PURSHALL, Conyers. An Essay at the Mechanism of the Macrocosm; or the Dependance of Effects upon their Causes, in a new Hypothesis, London: printed by F. Collins, for Jeffrey Wale, 1705, 8°, illustrations, contemporary calf (rebacked and worn, first gathering loose, title partially remargined, some light soiling and browning). With George Cheyne's Philosophical Principles of Religion (London, 1736) and Richard Helsham's A Course of Lectures in Natural Philosophy (London, 1755). (3)