At least three manuscripts containing works by Archimedes were composed in Byzantium in the 9th and 10th centuries. Two of these subsequently arrived in the West, spreading knowledge of much of his work. Known to them as "Ersemides" or "Arsamithes," Archimedes was already famous in 10th-century Islamic societies, familiar with his treatises On the Sphere and Cylinder, The Measurement of the Circle, On Plane Equilibria and part of On Floating Bodies. Considered a mathematical point of reference, Archimedes was believed to be the author of numerous other writings and - although they cannot be linked directly to him - their circulation inspired the study of particular problems in geometry. The Islamic civilisations also saw Archimedes as an inventor of extraordinary instruments and mechanical devices, adding the hydrostatic balance and an extremely complex water clock to those known in Antiquity.