CAVALLO, Tiberius. A Treatise of Magnetism, in Theory and Practice, with original Experiment, London, 1795, 8°, second edition with supplement, 6 engraved folding maps, contemporary half calf (joints weak, some light browning and staining, bookplate). [Wheeler 540 (for the London 1787 first edition)] -- Antoine Laurent LAVOISIER. Elements of Chemistry, in a new systematic Order, containing all modern Discoveries, Edinburgh, 1799, 8°, fourth edition, 13 engraved folding plates and 2 folding tables, contemporary calf (rebacked with old spine laid down, browning and staining to plates). With Leonhard Euler's Letters to a German Princess, on different subjects in Physics and Philosophy (2 vols., London, 1795). (4)