Heron of Alexandria

from Wikipedia, the free encyclopedia
Fantasy representation of Heron in a German edition of the Pneumatika from 1688

Heron of Alexandria ( Greek  Ἥρων Hḗrōn , called Mechanicus (ὁ μηχανικός); † after 62 ) was a Greek mathematician and engineer. He taught at the Museion of Alexandria , whose library was famous.

Works

Herons Ball
Heron's wind-powered organ (reconstruction)

Heron's works have only survived in fragments; Apparently some of these are lecture notes, and of the mathematical writings handed down under his name, only Definitions and Metrica can be directly traced back to him, the others are, according to JL Heiberg, rather Byzantine school books, of which it is difficult to say anything by Heron originates and what is not. The technical works, on the other hand, apart from Cheirobalistra, are written by Heron. The following works have been preserved under his name: Dioptra ("Book of Optics "); Automata ("Book of Machines"); Pneumatika ("Book of Pneumatics and Hydraulics "); Belopoeika ("Book of Projectiles "); Metrika ("Book of Measurement"), Catoptrica , Barulkos (a treatise in Mechanics and Dioptrics by Heron devoted to the lifting of a large weight by a single man, but the method was not used in ancient times), Cheirobalistra , Definition , Geometricca , De mensuris , Stereometrica . Among other things, they deal with mathematical, optical and mechanical topics. Above all, his statements on automatic, sometimes even programmable devices and the use of water, air and heat as the driving force are known. The invention of the aeolipil , also called Heronsball, and the Heronsbrunnen should be mentioned here in particular .

Earlier, when his mechanics and metrics were not yet known, Heron was seen as a pure technician without much theoretical background, mainly because of his major work Pneumatika, according to von Heiberg, and Hermann Diels called him a pure peasant . That changed after mechanics was discovered in an Arabic manuscript (published in German in 1900 and in French in 1893), which also included a theoretical part and was much more structured than pneumatics, and a manuscript of metrics in its original form showed that mathematically he was up to date. His dioptric also showed that he knew a lot about astronomy. In the theoretical part, mechanics largely follows Archimedes', for example in the theory of the focal points.

In addition, the Heron method for calculating the square root and the Heron theorem are known, which allows the area of a triangle to be calculated only with knowledge of the length of the three sides, without knowing the angles or other parts of the triangle. In the treatise Metrika , the scholar provides evidence of Heron's formula, which was later named after him . The name Heronian triangle is also reminiscent of the ancient mathematician.

Fantasy portrait of Heron of Alexandria on an engraving from 1688

In the dioptra he describes devices for field measurement . The dioptra itself is an instrument that fulfilled the function of today's theodolite . Like Archimedes, he uses an odometer for longer distances on the road . He criticizes the groma . For distances across seas, he recommends astronomical methods such as observing lunar eclipses . The catoptric was previously ascribed to Ptolemy and is only preserved in Latin. It's about mirrors.

In his work Automata , he explains how his designs are made and used. For example, temple doors are described as automaton no. 37, which were supposed to open automatically when a fire was lit on an altar. In addition to music machines, he even developed automatic theaters with special effects that were sensational for the time.

His inventions also include the construction of a holy water machine, described in his work Pneumatika , which is considered to be the oldest vending machine in the world. A wooden disc lay on the surface of the holy water. As soon as a coin was inserted, its weight pushed the consecrated water up through a metal tube that the believer could receive. In addition to many playful devices, a water organ and a fire pump are also described. The Pneumatika are his most extensive work, but it is not fully worked out, rather it consists partly only of notes. In the introduction the vacuum is treated - with the teaching of the horror vacui - and air and water pressure. It was Heron's most widely read work in the Middle Ages and early modern times, with over 100 preserved manuscripts.

With the Aeolipile (Heronsball) , Heron designed the first known and documented heat engine in history. However, it was not understood and used as such, but was considered a curiosity. It was not until around a millennium and a half later that steam engines were used to perform work in France and England .

Heron also devoted himself to the development of weapons technology in Belopoeika , including describing the gastraphetes and catapults. The design of a catapult for several arrows in Cheirobalistra can be considered the forerunner of the machine gun. However, the attribution of this work to Heron is not certain. Cheirobalista is only contained in fragments and is probably part of a lexicon on catapults.

On the dating ("Heronian question")

Heron's life dates are not yet known for certain. According to the sources, he must have lived after Archimedes (whom Heron quotes) but before Pappos, who quotes from Heron's mechanics, i.e. H. vaguely between 200 BC And 300 AD A more precise classification by Otto Neugebauer showed in 1938 that Heron probably lived in the 1st century AD. Because in his work Dioptra a lunar eclipse is mentioned, which was seen ten days before the spring equinox . His statement that it occurred in Alexandria in the 5th (night) hour leads to the time frame 200 BC. BC to AD 300 clearly related to the lunar eclipse of March 13, 62 (Julian).

Nathan Sidoli and others have recently questioned this dating of Neugebauer. Neugebauer would have been too imprecise with the information given by Heron, so other lunar eclipses could also be used for dating. It seems, however, that Sidoli calculated once according to the Gregorian and then according to the Julian calendar when calculating the spring equinox and the lunar eclipse. Thus the dating of Neugebauer would remain in force.

Illustrations in manuscripts

  • Heron of Alexandria, Automata 13: Sketch of an automaton, a Bacchus figure dispensing wine and milk in a little temple. The figure is connected by invisible tubes with hidden wine and milk containers, which allow wine and milk to flow into the Thyrsos wand through the opening of valves . The drawing shows the vascular chambers, lines and valves. Venice, Biblioteca Nazionale Marciana , Gr. 516, fol. 202r (early 14th century)

  • Heron of Alexandria, Pneumatica 1,16: Technical drawing of a hydraulic apparatus of the singing artificial birds in the manuscript Venice, Biblioteca Nazionale Marciana, Gr. 516, fol. 172v (early 14th century)

  • Heron of Alexandria, Belopoiika 5: Construction drawing of a smaller gun in the Paris manuscript, Bibliothèque Nationale , Suppl. Graec. 607, fol. 47v (11th century)

  • Heron of Alexandria, Belopoiika 23: Construction drawing of a large gun in the manuscript Paris, Bibliothèque Nationale, Graec. 2442, fol. 76v (11th / 12th century)

reception

By Heron of Alexandria the moon crater Heron named.

Fonts

  • Heronis Alexandrini Opera quae supersunt omnia, Teubner, Greek / German, 5 volumes, 1899–1914 (contains all writings except Belopoiica)
    • Volume 1 Pneumatica et automata, 1899 ( online ), Volume 2 Mechanica et Catoptrica, 1900, Volume 3 Rationes dimetiendi et comentatio dioptrica 1903, Volume 4 Heronis definitiones cum variis collectionibus 1912, Volume 5 Heronis quae feruntur stereometrica et de mensuris 1914
  • Heron's Belopoiica Greek and German, Eds. H. Diels, E. Schramm, Abh. Preuss. Akad. Wiss., Phil.-Hist. Class, No. 2, 1918

literature

  • AG Drachmann: Hero of Alexandria . In: Charles Coulston Gillispie (Ed.): Dictionary of Scientific Biography . tape 6 : Jean Hachette - Joseph Hyrtl . Charles Scribner's Sons, New York 1972, p. 310-314 and 314-315 .
  • Giovanna R. Giardina: Héron d'Alexandrie. In: Richard Goulet (ed.): Dictionnaire des philosophes antiques. Volume supplément. CNRS Editions, Paris 2003, ISBN 2-271-06175-X , pp. 87-103 (overview of the state of research).
  • Hans Michael Schellenberg: Notes on Heron of Alexandria and his work on gun construction. In: Hans Michael Schellenberg u. a. (Ed.): A Roman Miscellany. Essays in Honor of Anthony R. Birley on his Seventieth Birthday. Gdańsk 2008, pp. 92–130 (with extensive bibliography and information on the state of research).
  • Technical Museum of Thessaloniki, Study Society for Ancient Greek Technology (ed.): Ancient Greek Technology: An Approach with Replicated Constructions from the Amazing Work of the Ancient Greek Masters . Thessaloniki 2000, ISBN 960-7619-10-2 .
  • Helge Svenshon: Heron of Alexandria and the Dome of Hagia Sophia in Istanbul (PDF). In: Karl-Eugen Kurrer , Werner Lorenz , Volker Wetzk (eds.): Proceedings of the Third International Congress on Construction History . Neunplus, Berlin 2009, ISBN 978-3-936033-31-1 , pp. 1387-1394.
  • Helge Svenshon: The building as "aistheton soma" - a reinterpretation of Hagia Sophia in the mirror of ancient surveying and applied mathematics. In: Falko Daim, Jörg Drauschke (Hrsg.): Byzanz - The Roman Empire in the Middle Ages. RGZM monographs, 84 (2.1). Mainz 2010, ISBN 978-3-88467-154-2 , pp. 59–95 (investigation into Heron's surveying and vaulting theory as the basis for planning the Hagia Sophia in Constantinople).
  • Manuela Rausch: Heron of Alexandria: The automat theater and the invention of the first ancient program control. Diplomica, Hamburg 2012, ISBN 978-3-8428-8632-2 ( excerpt from google books ).

Web links

Commons : Heron of Alexandria  - Collection of images, videos and audio files

Remarks

  1. ↑ Drachmann, Dict. Sci. Biogr., Volume 6, p. 311
  2. ↑ Drachmann, Dict. Sci. Biogr., Volume 6, p. 310
  3. ↑ After Drachmann, Dict. Sci. Biogr., Volume 6, p. 313, it is attributed to Heron
  4. ^ The Pneumatics of Hero of Alexandria
  5. ^ First published by Rudolf Schneider, Mitt. Kaiserlich Deutsches Archäologisches Institut, Römische Abt., Volume 21, 1906, pp. 142ff, and in English translation by EW Marsden, Greek and Roman Artillery. Technical Treatises, Oxford 1971, with reconstruction of the catapult
  6. ↑ Franz Krojer: Heronsgezänk. In: Astronomie der Spätantike, die Null and Aryabhata , Munich 2009, p. 31 ff. ( PDF ). See Nathan Sidoli: Heron of Alexandria's Date. In: Centaurus 53/1, 2011 ( PDF ).
personal data
SURNAME Heron of Alexandria
ALTERNATIVE NAMES Ἥρων ὁ Ἀλεξανδρεύς (Heron ho Alexandreús)
BRIEF DESCRIPTION ancient mathematician and engineer
DATE OF BIRTH uncertain: 1st century
DATE OF DEATH after 62