Catalogue description Ordnance Survey: Trigonometrical and Levelling Divisions: Levelling Heighter Lists

Records from the Primary, Second and Third Order Geodetic levelling of Great Britain by the Ordnance Survey 1840-1968.

The lists contain descriptions and heights of all bench marks, given in levelling line order and to 3 or 4 decimal places. The series also includes detail pamphlets, created in the field and recording extra bench marks not included in the abstracts nor in the modern electronic database currently in use at the Ordnance Survey.

Ordnance Survey of Great Britain, Directorate of Field Survey, 1946-1973

Ordnance Survey, Control and Trigonometrical Division, 1925-1930

Ordnance Survey, control, trigonometrical and levelling branches, 1791-1925

Ordnance Survey, Levelling Division, 1925-1934

Ordnance Survey, Trigonometrical and Levelling Division, 1935-1946