Who invented the steam engine?

Answer 1

The first person to harness the power of steam was the Greek scientist Heron of Alexandria in the first century A.D. He developed several devices that were operated by water, steam, or compressed air, including a fountain, a fire engine, and the steam engine.

The "steam engines" in use in the 18th century were not strictly steam engines - the weight of a large rocking beam or pump rod pulled a close-fitting piston along a cylinder, drawing in steam from a boiler. The operator closed a valve to shut off the steam, and opened a valve or tap to let cold water into the cylinder, condensing the steam and creating a partial vacuum. The pressure of the outside air then pushed the piston back into the cylinder. This type of engine is known as an atmospheric or condensing engine - the steam played no direct part in transmitting power to the beam or pump rod.

This type of engine was significantly improved in 1712 by Englishman Thomas Newcomen (1663-1729), who built a machine that was used to pump water out of tin mines in Cornwall.

The Scottish inventor James Watt (1736-1819) realised that most of the heat used to make the steam was being wasted in heating and re-heating the iron cylinder and piston.

He invented a separate condenser, which was a sealed container connected to the cylinder by a pipe. After the piston had drawn steam into the cylinder, water was sprayed into the condenser rather than the cylinder, so the engine worked as before, but the cylinder and piston remained hot. He patented this and several other improvements, and patented (received exclusive rights to make, use, and sell) his own engine in 1769. The engine was very successful because it used as little as a quarter of the wood or expensive coal to produce the same amount of work as Newcomen's engine. He is usually considered to be the father of the steam engine, although he thought the use of high-pressure steam (as used in later engines) to be dangerous, as in fact it tended to be, with the relatively crude cast-iron engineering of the time.

The inventor of what we consider today to be a "steam engine", that is an engine where the pressure of the steam pushes the piston and does the work, was the mining engineer Richard Trevithick (1771 - 1833). A major advantage of his high-pressure engine was that it operated at a much higher speed than the older condensing engine. This made steam-powered vehicles a reality, and he went on to build a steam-powered carriage, and later in 1804 his steam locomotive became the first in the world to pull a heavy load - over a distance of almost 10 miles.

There have been many contributors to the invention of the steam engine and making the steam engine important during the industrial revolution.