A rare French WW1 period aircraft altimeter, circa 1915. The instrument is particularly fine in both construction and appearance.
It retains the original leather outer case, and also four small rings used to secure the altimeter into a sprung cradle. Most British altimeters were fitted directly to the instrument panel, French instruments were sprung to alleviate vibration caused by the engine.
The instrument can be set for altitude and reacts to atmospheric pressure variations.
This Early WW1 Altimeter Is Very Rare