For many years water was the only significant source of power to drive machinery. Mills were driven by a wheel, powered by the flow of a stream running past and turning the mechanism. It was not until the late 17th century when Thomas Savery, a military engineer, devised a system that he called the “atmospheric engine” that powerful pumps were available. Pumps were needed to raise water from mines to prevent flooding. By pumping out ground water it was possible to reach much lower depths and exploit new mineral veins.
Savery used atmospheric pressure to drive his pump by filling the cylinder with steam then rapidly cooling it by running water over the surface of the engine. The steam quickly condensed with a massive reduction of pressure that pulled water out of the mine shaft. The system was inefficient and dangerous because it was liable to explode, so blacksmith Thomas Newcomen designed a new version that was more reliable and it was first installed in the Earl of Dudley’s limestone mines below Dudley Castle (West Midlands) in 1712.
Newcomen’s engine was heavy and slow, but efficient, and it was adopted by mines all over the UK but in 1765 Scottish instrument maker James Watt realised that cooling the steam for each engine stroke wasted energy. He devised a way to keep the steam hot and to shift it to opposite sides of a piston and so produced an engine that had a powerful double stroke. His early efforts were dogged by technical difficulties but he was eventually taken on by Birmingham ‘toy’ manufacturer Matthew Boulton who created the massive Soho Foundry so that Watt could perfect his machine.
Watt later developed an addition to his engine that enabled the straight stroke of the piston to be turned to circular motion. The rotary adapter revolutionised industry and made it possible for the first time to drive production machinery by steam. The Industrial Revolution finally had a power source equal to the ideas of its leaders and factories sprang up all over the country to manufacture goods. Formerly cottage industries were moved to centres of mass production with the mechanisation of all kinds of crafts from spinning and weaving to pottery and metalwork.