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| tincupnecklaces.com | History of technology | Prehistoric times | Ancient Egypt, Papyrus | Tribal Europe, Germanic tribes | Ancient Greece, Alexandria and Archimedes | Ancient Roman technology | Ancient India |
Ancient Greece, Alexandria and Archimedes
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Hero of Alexandria invented a steam engine and documented the use of
many mechanic, pneumatic and other devices. Archimedes invented
several machines. Hero (or Heron) of Alexandria (c. 10 – 70) was a Hellenized Egyptian engineer and geometer in Alexandria, Egypt. His most famous invention was the first documented steam engine, the aeolipile. He is said to have been a follower of the Atomists. Some of his ideas were derived from the works of Ctesibius. A number of references mention dates around 150 BC, but these are inconsistent with the dates of his publications and inventions. This may be due to a misinterpretation of the phrase "first century" or a confusion of this Hero with other Heroes- Hero was not an uncommon name. It is also believed that Heron taught at the Museum in Alexandria. This is because most of his writings appear as lecture notes for courses, based in mathematics, mechanics, physics, and pneumatics as well as his publications which appear as textbooks. |
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Archimedes (Greek: Αρχιμήδης ) (c. 287 BC–212 BC) was an ancient
Greek mathematician, physicist, engineer, astronomer and philosopher
born in the seaport colony of Syracuse, Sicily. He is considered by
some historians of mathematics to be one of the greatest
mathematicians in antiquity; Carl Friedrich Gauss considered him one
of the two greatest ever. Archimedes became a popular figure as a result of his involvement in the defense of Syracuse against the Roman siege in the Second Punic War. He is reputed to have held the Romans at bay with war machines of his own design; to have been able to move a full-size ship complete with crew and cargo by pulling a single rope[1]; to have discovered the principles of density and buoyancy, also known as Archimedes' principle, while taking a bath (thereupon taking to the streets naked he called "Eureka"). He has also been credited with the possible invention of the odometer during the First Punic War. One of his inventions used for military defense of Syracuse against the invading Romans was the claw of Archimedes. It is said that he prevented one Roman attack on Syracuse by using a large array of mirrors (speculated to have been highly polished shields) to reflect sunlight onto the attacking ships causing them to catch fire. This popular legend was tested on Discovery Channel's Myth Busters program. After a number of experiments, whereby the hosts of the program tried burning a model wooden ship with a variety of mirrors, they concluded that the enemy ships would have had to have been virtually motionless and very close to shore for them to ignite, an unlikely scenario during a battle. A group at MIT subsequently performed their own tests and concluded that the mirror weapon was a possibility , although later tests of their system showed it to be ineffective in conditions that more closely matched the described siege . It is also said that Archimedes invented the catapult to hurdle boulders at attacking ships. While at first seeming plausible because he did invent several types of pulley systems, the catapult is recorded as actually having been used by Dionysius 1 of Syracuse approximately one hundred years earlier. Archimedes was killed by a Roman soldier in the sack of Syracuse during the Second Punic War, despite orders from the Roman general, Marcellus, that he was not to be harmed. The Greeks said that he was killed while drawing an equation in the sand; engrossed in his diagram and impatient with being interrupted, he is said to have muttered his famous last words before being slain by an enraged Roman soldier: Μη μου τους κύκλους τάραττε ("Don't disturb my circles"). This story was sometimes told to contrast the Greek high-mindedness with Roman ham-handedness; however, it should be noted that Archimedes designed the siege engines that devastated a substantial Roman invasion force, so his death may have been out of retribution. In creativity and insight, he exceeded any other European mathematician prior to the European Renaissance. In a civilization with an awkward numeral system and a language in which "a myriad" (literally "ten thousand") meant "infinity", he invented a positional numeral system and used it to write numbers up to 1064. He devised a heuristic method based on statistics to do private calculation that we would classify today as integral calculus, but then presented rigorous geometric proofs for his results. To what extent he actually had a correct version of integral calculus is debatable. He proved that the ratio of a circle's perimeter to its diameter is the same as the ratio of the circle's area to the square of the radius. He did not call this ratio π but he gave a procedure to approximate it to arbitrary accuracy and gave an approximation of it as between 3 + 10/71 (approximately 3.1408) and 3 + 1/7 (approximately 3.1429). He was the first Greek mathematician to introduce mechanical curves (those traced by a moving point) as legitimate objects of study. He proved that the area enclosed by a parabola and a straight line is 4/3 the area of a triangle with equal base and height. (The "base" is any secant line, not necessarily orthogonal to the parabola's axis; "the same base" means the same "horizontal" component of the length of the base; "horizontal" means orthogonal to the axis. "Height" means the length of the segment parallel to the axis from the vertex to the base. The vertex must be so placed that the two horizontal distances mentioned in the illustration are equal.) |
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| tincupnecklaces.com | History of technology | Prehistoric times | Ancient Egypt, Papyrus | Tribal Europe, Germanic tribes | Ancient Greece, Alexandria and Archimedes | Ancient Roman technology | Ancient India |