He entered the Royal Military Academy, Woolwich, on 17 April 1777, and while he was there his godfather, Samuel Johnson, paid him a visit, and gave him a guinea and a book.

[1] On his return home he was stationed at the Tower of London, and studied the higher mathematics under Charles Hutton, amusing himself in his spare time with the construction of clocks.

[1] 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.

[5] 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.

On the extension of the English arc of the meridian into Scotland, the French Bureau des Longitudes applied for permission for Jean-Baptiste Biot to make observations for them on that line.

James Satterthwaite the story of the surveyor (identified with Mudge) on top of Black Combe, famous for its long-distance views inland and out to sea, who was not able to see even the map in front of him when fog or darkness closed in.