Scotsman James Watt is best known for the invention of the steam machine - his invention was the engineering power that made the industrial revolution possible and forever changed the world as we know it. But he didn't actually invent the steam engine as many believe - he was, in fact, inspired by an existing steam engine.
The Newcomen Steam Engine
As a respected mechanical engineer, James Watt had connections at the University of Glasgow. They needed their Newcomen steam engine repaired and asked James Watt to fix it for them. While working on this engine, he realised that the current designs wasted too much energy. Watt enhanced the design by adding a seperate condenser that would prevent a waste of energy, which made the machine much more powerful and efficient.
James Watt was the person who developed the “horsepower” concept and to honor his inventions, the SI unit for power, Watt, was named after him.
James Watt's other main invention was that of the copy machine. At the time, in the 1780s, there was no way to effectively make precise copies of drawings or letters without doing it by hand, or by using linked pens on multiple pieces of paper. James Watt created a way to make photocopies, by transfering ink from the original's front part to the back of another paper sheet (by which it was duplicated exactly) and he also developed a press to effectively do the transfer. His invention was a milestone in the evolution of the copy machine.
James Watt invented a couple of working machines to copy medallions and sculptures, but he never patented it. He also enjoyed experimenting with chemistry and figured out how to combine certain chemicals to create a very effective, cheaper type of bleach.