Thomas Frederick Colby

Thomas Frederick Colby FRS FRSE FGS FRGS (1 September 1784 – 9 October 1852), was a British major-general and director of the Ordnance Survey (OS). A Fellow of the Royal Astronomical Society and Royal Society, Colby was one of the leading geographers of his time.

Thomas Colby, 1837 drawing by William Brockedon

An officer in the Royal Engineers, Colby overcame the loss of one hand in a shooting accident to begin in 1802 a lifelong connection with the Ordnance Survey. His most important work was the Survey of Ireland. He began planning this enormous enterprise in 1824 and directed it until 1846, in which year the final maps made by the survey were almost ready for issue. He was the inventor of the "Colby Bar" (a compensation bar), an apparatus used in base-measurements.[1]

  1. ^  One or more of the preceding sentences incorporates text from a publication now in the public domainChisholm, Hugh, ed. (1911). "Colby, Thomas Frederick". Encyclopædia Britannica. Vol. 6 (11th ed.). Cambridge University Press. p. 660.