Ctesibius (working 285 - 222 BC) of Alexandria was second only to Archimedes as an inventor and mathematician. His lost work on the elasticity of air On pneumatics still earns him the title of father of pneumatics, for the first treatises on the science of compressed air and its uses in pumps and even a cannon, are his. Like all his other works, however, it has not survived. Even his Memorabilia, a compilation of his research, cited by Athenaeus, is lost.

Ctesibius was probably the first head of the Museum of Alexandria. Unfortunately, very little is known of his life and work. He is said (by Diogenes Laertius?) to have started life as a barber who made a clever counterweighted adjustable mirror. He invented a water organ and an improvement on the water clock, called a clepsydra, that kept more accurate time than any clock invented until the 17th century, when the Dutch physicist Christiaan Huygens showed how a pendulum could be used to regulate a clock. The principle of the siphon has been attributed to him.

In his age Ctesibius was miserably poor, if Diogenes Laertius can be trusted, who recounts how the generous philosopher Arcesilaus, "when he had gone to visit Ctesibius who was ill, seeing him in great distress from want, he secretly slipped his purse under his pillow; and when Ctesibius found it, 'This,' said he, 'is the amusement of Arcesilaus.'" [1]

His work is chronicled by Vitruvius, Athenaeus,and Philo of Byzantium who repeatedly mentions him, adding, with an almost audible sigh, that the first mechanicians had the advantage of being under kings who loved fame and supported the arts. Proclus, the commentator on Euclid, and Hero of Alexandria, the last of the engineers of antiquity, also mention him.

External link

• Ancient Greek Scientists: Ctesibius