ARAGO Francois Astronomie Populaire T1 page 0067 Fig16-17

Ctesibius or Ktesibios or Tesibius ( grc-gre, Κτησίβιος; fl. 285–222 BC) was a

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

inventor An invention is a unique or novel device, method, composition, idea or process. An invention may be an improvement upon a machine, product, or process for increasing efficiency or lowering cost. It may also be an entirely new concept. If an ...

and

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History On ...

Alexandria Alexandria ( or ; ar, ٱلْإِسْكَنْدَرِيَّةُ ; grc-gre, Αλεξάνδρεια, Alexándria) is the second largest city in Egypt, and the largest city on the Mediterranean coast. Founded in by Alexander the Great, Alexandri ...

, Ptolemaic Egypt. He wrote the first treatises on the science of

compressed air Compressed air is air kept under a pressure that is greater than atmospheric pressure. Compressed air is an important medium for transfer of energy in industrial processes, and is used for power tools such as air hammers, drills, wrenches, an ...

and its uses in pumps (and even in a kind of

cannon A cannon is a large- caliber gun classified as a type of artillery, which usually launches a projectile using explosive chemical propellant. Gunpowder ("black powder") was the primary propellant before the invention of smokeless powder ...

). This, in combination with his work ''On pneumatics'' on the elasticity of air, earned him the title of "father of

pneumatics Pneumatics (from Greek ‘wind, breath’) is a branch of engineering that makes use of gas or pressurized air. Pneumatic systems used in industry are commonly powered by compressed air or compressed inert gases. A centrally located and e ...

." None of his written work has survived, including his ''Memorabilia,'' a compilation of his research that was cited by

Athenaeus Athenaeus of Naucratis (; grc, Ἀθήναιος ὁ Nαυκρατίτης or Nαυκράτιος, ''Athēnaios Naukratitēs'' or ''Naukratios''; la, Athenaeus Naucratita) was a Greek rhetorician and grammarian, flourishing about the end of ...

. Ctesibius' most commonly known invention today is a pipe organ (

hydraulis The water organ or hydraulic organ ( el, ὕδραυλις) (early types are sometimes called hydraulos, hydraulus or hydraula) is a type of pipe organ blown by air, where the power source pushing the air is derived by water from a natural source ...

), a predecessor of the modern church organ.

Inventions

Ctesibius was probably the first head of the Museum of Alexandria. Very little is known of his life, but his inventions were well known. It is said (possibly by

Diogenes Laërtius Diogenes Laërtius ( ; grc-gre, Διογένης Λαέρτιος, ; ) was a biographer of the Greek philosophers. Nothing is definitively known about his life, but his surviving ''Lives and Opinions of Eminent Philosophers'' is a principal sour ...

) that his first career was as a

barber A barber is a person whose occupation is mainly to cut, dress, groom, style and shave men's and boys' hair or beards. A barber's place of work is known as a "barbershop" or a "barber's". Barbershops are also places of social interaction and publi ...

. During his time as a barber, he invented a

counterweight A counterweight is a weight that, by applying an opposite force, provides balance and stability of a mechanical system. The purpose of a counterweight is to make lifting the load faster and more efficient, which saves energy and causes less we ...

-adjustable

mirror A mirror or looking glass is an object that reflects an image. Light that bounces off a mirror will show an image of whatever is in front of it, when focused through the lens of the eye or a camera. Mirrors reverse the direction of the im ...

. Another invention of his included the

, a water organ that is considered the precursor of the modern

pipe organ The pipe organ is a musical instrument that produces sound by driving pressurized air (called ''wind'') through the organ pipes selected from a keyboard. Because each pipe produces a single pitch, the pipes are provided in sets called ''ranks' ...

, of which he and his wife Thais were highly reputed players. He improved the

water clock A water clock or clepsydra (; ; ) is a timepiece by which time is measured by the regulated flow of liquid into (inflow type) or out from (outflow type) a vessel, and where the amount is then measured. Water clocks are one of the oldest time- ...

or clepsydra ("water thief"), which for more than 1,800 years was the most accurate clock ever constructed, until the Dutch

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

Christiaan Huygens Christiaan Huygens, Lord of Zeelhem, ( , , ; also spelled Huyghens; la, Hugenius; 14 April 1629 – 8 July 1695) was a Dutch mathematician, physicist, engineer, astronomer, and inventor, who is regarded as one of the greatest scientists o ...

' invention of the

pendulum clock A pendulum clock is a clock that uses a pendulum, a swinging weight, as its timekeeping element. The advantage of a pendulum for timekeeping is that it is a harmonic oscillator: It swings back and forth in a precise time interval dependent on i ...

in 1656. Ctesibius described one of the first

force pump A piston pump is a type of positive displacement pump where the high-pressure seal reciprocates with the piston. Piston pumps can be used to move liquids or compress gases. They can operate over a wide range of pressures. High pressure operation ...

s for producing a jet of water, or for lifting water from wells. Examples have been found at various Roman sites, such as at

Silchester Silchester is a village and civil parish about north of Basingstoke in Hampshire. It is adjacent to the county boundary with Berkshire and about south-west of Reading. Silchester is most notable for the archaeological site and Roman town of ...

in Britain. The principle of the

siphon A siphon (from grc, σίφων, síphōn, "pipe, tube", also spelled nonetymologically syphon) is any of a wide variety of devices that involve the flow of liquids through tubes. In a narrower sense, the word refers particularly to a tube in a ...

has also been attributed to him. According to

, Ctesibius was miserably poor. Laërtius details this by recounting the following concerning the philosopher

Arcesilaus Arcesilaus (; grc-gre, Ἀρκεσίλαος; 316/5–241/0 BC) was a Greek Hellenistic philosopher. He was the founder of Academic Skepticism and what is variously called the Second or Middle or New Academy – the phase of the Platonic Acad ...

Reputation

Ctesibius's work is chronicled by

Vitruvius Vitruvius (; c. 80–70 BC – after c. 15 BC) was a Roman architect and engineer during the 1st century BC, known for his multi-volume work entitled '' De architectura''. He originated the idea that all buildings should have three attribut ...

Pliny the Elder Gaius Plinius Secundus (AD 23/2479), called Pliny the Elder (), was a Roman author, naturalist and natural philosopher, and naval and army commander of the early Roman Empire, and a friend of the emperor Vespasian. He wrote the encyclopedic ' ...

, and Philo of Byzantium who repeatedly mention him, adding that the first mechanicians such as Ctesibius had the advantage of being under kings who loved fame and supported the arts.

Proclus Proclus Lycius (; 8 February 412 – 17 April 485), called Proclus the Successor ( grc-gre, Πρόκλος ὁ Διάδοχος, ''Próklos ho Diádokhos''), was a Greek Neoplatonist philosopher, one of the last major classical philosophe ...

(the commentator on

Euclid Euclid (; grc-gre, Εὐκλείδης; BC) was an ancient Greek mathematician active as a geometer and logician. Considered the "father of geometry", he is chiefly known for the '' Elements'' treatise, which established the foundations of ...

) and

Hero of Alexandria Hero of Alexandria (; grc-gre, Ἥρων ὁ Ἀλεξανδρεύς, ''Heron ho Alexandreus'', also known as Heron of Alexandria ; 60 AD) was a Greek mathematician and engineer who was active in his native city of Alexandria, Roman Egypt. H ...

(the last of the engineers of antiquity) also mention him.

Inventions

Reputation

References

Further reading