, chiefly in Cornwall, England. Nothing worked very well financially until Watt, who loathed negotiations and all financial dealings, formed a partnership with Matthew Boulton (1775) that lasted most of Watt’s working life and made him a rich man. Without Matthew Boulton’s entrepreneurship and capital, would we have heard of James Watt today?

The big breakthrough came when, urged by Boulton, Watt figured out how to apply steam power not only to reciprocating motion (the up and down of the pump) but also to the rotary motion of wheels, replacing both the horse and the waterwheel as the chief source of power to drive the machinery of factories during the Industrial Revolution. He patented, too, the double-acting engine and an early steam locomotive. 

In the process, Watt developed the concept of “horsepower” and, of course, lends his name to the “watt.”

None of it came easily. The struggles of Watt recall Thomas Edison’s relentless experiments in New Jersey to find a workable filament for the electric light bulb. Among the most famous of Watt’s quotes, and there are a few, is “I can think of nothing else than this machine.” Watt’s design for his more efficient steam engine required precision machining (boring) of cylinders, but most such work was done by blacksmiths. Only when Watt met James Wilkinson, the legendary steel master of Britain, did he get the machinists he needed to bore a smooth cylinder.

Watt was in and out of bankruptcy, with never enough capital to fully commercialize his inventions. When he got the steam-engine business going, at last, on a profitable level, his patents were pirated by businessmen who thought he could not defend them. Watt did defend them in court, winning every case, but he never recovered all the profits that had been pirated.

He nevertheless retired a wealthy man. With his wives from two marriages, he had many children who survived childhood (a major concern, then), and to them he left his patents and his interest in his business, as his associate, Boulton, left his interest to his heirs.

Retired from business, Watt continued his experiments and inventions. One was a machine for copying documents that he perfected and that was used into the early twentieth century. He became a Freemason, a fascinating sidelight on so many Enlightenment “new philosophers,” from Francis Bacon to Voltaire to Benjamin Franklin.

Watt died at age eighty-three and is buried beside St. Mary’s Church, in Handsworth, Birmingham. He had been honored often, including by election in 1785 to the Royal Society of London. Statues of Watt can be viewed in London, Birmingham, and Liverpool. It was steam power, especially applied to rotary motion, that drove the Industrial Revolution (1760–1840). 

Ralph Waldo Emerson lifted Watt into the pantheon of history’s creative geniuses, but, more sublely—and more importantly—dispensed with the distinction between the so-called artistic genius and military glory and the mere realm of industry and making a living:

“Raphael paints wisdom, Handel sings it, Phidias carves it, Shakespeare writes it, Wren builds it, Columbus sails it, Luther preaches it, Washington arms it, Watt mechanizes it.”