The Bruce Medalists


  portrait Photo 1896, courtesy Mary Lea Shane Archives, Lick Observatory
David Gill
12 June 1843 1900 Bruce Medalist 24 January 1914

David Gill, a Scotsman, trained as a watchmaker and worked in that profession. Timekeeping led to astronomy, and he designed, equipped, and operated a private observatory at Dun Echt near Aberdeen for James Lindsay, the Earl of Crawford. In 1877 Gill and his wife travelled to Ascencion Island to measure the solar parallax by observing Mars. After he proved the worth of the heliometer, a telescope with a divided objective, for measuring the distance to the sun, he was appointed Her Majesty's Astronomer at the Cape of Good Hope, a position he held from 1879 to 1906. He greatly improved the observatory, designing and securing new instruments of unprecedented precision. He redetermined the distance to the sun to such precision that his value was used for almanacs until 1968. He photographed the southern sky and helped initiate the international Carte du Ciel project to chart the entire sky. Gill and Jacobus C. Kapteyn, who measured Gill's photographs in the Netherlands, initiated the separation of observation from reduction. Gill also made geodetic surveys of South Africa. In fact he carried out all of the observations to measure the distances to stars in terms of the standard meter.

Presentation of Bruce medal
Pardee, George C., PASP 12, 49-55 (1900).

Other awards
Government of Germany, Order Pour le Merite for Arts and Sciences, 1910.
National Academy of Sciences, James Craig Watson Medal, 1899.
Royal Astronomical Society, Gold medal, 1882, 1908, presented by H.F. Newall, MNRAS 68, 317-30 (1908).
Royal Society, Royal Medal, 1903.

Some offices held
Royal Astronomical Society, President, 1909-11.

Biographical materials
Astronomical Society of Southern Africa
Bitterman, Jay, Lake County Astronomical Society
Forbes, George, David Gill: Man and Astronomer (John Murray, London, 1916).
Reid, John S., “Sir David Gill – Scotland’s most notable astronomer?”, The Conversation, 2014.
Reid, John, “David Gill - Magnificent and Desirable Astronomer,” presentation at the International Conference on the History of Physics held at Trinity College, Cambridge, in September 2014. arXive:1601.02519.
Stoy, R.H., Dictionary of Scientific Biography 5, 403-06.
Tenn, Joseph S., “David Gill: The Third Bruce Medalist,” Mercury 19, 3, 84 (1990).
Warner, Brian, “Sir David Gill (1843–1914)," Transactions of the Royal Society of South Africa 49, 147-53 (1994).
University of Aberdeen

Anonymous, Observatory 37, 115-17 (1914).
Dyson, F.W., Proceedings of the Royal Society A 91, xxvi-xlii (1914-15).
E[ddington], A.S., MNRAS 75, 236-47 (1915).
Kapteyn, J.C., Ap.J. 40, 161-72 (1914).
Paterson, John A., JRASC 13, 343-59 (1919).
More obituaries

Astronomical Society of Southern Africa (several)
David and Isobel Gill at Mars Bay, Ascension, 1877, where Gill was observing the opposition of Mars in order to measure the solar parallax. From George Forbes, David Gill: Man and Astronomer (London, 1916), facing p. 94. (sketch)
Royal Astronomical Society/Science Photo Library (several)
Stamps from Ascension Island commemorating the centenary of the Gills’ visit
University of Aberdeen Natural Philosophy Collection

Named after him
Lunar crater Gill
Martian crater Gill
Minor Planet #11761 Davidgill
Astronomical Society of Southern Africa, Gill Medal

More references

The Bruce Medalists

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