Hero of Alexandria

Hero of Alexandria
[br]
fl. c.62 AD Alexandria
[br]
Alexandrian mathematician and mechanician.
[br]
Nothing is known of Hero, or Heron, apart from what can be gleaned from the books he wrote. Their scope and style suggest that he was a teacher at the museum or the university of Alexandria, writing textbooks for his students. The longest book, and the one with the greatest technological interest, is Pneumatics. Some of its material is derived from the works of the earlier writers Ctesibius of Alexandria and Philo of Byzantium, but many of the devices described were invented by Hero himself. The introduction recognizes that the air is a body and demonstrates the effects of air pressure, as when air must be allowed to escape from a closed vessel before water can enter. There follow clear descriptions of a variety of mechanical contrivances depending on the effects of either air pressure or heated gases. Most of the devices seem trivial, but such toys or gadgets were popular at the time and Hero is concerned to show how they work. Inventions with a more serious purpose are a fire pump and a water organ. One celebrated gadget is a sphere that is set spinning by jets of steam—an early illustration of the reaction principle on which modern jet propulsion depends.
Mechanics, known only in an Arabic version, is a textbook expounding the theory and practical skills required by the architect. It deals with a variety of questions of mechanics, such as the statics of a horizontal beam resting on vertical posts, the theory of the centre of gravity and equilibrium, largely derived from Archimedes, and the five ways of applying a relatively small force to exert a much larger one: the lever, winch, pulley, wedge and screw. Practical devices described include sledges for transporting heavy loads, cranes and a screw cutter.
Hero's Dioptra describes instruments used in surveying, together with an odometer or device to indicate the distance travelled by a wheeled vehicle. Catoptrics, known only in Latin, deals with the principles of mirrors, plane and curved, enunciating that the angle of incidence is equal to that of reflection. Automata describes two forms of puppet theatre, operated by strings and drums driven by a falling lead weight attached to a rope wound round an axle. Hero's mathematical work lies in the tradition of practical mathematics stretching from the Babylonians through Islam to Renaissance Europe. It is seen most clearly in his Metrica, a treatise on mensuration.
Of all his works, Pneumatics was the best known and most influential. It was one of the works of Greek science and technology assimilated by the Arabs, notably Banu Musa ibn Shakir, and was transmitted to medieval Western Europe.
[br]
Bibliography
All Hero's works have been printed with a German translation in Heronis Alexandrini opera quae supersunt omnia, 1899–1914, 5 vols, Leipzig. The book on pneumatics has been published as The Pneumatics of Hero of Alexandria, 1851, trans. and ed. Bennet Wood-croft, London (facs. repr. 1971, introd. Marie Boas Hall, London and New York).
Further Reading
A.G.Drachmann, 1948, "Ktesibios, Philon and Heron: A Study in Ancient Pneumatics", Acta Hist. Sci. Nat. Med. 4, Copenhagen: Munksgaard.
T.L.Heath, 1921, A History of Greek Mathematics, Oxford (still useful for his mathematical work).
LRD

Biographical history of technology. - Taylor & Francis e-Librar. . 2005.

Игры ⚽ Поможем написать реферат

Look at other dictionaries:

  • Hero of Alexandria — Heron Born c. 10 AD Residence …   Wikipedia

  • Hero of Alexandria — (c. ad 62) Greek mathematician and inventor Hero produced several written works on geometry, giving formulae for the areas and volumes of polygons and conics. His formula for the area of a triangle was contained in Metrica(Measurement), a work… …   Scientists

  • Hero of Alexandria — noun Greek mathematician and inventor who devised a way to determine the area of a triangle and who described various mechanical devices (first century) • Syn: ↑Hero, ↑Heron • Instance Hypernyms: ↑mathematician, ↑inventor, ↑discoverer, ↑artificer …   Useful english dictionary

  • Hero the younger — is the name given without any sufficient reason to a Byzantine land surveyor who wrote (about A.D. 938) a treatise on land surveying modelled on the works of Hero of Alexandria, especially the Dioptra. Literature* Geodesie de Heron de Byzance ,… …   Wikipedia

  • Alexandria — /al ig zan dree euh, zahn /, n. 1. Arabic, Al Iskandarîyah. a seaport in N Egypt, in the Nile delta: founded in 332 B.C. by Alexander the Great; ancient center of learning. 2,201,000. 2. a city in NE Virginia, S of the District of Columbia.… …   Universalium

  • Hero — /hear oh/, n. 1. Class. Myth. a priestess of Aphrodite who drowned herself after her lover Leander drowned while swimming the Hellespont to visit her. 2. Also, Heron. (Hero of Alexandria) fl. 1st century A.D., Greek scientist. * * * I… …   Universalium

  • Hero (disambiguation) — A hero is a person who performs extraordinary deeds for the benefit of others.Hero may also refer to:Heroic figures* Superhero, a hero with extraordinary powers * Hero (title), a title presented by governments to their citizens for great… …   Wikipedia

  • hero — herolike, adj. /hear oh/, n., pl. heroes; for 5 also heros. 1. a man of distinguished courage or ability, admired for his brave deeds and noble qualities. 2. a person who, in the opinion of others, has heroic qualities or has performed a heroic… …   Universalium

  • Hero's formula — /hear ohz/, Geom. the formula for the area of a triangle when the sides are given: for a triangle with sides a, b, and c, the area is equal to sqrt(s(s a)(s b)(s c)), where s is equal to one half the perimeter of the triangle. [named after HERO… …   Universalium

  • Hero — He•ro [[t]ˈhɪər oʊ[/t]] n. 1) myt a legendary priestess of Aphrodite and the lover of Leander 2) big Also, Heron (Hero of Alexandria) fl. 1st century a.d. , Greek scientist …   From formal English to slang

  • Hero's formula — /hear ohz/, Geom. the formula for the area of a triangle when the sides are given: for a triangle with sides a, b, and c, the area is equal to sqrt(s(s a)(s b)(s c)), where s is equal to one half the perimeter of the triangle. [named after HERO… …   Useful english dictionary

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”