This compass type was designed by the French officer Paul Peigné. It was built by several companies like MORIN, LADOIS and S-L. A short version of the users' instructions was glued on both sides of the wooden casing (printed by Delagrave et Cie). Late 19th until early 20th century. This compass is equipped with an alidade that could be used both with the compass needle to take azimutal bearings and with the clinometer to measure elevation angles. The magnetic needle oscillations can be slowed by depressing a thin piston gliding through the transit locking screw. The clinometer scale is printed inverted so as to be read in the mirror. It was one of the major official compasses used in the French Army during WWI.
( Text by compassmuseum.com)