Steam Engines

Although steam engines had been in existence for some time, it was James Watt who made a breakthrough in the process and the age of steam truly got underway.

In the 1700s, steam was used to remove water from the mines, although this was a far cry from the powerful steam-powered engines which developed later.

The first steam pump was invented by Thomas Savery in 1698 and his vacuum pump replaced animal labour which had been used to draw water from the mines up until that time.

Steam power is based on the principle that the condensation of water vapour creates a vacuum. Although it was more efficient than animal power, the vacuum pump could only lift water from depths of around 80 feet and secondly, boiler explosions were not uncommon. This first steam engines required vast quantities of steam as they cooled at every stroke.

Thomas Newcomen worked on Savery's patent to improve the original idea by using atmospheric pressure. However they were still inferior to James Watt's invention.

In 1765, Watt went on to invent a separate condenser when he was just 29. Financed by Matthew Boulton, it took another 11 years before Watt's idea was implemented.

Watt's engine operated on the principle of the steam piston being pulled down by the vacuum. His design also allowed the steam cylinder to retain its heat throughout the cycle making it more efficient, unlike its forerunners. Valves allowed the steam to be sucked into a separate condenser and then pumped along with the air pump.

Soon this new engine technology was applied to other uses beyond just pumping the mines. By 1800 Boulton and Watt engines were used in 84 cotton mills and factories which were rapidly developing during the Industrial Revolution.

Watt then devised a mechanism for the piston to work up and down while the parallel motion beam worked in an arc. Steam was used to propel the piston by pushing it, rather than the old methods which used the vacuum to pull it.

Finally a speed control was developed, connected to the throttle valve. Watt eventually retired in 1800 and died in 1819, satisfied with his life's achievements.

For steam engine enthusiasts, restored steam engines are now an interesting part of the exhibits on display at Bressingham Steam and Gardens, the Colne Valley Railway and Museum at Castle Hedingham and the Kew Bridge Steam Museum in Brentford.