Thomas Savery

1650?-1715

English Engineer

Thomas Savery was a military engineer who is known for the invention of the Savery pump. This machine was designed to use steam in order to pump floodwaters from coal mines. While not a steam engine in the modern sense, the Savery pump was the first machine that used steam to provide mechanical power.

Savery was interested in devising mechanisms for practical applications. His significance lies in the extent to which his work serves as a transition from the laboratory-centered experiments of figures such as German physicist Otto von Guericke (1602-1686) and Irish chemist Robert Boyle (1627-1691) to the large-scale mechanical applications that precipitated the Industrial Revolution. Guericke and Boyle developed air pumps and were interested in the properties of gases and the specifics of atomic theory. The enduring image of two teams of horses straining to pull apart Guericke's vacuum-sealed metal hemispheres suggests the quest for the triumph of knowledge over physical force.

Savery, on the other hand, wanted to use scientific knowledge to accomplish tasks beyond the means of brute force. He spent his free time performing mechanical experiments. Indeed, Savery is responsible for inventing a device capable of polishing plate glass as well as a machine that used paddle wheels to move ships stuck in the open water.

His most important invention, which was patented in 1698, was the Savery pump. He designed this machine to lift quantities of water in order to keep mines dry or to supply towns with water. The pump operated according to similar principles that guided the use of vacuums. Savery used steam, and not an air pump, to form a vacuum. Consider, for instance, a chamber filled with steam. If you cooled the outside of the chamber with cold water, the steam within the chamber would condense, leaving only a few drops of water. A vacuum would exist in the place of the steam. If this chamber featured a movable wall, exterior air pressure would drive that wall into the chamber. However, this wall could also be pushed outward again if steam filled the chamber. Then, this wall could be pushed inward if the steam was condensed again. Such a movable wall is, in effect, a piston of the sort that could be used to run a pump. Savery's steam engine relied on high-pressured steam to effect this process. The vacuum then sucked water into a container and out of the coal mine.

Savery's machine was quite unstable, however. The boilers, pipes, and containers were tin soldered and unable to sustain the high pressures necessary to pull water from deep mine shafts. Another Englishman, Thomas Newcomen (1663-1729), was able to devise a steam engine that operated on more stable, low-pressure steam. This new design emerged as the safest and most efficient at the time.

The success of Newcomen and the Scottish engineer James Watt (1736-1819) helped to turn scientific developments into practical achievements. These achievements, and the increasing ease and safety with which they were accomplished, allowed for the transformations engendered by the Industrial Revolution.

DEAN SWINFORD