Necessity is the Mother of Invention
The arc of development of the technique to harness the properties of steam to power mechanical devices embodies the notion that “necessity is the mother of invention” (Latin: “necessitas ingenium dedit.”)
Towards the end of the 17th century, Britain faced the problem of pumping and draining water out of mine shafts. In response, the military engineer Thomas Savery (1650–1715) invented an “engine to raise water by fire” in 1698. However, the “Savery Pump” was limited in practical usage to 20–25 feet of suction. Savery’s rudimentary pressurized boiler was liable to explode, particularly under high-pressure steam (over 8 to 10 atmospheres.)
Independently, and later in partnership with Savery, blacksmith Thomas Newcomen (1664–1729) developed the more practical—and more successful—atmospheric-pressure piston engine in 1698. Newcomen’s engine solved the limitation of the Savery Pump by having atmospheric pressure push the cylinder’s piston down after the condensation of steam had created a vacuum in the cylinder. Therefore, the pressure of the steam did not limit the intensity of pressure.
For five decades, Newcomen’s engine was the most complex technological object of its time anywhere in the world.
Difficulties Compel People to Found Creative Solutions to Problems
Then came along the Scottish instrument maker James Watt (1736–1819.) At age 21, Watt opened a shop in 1757 at the Glasgow University to make quadrants, compasses, scales, and other mathematical instruments.
Watt was tasked with repairing a Newcomen Engine at the university for a lecture-demonstration. He initially had difficulty getting the Newcomen Engine to work because its parts were poorly constructed. When he finally had it running, he was surprised at its efficiency. However, the engine was constantly running out of coal because every cycle required the heating and the cooling of the cylinder, thus resulting in a large waste of energy.
In 1769, Watt devised a system whereby the cylinder and the condenser were separate, making it unnecessary to heat and cool the cylinder with each stroke. Watt’s invention of the separate-condenser steam engine (also called the “double-acting” steam engine) decreased fuel costs by 75 percent.
Watt’s “steam engine” was able to produce continuous rotary motion and expanded its use far beyond pumping water. Continuous rotary motion sparked the transition from hand-production methods to machine-power and became the driving force of the Industrial Revolution. Playwright George Bernard Shaw even declared in Man and Superman (1903,) “those who admire modern civilization usually identify it with the steam engine.”
The steam engine continued to power industry and transportation during much of the 19th century and early 20th century, at the same time as engineers developed the internal-combustion engine. Towards the end of the 19th century, with the invention of the first practical steam turbine by English engineer Charles Parsons (1854–1931,) turbines started replacing reciprocating steam engines in power stations.
Reference: Richard L. Hills’s Power from Steam: A History of the Stationary Steam Engine (1989.)
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