• In 1764, Watt received a Newcomen steam engine to repair.
• The 1712 Newcomen engine worked by condensing steam in a cylinder, which then creates enough push to power a piston.
• While fixing the engine, James Watt noticed that more than three-quarters of the steam was wasted due to repeated heating and cooling in the same cylinder.
• He then designed a cylinder that had a separate chamber to condense the steam in. Watt's engine kept the cylinder at a stable temperature as the steam condensed in a separate chamber. This was revolutionary.

• James Watt lacked capital and was initially unable to construct a full-scale engine.
• In 1766, with investment from Joseph Black, Watt created a successful small test engine.
• A year later, Watt started a business partnership with John Roebuck, and they took out their famous patent for "A New Invented Method of Lessening the Consumption of Steam and Fuel in Fire Engines."
• Acquiring the patent used all of Watt's money, and he was forced to take on alternate employment.
• Seven years later, Watt's old business partner went bankrupt, and Matthew Boulton, an English manufacturer, acquired Roebuck's patent rights.
• Watt now returned to working full-time on his engine.

James Watt and Matthew Boulton founded a manufacturing firm, where Watt spent years improving the efficiency and cost of his engine.

The demand for Watt's engine grew and was adopted across multiple industries. His steam engine became a "mechanical workhorse of the Industrial Revolution."