# 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 that was lost until 1896. This book also describes a method for finding the square root of a number, a method now used in computers, but known to the Babylonians in 2000 bc. In another of Hero's books,*Pneumatica*(Pneumatics), he wrote on siphons, a coin-operated machine, and the aeolipile – a prototype steam-powered engine that he had built. The engine consisted of a globe with two nozzles positioned so that steam jets from the inside made it turn on its axis. Hero also wrote on land-surveying and he designed war engines based on the ideas of Ctesibius. Yet another of his works,*Mechanica*(Mechanics), was quoted by Pappus of Alexandria.

*Scientists.
Academic.
2011.*

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**Hero of Alexandria**— Heron Born c. 10 AD Residence … Wikipedia**Hero of Alexandria**— SUBJECT AREA: Architecture and building, Mechanical, pneumatic and hydraulic engineering, Photography, film and optics, Steam and internal combustion engines [br] fl. c.62 AD Alexandria [br] Alexandrian mathematician and mechanician. [br] Nothing … Biographical history of technology**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**Alexandria, Hero of**— See: Hero of Alexandria … Biographical history of technology**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