A fuse height indicator converted a target's range into a fuse length. This allowed gunners to set shell fuses to explode at the correct position over a designated target. Errors in calculating range would result in shells exploding too early or too late, leaving the target unaffected by the bombardment.
MK I No. 1 Height and Fuze Indicating Instrument
CWM 19390002-175
Canada and the First World War
