Biographies

Sir Charles Algernon Parsons (1854-1931) was a British engineer who perfected the steam turbine that bears his name.

Charles Parsons was born on June 13, 1854, in London. His father, William Parsons, 3d Earl of Rosse, was a distinguished astronomer and sometime president of the Royal Society. Charles and his brothers were tutored by eminent scholars working in his father's observatory at Birr Castle, Parsonstown (now called Birr), in King's County, Ireland (Offalay, Eire). He attended Trinity College, Dublin (1871-1873), and Cambridge University (1873-1877), where he distinguished himself in mathematics. He then worked at the Armstrong engineering works located at Newcastle-upon-Tyne (1877-1881).

In 1884 Parsons joined a Gateshead partnership and entered the new field of electrical engineering. The production of cheap electricity in quantity demanded prime movers with outputs and efficiencies high above those of reciprocating engines. Thus Parsons developed the steam turbine, a machine with a long conceptual but no practical history. Stream freely expanding from high to low pressures acquires velocity and may form a jet which can impinge on a turbine wheel and yield useful work. But to get the most out of a high-pressure jet, a singlestage turbine would have to rotate at speeds above the capacities of materials then available. By setting a series of turbine wheels on one shaft and limiting the pressure drop between adjacent wheels, Parsons was able to reduce shaft and peripheral speeds to acceptable limits. By allowing steam to expand across the turbine blades, he was able to improve performance further; and by introducing the steam between a pair of coupled but opposed turbine sets, he avoided thrusts on the end bearings. He patented these and other innovations in 1884.

Electric generators then worked at about 1,500 revolutions per minute (rpm), while Parsons' turbine worked at 18,000 rpm. Undaunted, he designed and built a generator suitable for direct coupling. Thus, the turboalternator was born, and by 1889 several hundred were in use, mostly for ship lighting. That year Parsons set up his own works in Newcastle, concentrating at first on large turboalternators for urban electricity supplies.

In 1894 Parsons turned to the marine applications of the steam turbine and built the Turbinia, 100 feet long and displacing 44 tons. After many experiments with screw designs, it reached speeds of 34 knots in 1897. Despite initial apathy, the turbine became standard in British warships from 1905. For fast liners the turbine soon proved its economy; and with Parsons' development of suitable gear trains, the reciprocating engine was displaced from many slower ships. He was knighted in 1911, and he died on Feb. 11, 1931, in Kingston, Jamaica.

Further Reading

• A biography of Parsons is Rollo Appleyard, Charles Parsons: His Life and Work (1933). A booklet by Robert Hodson Parsons, The Steam Turbine and Other Inventions of Sir Charles Parsons (1942; rev. ed. 1946), is useful. The historical scene and background are set out in Henry Winram Dickinson, A Short History of the Steam Engine (1938; 2d ed. 1963).