As a young scientist-engineer, Galileo wrote two manuscripts on motion. The first, Delle macchine, written ca. 1592; reflected the tradition of Aristotle’s Mechanics. It was never printed. The second, revised study, Le mechaniche, written ca. 1598, depended more upon Archimedes and Guidobaldo than Aristotle. It remained in manuscript form until Mersenne printed this first edition in Paris. A few years later, in the Discourse on Two New Sciences, Galileo published his mature thoughts on physics, superseding these early studies. The Discourse (1638) is on display at the Sam Noble Oklahoma Museum of Natural History.