Wednesday, November 24, 2010

Napoli Computers

# Wright, M T., "Il meccanismo di Anticitera: l'antica tradizione dei meccanismi ad ingranaggio" (The Antikythera Mechanism: evidence for an ancient tradition of the making of geared instruments), in: E. Lo Sardo (ed.), Eureka! Il genio degli antichi, Naples, July 2005 – January 2006), Electa Napoli 2005, pp. 241 – 244.
# ^ Wright, M T. (2004). "Il meccanismo di Anticitera: l'antica tradizione dei meccanismi ad ingranaggio (The Antikythera Mechanism: evidence for an ancient tradition of the making of geared instruments)". Αρχαιολογία & Τέχνες 95 (June 2005): 54–60.
# ^ Wright, M T. (2005). "Ο Μηχανισμός των Αντικυθήρων (The Antikythera Mechanism)". Αρχαιολογία & Τέχνες 95 (June 2005): 54–60.



source:http://en.wikipedia.org

Planetarium Computers

# a b Wright, M T. (July 2002). "In the Steps of the Master Mechanic". Proc. Conf. Η Αρχαία Ελλάδα και ο Σύγχρονος Κόσμος (Ancient Greece and the Modern World). Ancient Olympiai. pp. 86–97. University of Patras 2003.
# ^ Wright, M T. (2002). "A Planetarium Display for the Antikythera Mechanism (a)". Horological Journal 144 (5 (May 2002)): 169–173.
# ^ Wright, M T. (2002). "A Planetarium Display for the Antikythera Mechanism (b)". Horological Journal 144 (6 (June 2002)): 193.
# ^ a b Wright, M T. (2005). "The Antikythera Mechanism and the early history of the Moon Phase Display". Antiquarian Horology 29 (3 (March 2006)): 319 – 329.

Mathematical Computers

Wright, M T.; Bromley, A. G., & Magkou, E (1995). "Simple X-ray Tomography and the Antikythera Mechanism". PACT (Revue du groupe européen d'études pour les techniques physiques, chimiques, biologiques et mathématiques appliquées à l'archéologie or Journal of the European Study Group on Physical, Chemical, Biological and Mathematical Techniques Applied to Archaeology) 45: 531–543.

HISPANIA COMPUTERS

On 30 November 2006, the science journal Nature published a new reconstruction of the mechanism by the Antikythera Mechanism Research Project, based on the high resolution X-ray tomography described above.[49] This work doubled the amount of readable text, corrected prior transcriptions, and provided a new translation. The inscriptions led to a dating of the mechanism to around 100 BC. It is evident that they contain a manual with an astronomical, mechanical and geographical section. The name HISPANIA (ΙΣΠΑΝΙΑ, Spain in Greek) in these texts is the oldest reference to the Iberian Peninsula under this form, as opposed to Iberia.

The new discoveries confirm that the mechanism is an astronomical analog calculator or orrery used to predict the positions of celestial bodies. This work proposes that the mechanism possessed 37 gears, of which 30 survive, and was used for prediction of the position of the Sun and the Moon. Based on the inscriptions, which mention the stationary points of the planets, the authors speculate that planetary motions may also have been indicated.

London Computers

Michael Wright, formerly Curator of Mechanical Engineering at The London Science Museum and now of Imperial College, London, made a completely new study of the original fragments together with Allan George Bromley. They used a technique called linear X-ray tomography which was suggested by retired consultant radiologist, Alan Partridge. For this, Wright designed and made an apparatus for linear tomography, allowing the generation of sectional 2D radiographic images.[29] Early results of this survey were presented in 1997, which showed that Price's reconstruction was fundamentally flawed.[30]

Further study of the new imagery allowed Wright to advance a number of proposals. Firstly he developed the idea, suggested by Price in "Gears from the Greeks", that the mechanism could have served as a planetarium. Wright's planetarium not only modelled the motion of the Sun and Moon, but also the Inferior Planets (Mercury and Venus), and the Superior Planets (Mars, Jupiter and Saturn).[31][32]

Wright proposed that the Sun and Moon could have moved in accordance with the theories of Hipparchus and the five known planets moved according to the simple epicyclic theory suggested by the theorem of Apollonios. In order to prove that this was possible using the level of technology apparent in the mechanism, Wright produced a working model of such a planetarium.[33][34]

Clock Computers

Following decades of work cleaning the device, in 1951 British science historian Derek J. de Solla Price undertook systematic investigation of the mechanism.

Price published several papers on "Clockwork before the Clock".[24][25] and "On the Origin of Clockwork",[26] before the first major publication in June 1959 on the mechanism: "An Ancient Greek Computer".[27] This was the lead article in Scientific American and appears to have been initially published at the prompting of Arthur C. Clarke, according to the book Arthur C. Clarke's Mysterious World (see end of chapter 3). In "An Ancient Greek Computer" Price advanced the theory that the Antikythera mechanism was a device for calculating the motions of stars and planets, which would make the device the first known analog computer. Until that time, the Antikythera mechanism's function was largely unknown, though it had been correctly identified as an astronomical device, perhaps being an astrolabe.

Roman Computers

a 1st century BC philosophical dialogue, mentions two machines that some modern authors consider as some kind of planetarium or orrery, predicting the movements of the Sun, the Moon, and the five planets known at that time. They were both built by Archimedes and brought to Rome by the Roman general Marcus Claudius Marcellus after the death of Archimedes at the siege of Syracuse in 212 BC. Marcellus had a high respect for Archimedes and one of these machines was the only item he kept from the siege (the second was offered to the temple of Virtus). The device was kept as a family heirloom, and Cicero has Philus (one of the participants in a conversation that Cicero imagined had taken place in a villa belonging to Scipio Aemilianus in the year 129 BC) saying that Caius Sulpicius Gallus (consul with Marcellus' nephew in 166 BC, and credited by Pliny the Elder as the first Roman to have written a book explaining solar and lunar eclipses) gave a 'learned explanation' of it and demonstrated it working.

source:http://en.wikipedia.org/

Athens Computers

1. The device is rather small, indicating that the designer was aiming for compactness and, as a result, the size of the front and back dials is unsuitable for public display. A simple comparison with size of the Tower of the Winds in Athens could give us a hint to suggest that the aim of the Antikythera mechanism manufacturer was the mobility of this device rather than its public display in a fixed place (such as a temple, museum or public hall).
2. The mechanism had door plates attached to it that contain at least 2,000 characters, forming what members of the Antikythera mechanism research project often refer to as an instruction manual for the mechanism. The neat attachment of this manual to the mechanism itself implies ease of transport and personal use.
3. The existence of this "instruction manual" implies that the device was constructed by an expert scientist and mechanic in order to be used by a non-expert traveler (the text gives a lot of information associated with well known geographical locations of the Mediterranean area).[citation needed]


source:http://en.wikipedia.org

Egypt Computers

The device is remarkable for the level of miniaturization and for the complexity of its parts, which is comparable to that of 17th century clocks. It has over 30 gears, although Michael Wright (see below) has suggested as many as 72 gears, with teeth formed through equilateral triangles. When a date was entered via a crank (now lost), the mechanism calculated the position of the Sun, Moon, or other astronomical information such as the location of other planets. Since the purpose was to position astronomical bodies with respect to the celestial sphere, with reference to the observer's position on the surface of the Earth, the device was based on the geocentric model.[11]

The mechanism has three main dials, one on the front, and two on the back. The front dial has two concentric scales. The outer ring is marked off with the days of the 365-day Egyptian calendar, or the Sothic year, based on the Sothic cycle. Inside this, there is a second dial marked with the Greek signs of the Zodiac and divided into degrees. The calendar dial can be moved to compensate for the effect of the extra quarter day in the solar year (there are 365.2422 days per year) by turning the scale backwards one day every four years. Note that the Julian calendar, the first calendar of the region to contain leap years, was not introduced until about 46 BC, up to a century after the device was said to have been built


source:http://en.wikipedia.org

Greek Computers

The mechanism is the oldest known complex scientific calculator. It contains many gears, and is sometimes called the first known analog computer,[8] although its flawless manufacturing suggests that it may have had a number of predecessors during the Hellenistic Period which have not yet been discovered.[9] It appears to be constructed upon theories of astronomy and mathematics developed by Greek astronomers and it is estimated that it was made around 150-100 BC. One hypothesis is that the device was constructed at an academy founded by the ancient Stoic philosopher Posidonius on the Greek island of Rhodes, which at the time was known as a center of astronomy and mechanical engineering, and that perhaps the astronomer Hipparchus was the engineer who designed it since it contains a lunar mechanism which uses Hipparchus's theory for the motion of the Moon.

Investigators have suggested that the ship could have been carrying it to Rome, together with other treasure looted from the island to support a triumphal parade being staged by Julius Caesar.[10] However, the most recent findings of The Antikythera Mechanism Research Project, as published in the July 30, 2008, edition of Nature also suggest that the concept for the mechanism originated in the colonies of Corinth, which might imply a connection with Archimedes. The circumstances under which it came to be on the cargo ship are unknown. Consensus among scholars is that the mechanism itself was made in the Greek speaking world.[7] All the instructions of the mechanism are written in Greek.


source:http://en.wikipedia.org

Tuesday, November 23, 2010

Europe Computers

The Antikythera mechanism (pronounced /ˌæntɨkɨˈθɪərə/ ANT-i-ki-THEER-ə or pronounced /ˌæntɨˈkɪθərə/ ANT-i-KITH-ə-rə), is an ancient mechanical computer[1][2] designed to calculate astronomical positions. It was recovered in 1900–01 from the Antikythera wreck,[3] but its complexity and significance were not understood until decades later. It is now thought to have been built about 150–100 BCE. The degree of mechanical sophistication is comparable to late medieval Swiss watchmaking.[citation needed] Technological artifacts of similar complexity and workmanship did not reappear until the 14th century, when mechanical astronomical clocks appeared in Europe.[4]

Jacques-Yves Cousteau visited the wreck for the last time in 1978,[5] but found no more remains of the Antikythera Mechanism. Professor Michael Edmunds of Cardiff University who led the most recent study of the mechanism said: "This device is just extraordinary, the only thing of its kind. The design is beautiful, the astronomy is exactly right. The way the mechanics are designed just makes your jaw drop. Whoever has done this has done it extremely carefully...in terms of historic and scarcity value, I have to regard this mechanism as being more valuable than the Mona Lisa."[6][7]

The device is displayed in the Bronze Collection of the National Archaeological Museum of Athens, accompanied by a reconstruction made and donated to the museum by Derek de Solla Price. Other reconstructions are on display at the American Computer Museum in Bozeman, Montana, the Children's Museum of Manhattan in New York, and in Kassel, Germany.


source:http://en.wikipedia.org