Geodesy Circle With Two Glasses By Rochette, C. 1820

Brass geodesic circle with two bezels signed "Rochette Quai de l'Horloge à Paris". This is Gaspard Rochette who was active on Quai de l'Horloge from 1794 to his death in 1846. We more commonly find the signature of his son Jean Rochette who signs "Rochette jeunesse". The glasses measure 29.5cm in length and the main circle 23.5cm in diameter. It is divided into 360th degrees on a silver limb and features a micrometric adjustment. The second bezel has two micrometric adjustments and the whole thing is mounted on a circle placed on three calente screws. Good working condition and good condition of the period varnish. Overall measurement 25x30cm.