First edition, third state of the first modern survey of any portion of England, undertaken by the Ordnance Survey, under the direction of William Mudge.
This edition can be determined by the inclusion of the Royal Military Canal (completed in 1809) on the Southeast Sheet.
William Mudge (1762-1820) was an English artillery officer and Surveyor. He entered the Royal Military Academy, Woolwich in 1777. In July 1779 he received a commission as second lieutenant in the Royal Artillery, and was sent to South Carolina to join the army under Charles Cornwallis, 1st Marquess Cornwallis. He was promoted first lieutenant on 16 May 1781. On his return home he was stationed at the Tower of London, and studied the higher mathematics under Charles Hutton. He was appointed in 1791 to the Ordnance Trigonometrical Survey, of which he was promoted to be director on the death of Colonel Edward Williams in 1798. He was elected a Fellow of the Royal Society the same year.
Around 1800, Dunnose was taken as a base point for a triangulation of Great Britain, in which Mudge measured a section of the meridional arc running up into Yorkshire. The triangulation was conducted in 1801 and 1802. The positions of twenty three points between Dunnose and Beacon Hill, Clifton, near Doncaster, were determined, and the closest possible measurements were made of the distances between the points and the direction from one point to another. Doubts were cast on the accuracy of the measurements in 1812, when Joseph Rodriguez pointed out that, if they were accurate, the length of a degree of longitude did not vary with latitude as it should if the earth were flattened at the poles.
Mudge was promoted brevet major in September 1801, regimental major in September 1803, and lieutenant-colonel in July 1804. While at the head of the survey he resided first, until 1808, at the Tower of London, and afterwards at 4 Holles Street, London, which he purchased; there he resided for the rest of his life.