CLERGET, à Paris Openwork brass graphometer with compass and pinnules, engraved with leaves and flowers, on a ball-and-socket joint with heart-shaped key. Signed. Second half of the 18th century. Length: 23.7 cm. Missing wires. Wear, scratches and minor wear bumps; oxidation stains on reverse. In a (later) walnut and steel case, with one side handle (stains, scratches, bumps and a few cracks).