"A semicircular protractor by Lenoir with 3-inch radius divided in degrees and half degrees with alidade bearing a vernier that provides readings to an arcminute. This instrument has its own wooden case," reads Ceschi’s 1843 inventory.
Signed Lenoir a Paris, the instrument is preserved in its wooden case, the same shape as the protractor.
The same 1843 inventory tells us that the Specola also possessed by the same craftsman "An ebony ruler made by Lenoir on which is marked the half meter and the foot of Paris" and "Two ebony rulers by Lenoir with a silver plate on which is marked the exact quarter of a meter and inches". These three rulers have not been found.
For the life and work of Lenoir, considered one of the best instrument makers of the period, see file 83 on the reflecting circle and the cited works of Daumasand Bennett.

J.A. Bennett (1989).
M. Daumas (1953), pp.245, 268, 363.
A.J. Turner (1989)