Ctesibius

Chambers's Encyclopaedia, Volume 3: Catarrh to Dion, p. 603

Ctesibius, a Greek who flourished under Ptolemy Philadelphus and Euergetes, at Alexandria, about 250 years B.C., and was famous for his inventions in mechanics. We owe to him and his pupil Hero Alexandrinus, the pump, the bent siphon, and also the discovery of the elastic force of air, and its application as a motive power.

Source scan(s): p. 0614