Sir George Biddell Airy

Sir George Biddell Airy 1801-92, English astronomer. The son of a poor farmer, he distinguished himself as Senior Wrangler at Cambridge, where he was elected fellow of Trinity College (1824) and appointed professor (1826). As Astronomer Royal and director of the Royal Greenwich Observatory from 1835 to 1881, he organized the efficient and accurate observation of stellar positions. Airy wrote many governmental reports on astronomical and other subjects, published works on celestial mechanics, and made discoveries in theoretical and practical optics, including the cylindrical lens for correcting astigmatism, an eye defect he himself possessed.

Bibliography: See his autobiography (1896).

Airy, Sir George Biddell (1801–92) Sir George Airy, who was Astronomer Royal for 46 years, is best known among Earth scientists for his contributions to the theory of isostasy (or ‘crustal balance’ as it was then termed) and for the experiments he carried out to measure the density of the Earth.

Airy began his career as a mathematician, and he was elected to the Lucasian Chair of Mathematics at Cambridge in 1826. He held that post for only two years before being elected Plumian Professor of Astronomy and Director of the Cambridge Observatory in 1828. His textbook on physical astronomy had been published in 1826. Airy was appointed Astronomer Royal in 1835, and displayed great energy in that role. Among other things he re-equipped the Greenwich observatory with new instruments (which he designed himself), he created a magnetic and meteorological department, and he made important contributions to celestial mechanics. In 1894 he supervised a series of pendulum experiments with the object of measuring the increase in gravity with depth below the surface of the Earth. He was a prolific author, who published works on gravitation and on the downward extension of mountain roots, on the figure of the Earth, and on tides and waves as well as on astronomical subjects. Airy was characterized by thoroughness in his investigations and by his efficiency and strict discipline as an administrator.

D. L. Dineley

Airy, George Biddell (1801–92) A Cambridge astronomer and mathematician, Airy became Astronomer Royal in 1835. He investigated planetary motion and tides, and studied the Earth and its density, using gravity measurements. His name is used to describe one version of the theory of isostasy. His wide-ranging advice to the government on scientific issues created, for the first time, the role of a professional scientific civil servant.