Ctesibius or Ktesibios or Tesibius (Greek : Κτησίβιος; fl. 285–222 BC) was a Greek inventor and mathematician in Alexandria, Ptolemaic Egypt. 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 the elasticity of air On pneumatics, 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.
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) that his first career was as a barber. During his time as a barber, he invented a counterweight-adjustable mirror. Another invention of his included the hydraulis, a water organ that is considered the precursor of the modern pipe organ, of which he and his wife Thais were highly reputed players.He improved the water clock or clepsydra ("water thief"), which for more than 1,800 years the clepsydra 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.
According to Diogenes Laërtius, Ctesibius was miserably poor. Laërtius details this by recounting the following concerning the 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."
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 (the last of the engineers of antiquity) also mention him.
Anacharsis was a Scythian philosopher; he travelled from his homeland on the northern shores of the Black Sea, to Athens, in the early 6th century BC, and made a great impression as a forthright and outspoken barbarian, that is, a non-Greek speaker. He very well could have been a forerunner of the Cynics, in part because of his strong, but playful, parrhesia. None of his works have survived.
Empedocles was a Greek pre-Socratic philosopher and a native citizen of Akragas, a Greek city in Sicily. Empedocles' philosophy is best known for originating the cosmogonic theory of the four classical elements. He also proposed forces he called Love and Strife which would mix and separate the elements, respectively.
Hero of Alexandria was a Greek mathematician and engineer who was active in his native city of Alexandria, Roman Egypt. He is often considered the greatest experimenter of antiquity and his work is representative of the Hellenistic scientific tradition.
Arcesilaus 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 Academy in which it embraced philosophical skepticism.
Menippus of Gadara was a Cynic satirist. The Menippean satire genre is named after him. His works, all of which are lost, were an important influence on Varro and Lucian, who ranks Menippus with Antisthenes, Diogenes, and Crates as among the most notable of the Cynics.
Demetrius of Phalerum was an Athenian orator originally from Phalerum, a student of Theophrastus, and perhaps of Aristotle, and one of the first Peripatetics. Demetrius was a distinguished statesman who was appointed by the Macedonian king, Cassander, to govern Athens, where he ruled as sole ruler for ten years, introducing important reforms of the legal system while maintaining pro-Cassander oligarchic rule. He was exiled by his enemies in 307 BC, and he went first to Thebes, and then, after 297 BC, to the court of Alexandria. He wrote extensively on the subjects of history, rhetoric, and literary criticism. He is not to be confused with his grandson, also called Demetrius of Phaleron, who probably served as regent of Athens between 262 and 255, on behalf of the Macedonian King Antigonos Gonatas.
A water clock or clepsydra is any timepiece by which time is measured by the regulated flow of liquid into or out from a vessel, and where the amount is then measured.
Lacydes of Cyrene, Academic Skeptic philosopher, was head of the Platonic Academy at Athens in succession to Arcesilaus from 241 BC. He was forced to resign c. 215 BC due to ill-health, and he died c. 205 BC. Nothing survives of his works.
An aeolipile, aeolipyle, or eolipile, also known as a Hero's engine, is a simple, bladeless radial steam turbine which spins when the central water container is heated. Torque is produced by steam jets exiting the turbine. The Greco-Egyptian mathematician and engineer Hero of Alexandria described the device in the 1st century AD, and many sources give him the credit for its invention. However, Vitruvius was the first to describe this appliance in his De architectura.
Philo of Byzantium, also known as Philo Mechanicus, was a Greek engineer, physicist and writer on mechanics, who lived during the latter half of the 3rd century BC. Although he was from Byzantium he lived most of his life in Alexandria, Egypt. He was probably younger than Ctesibius, though some place him a century earlier.
Timon of Phlius was a Greek Pyrrhonist philosopher, a pupil of Pyrrho, and a celebrated writer of satirical poems called Silloi (Σίλλοι). He was born in Phlius, moved to Megara, and then he returned home and married. He next went to Elis with his wife, and heard Pyrrho, whose tenets he adopted. He also lived on the Hellespont, and taught at Chalcedon, before moving to Athens, where he lived until his death. His writings were said to have been very numerous. He composed poetry, tragedies, satiric dramas, and comedies, of which very little remains. His most famous composition was his Silloi, a satirical account of famous philosophers, living and dead; a spoudaiogeloion in hexameter verse. The Silloi has not survived intact, but it is mentioned and quoted by several ancient authors. It has been suggested that Pyrrhonism ultimately originated with Timon rather than Pyrrho.
The water organ or hydraulic organ is a type of pipe organ blown by air, where the power source pushing the air is derived by water from a natural source or by a manual pump. Consequently, the water organ lacks a bellows, blower, or compressor.
De architectura is a treatise on architecture written by the Roman architect and military engineer Marcus Vitruvius Pollio and dedicated to his patron, the emperor Caesar Augustus, as a guide for building projects. As the only treatise on architecture to survive from antiquity, it has been regarded since the Renaissance as the first book on architectural theory, as well as a major source on the canon of classical architecture. It contains a variety of information on Greek and Roman buildings, as well as prescriptions for the planning and design of military camps, cities, and structures both large and small. Since Vitruvius published before the development of cross vaulting, domes, concrete, and other innovations associated with Imperial Roman architecture, his ten books give no information on these hallmarks of Roman building design and technology.
Phaenias of Eresus was a Greek philosopher from Lesbos, important as an immediate follower of and commentator on Aristotle. He came to Athens about 332 BCE, and joined his compatriot, Theophrastus, in the Peripatetic school. His writings on logic and science appear to have been commentaries or supplements to the works of Aristotle and Theophrastus. He also wrote extensively on history. His works have only survived in fragments quoted by other authors.
Sotion of Alexandria was a Greek doxographer and biographer, and an important source for Diogenes Laërtius. None of his works survive; they are known only indirectly. His principal work, the Διαδοχή or Διαδοχαί, was one of the first history books to have organized philosophers into schools of successive influence: e.g., the so-called Ionian School of Thales, Anaximander and Anaximenes. It is quoted very frequently by Diogenes Laërtius, and Athenaeus. Sotion's Successions likely consisted of 23 books, and at least partly drew on the doxography of Theophrastus. The Successions was influential enough to be abridged by Heraclides Lembus in the mid-2nd century BC, and works by the same title were subsequently written by Sosicrates of Rhodes and Antisthenes of Rhodes.
Polemon of Athens was an eminent Platonist philosopher and Plato's third successor as scholarch from 314/313 to 270/269 BC. A pupil of Xenocrates, he believed that philosophy should be practiced rather than just studied, and he placed the highest good in living according to nature.
Heraclides Lembus was an Ancient Greek statesman, historian and philosophical writer.
Sphaerus of Borysthenes or the Bosphorus, was a Stoic philosopher.
Apollodorus of Cyzicus can refer to two different persons from ancient Greece:
The Hydraulis of Dion is a unique exhibit of the Archaeological Museum of Dion. It is the oldest instrument of that type discovered so far.