Matthew Boulton

Matthew Boulton (1728-1809), English manufacturer and engineer, who as the partner of Scottish instrument maker James Watt helped build and promote an efficient steam engine. Boulton was born in Birmingham. He took over his father’s silver stamping business and in 1762 built a new metalworking factory in Soho. The rapid growth of the factory led to a need for more power than could be generated by traditional water-driven machines, so Boulton began to take an interest in the technological advances of steam engines.

In the early 1700s English inventor and blacksmith Thomas Newcomen had developed a crude but usable piston engine. The Newcomen engine had several drawbacks: It consumed 13 tons of coal a day; it was capable of only 12 strokes a minute; it did not conserve the steam well; and it only exerted force while the piston was moving in one direction.

Watt, an engineer and instrument maker for the University of Glasgow, developed an improved engine in 1763. Among his many innovations, Watt patented a separate condenser that made it possible to keep the cylinder hot, an air pump to draw off the vapors from the cylinder after each stroke, and a cylinder head to force the piston down by steam instead of atmospheric pressure.

Seeing the enormous potential value of Watt’s innovations, Boulton entered into a business partnership with him in 1769. By 1775 the two men had obtained a 25-year extension of the engine’s patent and were partners in a steam engine business. They improved the engine until the fuel costs for their engines were 75 percent less than those for similar Newcomen engines, and they sold the steam engines on the basis that one-third of the fuel savings be paid to them.

The combination of Boulton’s business skills and Watt’s inventiveness insured that the steam engine would become the most important source of power during the Industrial Revolution. Boulton and Watt eventually became rich and famous through the sale of their steam engines. They also used steam power to improve coining machinery, and they supplied coins to Britain, the English East India Company, and several foreign governments.