FRANCE, last third of the 18th century Large brass pinnacle graphometer. The plate is openwork with foliate scrolls, the blade engraved with a double 180° scale with counter-reading, a mobile alidade and centered with a gilded compass with eight directions. Signed and dated "CANIVET à La Sphère à Paris - 1770" above the limb. Ball joint socket. L. 28.9 cm. Some wear and scratches; leprosy on the compass glass; old pitting and spots of oxidation, notably at the bases of the alidade pinnules. Jacques CANIVET, received his master's degree in Paris on January 30, 1743. From 1747, he set up shop on the Quai de l'Horloge in Paris, under the sign "A la Sphère. Nephew and successor of Claude Langlois, Canivet invented a new form of pantograph. This enabled him to become "Ingénieur du Roi" and "de l'Académie des Sciences" in 1756. A famous instrument manufacturer, he supplied several large sextants and quarter-circles to observatories in Paris, Colombes, Milan and Vilna. He ceased trading in 1774.