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).

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.

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.

In December 1803, when on duty at Liskeard, Colby met with an accident through the bursting of a pistol loaded with small shot with which he was practising, his left hand having to be amputated at the wrist and part of the gun being permanently lodged in the skull.

In July 1809, Mudge was appointed lieutenant governor of the Royal Military Academy, Woolwich and Colby became the chief executive officer of the Survey.

[3] In 1813 it was decided to extend the measurement of the meridional line between Dunnose and the mouth of the River Tees into Scotland, with a mineralogical survey being carried out by John MacCulloch.

In that and the following year Colby and his chief assistant, James Gardner, were selecting stations in the south-west of Scotland, and observing from them by theodolite.

When working on remote hills, Colby and his men built structures from local stone or turf to provide shelter.

[5][6][7] Early in 1820 General Mudge died, and the Duke of Wellington appointed Colby to succeed him at the head of the Ordnance Survey.

He was also one of the founders of the Royal Astronomical Society, and with Mark Beaufoy, Olinthus Gregory, Edward Troughton, and others, drew up its rules.

He also decided to have the work carried on under direct official supervision, and raised three companies of sappers and miners to be trained in survey duties.

Colby during its progress introduced electrotyping, contour lines on the six-inch maps, and the training of picked men of the sappers and miners as surveyors.

[3] In 1833, Henry De la Beche suggested a geological map of the west of England, which was handed over by the government to Colby.

The work was proceeding slowly when, in November 1846, just as the sheets of the last Irish county were preparing for issue, Colby attained the rank of major-general, and in accordance with the rule of the service was retired from the post he had so long held.

After his marriage Colby moved from London to Dublin, residing at first in Merrion Square, and afterwards at Knockmaroon Lodge, at the gates of Phoenix Park, within easy distance of the survey office, which was established in the old Mountjoy barracks.