James Watt

Scottish inventor

• Born: January 19, 1736
• Birthplace: Greenock, Renfrewshire, Scotland
• Died: August 25, 1819
• Place of death: Heathfield Hall, near Birmingham, Warwick, England

Recognized as a great inventor in his own day, Watt developed a practical steam engine and thus promoted power-driven machinery—the heart of industrialization—and the beginnings of the Industrial Revolution.

Early Life

James Watt’s father, the elder James Watt, was a general merchant with a special interest in shipping and navigational instruments. A sickly child, the young Watt was tutored at home by his mother, and when he did go to school, he did not excel. His only educational accomplishment was a strong interest in mathematics, science, and mechanical instruments of all kinds.

At age seventeen, James left home for Glasgow with the intention of taking up the trade of making scientific instruments. Work in Glasgow proved scarce, and the only progress Watt made there was to gain the respect of some of the faculty at the university, where his uncle, George Muirhead, was a professor of Asian languages. After a year, James set out for London, the center of instrument production.

Entry into his chosen profession required seven years of service as an apprentice to a member of the guild. It was only through the payment of a sizable amount of money, twenty guineas provided by his father, that Watt found a master who was willing to violate the guild’s regulations. Another difficulty facing Watt was the prospect of being pressed into the British navy, then involved in the Seven Years’ War. In poor health, impoverished, and living in hiding from the press gangs, Watt nevertheless used his year in London wisely, becoming an expert in constructing the delicate instruments required in navigation.

In July, 1756, Watt completed his year in London and returned to Glasgow, where he intended to set himself up as a maker of mathematical instruments. Again, however, Watt faced a recalcitrant guild that refused to allow him to enter business. His friends at the University of Glasgow came to his rescue. Joseph Black, a professor of chemistry and the discoverer of latent heat, and John Robison, a student and later professor of natural philosophy at Edinburgh, became his lifelong friends. The university was not bound by the rules of the town, and so it was that Watt came under its protection as official mathematical instrument maker of the university.

Watt was twenty-one in the summer of 1757, when he began his job with the university, marking a turning point in his life. He had not only a workshop but also the creative environment of the university. Also, his post required the repair of whatever instruments were brought to him, providing the opportunities to exercise his natural talent for invention. He became proficient at making navigational and musical instruments, and he was soon able to rent a small shop in Glasgow (his relations with the local guild had improved) while maintaining his connection with the university.

On July 16, 1764, at the age of twenty-eight, Watt married Margaret Miller, his cousin and a great source of encouragement to the inventor. He moved out of his university room and purchased a small home nearby. Drawings and paintings of Watt show a tall, handsome man, rather Jeffersonian in appearance, who wore his hair well over his ears, as was the style. Along with his prominent forehead and thoughtful expression, most portraits show a slight stoop to the shoulders and generally suggest a delicate constitution. At the time of his marriage, Watt’s own efforts had not been particularly rewarding; in fact, he was poor. He continued to tinker with the instruments and machines brought to him for repair. One of them was a steam engine.

Life’s Work

James Watt did not invent the steam engine. Such machines, called fire engines, had existed for some time, used primarily to pump water from mines. The most commonly employed type was the Newcomen engine, named for Thomas Newcomen, but these early engines were so enormously clumsy and inefficient that they were hardly used. For some time Watt had discussed the possibilities of steam power with his university associates and had begun experiments with high-pressure steam. Moreover, the university had acquired a defective model of the Newcomen engine and had turned it over to Watt. In the early 1760’s, Watt repaired the university’s steam engine and in the course of doing so became determined to develop a more practical, efficient version. He would make a real steam engine.

The principle of the Newcomen model was that condensed steam in a cylinder produced a vacuum, resulting in pressure that moved a piston, which, when attached to a beam or lever, could be used to work a pump. With an automatic valve gear, the operation could, in theory, be repeated indefinitely. The inefficiency of the Newcomen model stemmed from the fact that at every stroke the water had to be heated to boiling to produce the steam and then cooled to allow condensation. This limitation and the enormous waste of heat meant that in actuality the Newcomen model could make only a few strokes before being heated again.

Little was known about the properties of steam when Watt began his experiments, and, as his notebooks show, his investigations were exhaustive. He was helped immensely by the work of his friend Black, who had discovered latent heat, the heat generated or absorbed as water changes states. Watt correctly surmised that the chief problem of the Newcomen engine was in the loss of latent heat. In May, 1765, Watt reached his fundamental theoretical conclusion about the nature of an efficient steam engine: the concept of a separate condenser so that the boiling water could be condensed into steam without cooling the cylinder. With no injection of cold water into the cylinder, it would remain quite hot, and efficiency would be vastly increased. This was the single most important improvement Watt, or anyone, made on the steam engine.

Watt added other innovations that also increased efficiency. He used an air pump to remove the condensed steam, and he improved the vacuum by tighter packing lubricated with oil. Newcomen’s engine had been open at the top for the piston rod; Watt enclosed it with steam-tight stuffing around the rod. He also insulated the cylinder with a steam jacket. Basically, however, his first steam engine was of three parts: the cylinder and its piston, the separate condenser, and the air pump.

The experiments to produce such a working steam engine were expensive. Watt was a master craftsman who refused to take shortcuts, and the expenditure of his time and materials had left him in debt. He clearly saw that his engine would be a great commercial success, but he also knew that he lacked the financial resources to bring it to the market. His first patent was not obtained until 1769, four years after the discovery of his fundamental principles. In the intervening years he supported himself as a civil engineer, doing surveys for canal construction. He also obtained a partner, John Roebuck, to underwrite the cost of refinements on his steam engine.

Roebuck himself soon faced financial problems, and by 1773 Watt’s personal life took a dramatic turn for the worse with the death of his wife. He was now a widower with two small children and a partner who had gone bankrupt. The following year, however, brought a new partner: the wealthy and renowned Matthew Boulton, owner of the Soho Works in Birmingham. Boulton had admired Watt’s work for some time and had assisted in obtaining the patent, and his purchase of Roebuck’s share of the steam engine brought success to Watt’s efforts. The partnership was a highly lucrative one. Boulton not only was a financial wizard but also was wise enough not to interfere with Watt’s inventive abilities. Over the next ten years, these two men changed the course of history.

Watt continued to modify his engine, and by 1783 it was used widely in mining. His later inventions adapted the steam engine to power other machinery, and the Industrial Revolution, based on Watt’s steam engine, was under way. In 1800, Watt’s patent expired, and he turned his share of the business over to his son James. The inventor then retired, quite wealthy, to Heathfield Hall, a home he had built near Birmingham, where he continued to work on mechanical inventions.

Before moving to Birmingham, Watt had remarried, to Ann MacGregor. They produced two children, both of whom died young. Watt’s old age was serene. He had developed many warm friendships, as well as a gentle personality characterized by modesty, wide-ranging interests, and a sense of humor. He died peacefully on August 25, 1819, at Heathfield, and was buried at the nearby church of Handsworth.

Significance

Without the steam engine, James Watt would be remembered only as an inventor. He made a significant contribution to the understanding of the composition of water and invented a machine to copy sculpture as well as a letter-copying press. His steam engine, however, was an invention of paramount importance. Before Watt, the fire engine was so inefficient as to be hardly used at all. After him, it was the first motor of the Industrial Revolution. Other technological advances were critical to that great process, but it was Watt who created the reality of power-driven machinery—critical to industrialization. For that triumph he received substantial recognition in his own life. He won admission into the Royal Societies of Edinburgh and London, along with an honorary degree from the University of Glasgow. In 1814, he received the high honor of being one of the eight non-Frenchmen accepted into the Academy of Sciences in Paris. The British government offered him noble rank, but he declined. The greatest honor, and the one by which he is known throughout the world, came after his death. In 1882, his name was given to the basic unit of power, the watt.

Bibliography

Arago, Dominique François Jean. Historical Eloge of James Watt. Translated by James P. Muirhead. London: John Murray, 1839. An early biography prepared on the occasion of Watt’s induction into the French Academy of Sciences.

Crowther, James G. Scientists of the Industrial Revolution: Joseph Black, James Watt, Joseph Priestley, Henry Cavendish. Philadelphia: Dufour Editions, 1963. Containing separate treatments of each scientist, this work places Watt in the context of the scientific developments of his time.

Dickinson, H. W., and Rhys Jenkins. James Watt and the Steam Engine. Oxford, England: Clarendon Press, 1927. Reprinted in 1981, this work originated with the 1919 celebration of the century since Watt’s death. Despite its date, the volume is thorough and well worth consulting.

Lord, John. Capital and Steam-Power, 1750-1800. 2d ed. New York: Augustus M. Kelley, 1965. Originally published in 1923, this remains a good introduction into the setting of eighteenth and nineteenth century engineering and economics.

Marsden, Ben. Watt’s Perfect Engine: Steam and the Age of Invention. New York: Columbia University Press, 2002. A readable, technical biography of Watt. In Marsden’s opinion, Watt was less an innovator than a practical businessman with an interest in natural philosophy. Marsden describes how Watt developed the steam condenser to make Newcomen’s engine more efficient.

Miller, David Philip. Discovering Water: James Watt, Henry Cavendish, and the Nineteenth Century “Water Controversy.” Burlington, Vt.: Ashgate, 2004. Describes how Cavendish’s and Watt’s discovery that water was a compound, not an element, became an issue of controversy among nineteenth century scientists.

Robinson, Eric, and Douglas McKie. Partners in Science: Letters of James Watt and Joseph Black. Cambridge, Mass.: Harvard University Press, 1970. Not limited to the correspondence between the two men in the title, this volume of primary material not only reveals the personal side of Watt but also tells much about scientific and technical development in the early days of the Industrial Revolution.

Robinson, Eric, and A. E. Musson. James Watt and the Steam Revolution: A Documentary History. New York: Augustus M. Kelley, 1969. Appearing two hundred years after Watt’s first patent, this excellent book illustrates Watt’s inventive genius.

Uglow, Jenny. The Lunar Men: Five Friends Whose Curiosity Changed the World. New York: Farrar, Straus, Giroux, 2002. Watt, his partner Matthew Boulton, and scientist Joseph Priestley were among the founders of the Lunar Society of Birmingham. Uglow’s book describes how the organization invented new products, advanced science, and worked on other projects that ushered in the Industrial Revolution.

Webb, Robert N. James Watt: Inventor of a Steam Engine. New York: Franklin Watts, 1970. Webb’s work is useful as an introduction to Watt.