Ctesibius

{{Short description|3rd-century BC Greek inventor and mathematician}}

{{About|the inventor and mathematician|the lunar crater|Ctesibius (crater)|the beetle genus|Ctesibius (beetle)}}

{{Infobox scientist

| name = Ctesibius

| birth_date = {{circa|300}}

| birth_place =

| death_date = {{circa|222|lk=no}} BCE

| death_place = Alexandria, Egypt

| nationality = Alexandrian Greek

| fields = Mathematics

}}

File:ARAGO Francois Astronomie Populaire T1 page 0067 Fig16-17.jpg]]

Ctesibius or Ktesibios or Tesibius ({{langx|grc|Κτησίβιος}}; {{fl|285–222}} BCE) was a Greek inventor and mathematician in Alexandria, Ptolemaic Egypt.{{cite encyclopedia|encyclopedia=Encyclopædia Britannica|url=https://www.britannica.com/biography/Ctesibius-of-Alexandria |title= Ctesibius of Alexandria |quote= Greek physicist and inventor, the first great figure of the ancient engineering tradition of Alexandria, Egypt. |orig-date= First published online July 1998|date=February 2024}} Very little is known of Ctesibius' life, but his inventions were well known in his lifetime. He was likely the first head of the Museum of Alexandria. He wrote the first treatises on the science of compressed air and its uses in pumps (and even in a kind of cannon). This, in combination with his work On pneumatics on the elasticity of air, earned him the title of "father of pneumatics." None of his written work has survived, including his Memorabilia, a compilation of his research that was cited by Athenaeus. Ctesibius' most commonly known invention today is a pipe organ (hydraulis), a predecessor of the modern church organ.

Inventions

Ctesibius was the son of a barber, born {{circa|300}} BCE, probably{{snd}}but not certainly{{snd}}in Alexandria.{{efn|There is no direct evidence for the place of birth of Ctesibius. He is given {{lang|la|Alexandrinus}}, {{lit|the Alexandrian}}, as "an ethnic" or "a deme" (the element in traditional Greek onomastic formulae ascribing geographic or ethnic origin),{{cite book|last1=Rizakis |first1=Athanasios |editor1=Robert Parker |title=Changing Names: Tradition and Innovation in Ancient Greek Onomastics |date=April 2019 |publisher=British Academy |isbn=978-0-19-188424-5 |url-access= subscription|url=https://academic.oup.com/british-academy-scholarship-online/book/37130 |language=en |chapter=New Identities in the Greco-Roman East: Cultural and Legal Implications of the Use of Roman Names |doi=10.5871/bacad/9780197266540.003.0011 |pages=237–257}} in early mentions and reference to his work, including by Vitruvius ({{BCE|1st century}}) in {{lang|la|De Architectura}}.{{cite book |author =Vitruvius |title=De Architectura |at= Book IX, Chapter 8.2}}}}{{cite encyclopedia |last1=Hoffmann |first1=James J. |editor1=Neil Schlager |others=Associate editor: Josh Lauer |title=Ctesibius of Alexandria |date=2001 |pages=400–401 |url=https://archive.org/details/B-001-002-827/page/n373/mode/2up |encyclopedia =Science and Its Times: Understanding the Social Significance of Scientific Discovery |volume =1 2000 BC to AD 699|publisher=Gale Group|quote=Ctesibius (also spelled Ktesibios) was a Greek physicist and inventor who was probably born in Alexandria sometime around 300 B.C. He was the first of many Greeks to become part of the great ancient engineering tradition in Alexandria.}}{{cite book |last1=Pollard |first1=Justin |last2=Reid |first2=Howard |page=130 |title=The Rise and Fall of Alexandria: Birthplace of the Modern World |date=2007 |publisher=Penguin Books |isbn=978-0143112518 |chapter=The Clockwork City}} He began his career as a barber, following his father.

File:Hydraulis organ of Ctesibius.jpg, in Athens, Greece.]]

During this first career, he invented a counterweight-adjustable mirror. Another of his inventions was the hydraulis, a water organ that is considered the precursor of the modern pipe organ and the first keyboard instrument. He and his wife Thais were reputed to be highly-skilled players of the instrument.Athenaeus Deipnosophistae 4.174e{{Cite book|last=Leon|first=Vicki|title=Uppity Women of Ancient Times|publisher=Conari Press|year=1995|isbn=9781573240109|pages=82}} He improved the water clock or clepsydra ('water thief'), which for more than 1,800 years was the most accurate clock ever constructed, until the Dutch physicist Christiaan Huygens' invention of the pendulum clock in 1656. Ctesibius described one of the first force pumps for producing a jet of water, or for lifting water from wells. Examples have been found at various Roman sites, such as at Silchester in Britain. The principle of the siphon has also been attributed to him.

File:Ctesibius's_water_clock,_3rd_century_BC,_Alexandria_(reconstruction).jpg]]

Reputation

According to Diogenes Laërtius, Ctesibius was miserably poor. Laërtius details this by recounting the following concerning the philosopher Arcesilaus:

{{blockquote|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."}}

Ctesibius's work is chronicled by Vitruvius, Athenaeus, Pliny the Elder, 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 (the commentator on Euclid) and Hero of Alexandria also mention him.

Commemoration

In 1976, the crater on the far side of the Moon was named Ctesibius by the International Astronomical Union.{{gpn|1344}}

Notes

File:A reconstruction of the counterweight-adjustable mirror of Ctesibius, Kotsanas Museum of Ancient Greek Technology.jpg, Athens, Greece.]]

Ctesibius

Inventions

Reputation

Commemoration

Notes

References

Further reading