Physical description

A scale rule used by artillery units to measure distance between map co-ordinates on the 1 to 25,000 scale military map series.
The rule is accurately machined from flat stainless steel strip and is stamped with Imperial measurements (thousands of yards) and metric measurements (thousands of metres).

Inscriptions & markings

The rule is stamped with the following: "SCALE, ARTY, No 2, MKI, E.ESDAILE & SONS, D^D, 1942"