KTESIBY (Ktesibios)

Ktesiby; Ktesibios, of Alexandria, the first half of III. BC. e., Greek writer and mechanic. Constructed a set of machines and tools, working on the principle of compressed air, such as a weapon for throwing nuclei, the so-called aeroton, siege machines, water body, water clocks, water machine for churches and t. d. Idea to. later used Philo of Byzantium, and Heron of Alexandria. In the essay Notes (Hypomnemata), of which only excerpts have survived Vitruvius, K. expounded the principles of pneumatics, referring to the teachings of Strato Lampsak.