ABSTRACT
In 1712, Thomas Newcomen invented the steam engine. James Watt took out a patent in 1769 for a separate condenser, which greatly improved the performance of the steam engine. The development of the steam engine opened the way to the industrial revolution. The engine used steam, which is raised in a boiler, to produce work for pumping water. This invention pointed the way to converting heat into work. One of the fi rst questions that arose with the invention of the heat engine was how much work could an engine produce per unit heat input. Another question was could it be improved, and by how much.
