Brass graphometer. Epoque nineteenth.
Signed Henri PINARD Const 'Quai Napoléon 21 PARIS
Ladder twice 180 ° divided at ten minutes by transverse.
Total height19cm
Width 22.2cm
The graphometer is an old angle measurement instrument. Mounted on a ball joint, it makes it possible to "take" angles between objects located in the same plane. It is an instrument of geodesy and topography.