Archimedes

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Archimedes (287-212 BC) was a Greek inventor, philosopher and brilliant mathematician. His best known theory was that, if given a big enough lever and a place to stand, one could move the earth.

Another popular Archimedes story is when a king thought he was being cheated out of his money, as he thought his crown was not pure gold. Archimedes used a theory about water displacement caused by weight to figure out that the crown in question did have silver, when the king paid for pure gold. After figuring this out in the bathtub, Archimedes ran through the town naked, yelling "Eureka!" (I have found it!). Archimedes is also well known for inventing the field of statistics, and an irrigation device called the Archimedes Screw.

Archimedes (Greek: Αρχιμηδηc) is best known as a Greek engineer who lived in the third century BC. In addition to being an engineer, he was a physicist, astronomer, mathematician, and philosopher. Few facts are known about Archimedes’ actual life besides his discoveries, inventions, and writings, but he was probably born around 287 BC in Syracuse. His father was Phidias, an astronomer, and he was probably also related to Hieron II, a king of Syracuse. Syracuse was a rich fortified city and seaport near Sicily. When Archimedes was around ten years old, he left Syracuse to study in Alexandria, Egypt under the successors of Euclid. It is not known whether he married and had children or not. Archimedes became very famous because of the Punic Wars. He defended Syracuse against Roman sieges in both wars with war machines that he had designed. One of the most amazing was the claw of Archimedes, also called the iron hand. It was used to defend the seaward side of the city wall against attacks from ships. Although it is unclear exactly how it was used, most ancient historians write that it was a kind of crane attached to a hook that lifted ships out of the water and then either dropped them back down or caused them to capsize. Once, when a fleet of 220 Roman warships entered the harbor, the claws of Archimedes were used and many of the ships were sunk before they had a chance to attack. Livy and Polybius attribute their victory to the machines. Archimedes also created something called the ship-shaker. The ship-shaker enabled one man to pull an entire ship, complete with sails, crew, and cargo, on one rope. It was used to ward off invasions by Roman ships. Historians differ on how it was used, but one interesting way was to attach two ship-shakers to one ship and then have men on opposite sides of the harbor pull the ship apart. It worked by using a block and tackle pulley, which Archimedes also invented. In addition to those two inventions, he designed improved versions of many war machines, including the ballista and catapult. Syracuse was able to hold the Romans at bay for a long time because of Archimedes. Because Archimedes lived thousands of years ago, someone else may have done many of the things that are normally attributed to him, and some may never have even happened. One famous legend is that Archimedes prevented another Roman attack by using an array of polished shields to reflect the sunlight towards the Roman ships, causing them to catch fire. Many tests have been done to determine if it was possible. They have all proved that it was possible, but that the ships would have had to be very close to shore and almost motionless for them to ignite, and that did not match any of the descriptions of the siege. Archimedes made many other inventions besides those used in the siege of Syracuse. He probably also invented an early odometer. It was built on a chariot with wheels that turned four hundred times in one Roman mile. A pin on a wheel would engage a 400-tooth gear, so it made one revolution per mile. The gear would turn a wheel that was divided into sections, each one holding a pebble. When it turned, a pebble would fall into a bowl or cup at the bottom. Once someone had finished pushing the chariot, he could count the number of pebbles at the bottom to find out how many miles he had gone. Archimedes invented the Archimedean screw, a simple machine used to move water to a higher level for irrigation. It is made of a screw inside of a tube. A man would turn a crank that turned the screw, and water would come out. Writings about the Hanging Gardens of Babylon hint that the Mesopotamians may have used a similar device three hundred years before. Archimedes also invented the block and tackle (compound) pulley, which enabled him to create the ship-shaker. He also helped to make the use of the lever much more common in everyday tasks. Archimedes once said about the lever, “Give me a place to stand and I will move the Earth!” Archimedes discovered many important principles. He discovered buoyancy, water-displacement, and density when asked to determine whether a crown was made of pure gold or silver coated with gold. There is a story that Archimedes was trying to figure it out when he went to a bathhouse. As he got in, he noticed that the water level rose. He realized how to tell what the crown was made of, and he ran through the streets naked yelling, “Eureka!” He discovered that the rise in the water level would be equal to the volume of the crown. Archimedes is the first mathematical physicist on record, and he invented the field of statics. He was also the first to explain the laws of the lever, equilibrium, and fluids. Using only ancient Greek geometry, Archimedes solved problems that would be hard for a modern physicist using calculus. Many say that he must have come very close to discovering calculus, even though Archimedes lived thousands of years before it actually was discovered. There were many famous people alive at the same time as Archimedes. Hiero, or Hieron, was a king of Syracuse. He was probably related to Archimedes and was born twenty years earlier. Hiero signed a treaty with Rome and was their ally. His son was Gelo (Gelon), who co-ruled with him until Gelo was about fifty, when they both died. He was succeeded by Hieronymos in 215 B.C. Hieronymus was fifteen years old. Both Gelo and Hieronymus supported Carthage in the Punic Wars. Also alive when Archimedes was born was Pyrrhos, a king of Epirus and the cousin of Alexander the Great. He was famous for helping the Greeks fight the Romans. Archimedes was about twenty years old when Claudius Marcellus was born. He was one of the main Roman leaders in the Punic Wars. He led the invasion of Syracuse, and one of his soldiers killed Archimedes. The main leader of the Carthaginians was Hannibal, who was alive at the same time as Archimedes. During the Second Punic War, Hannibal led his soldiers and elephants from Spain to Italy. Archimedes died in 212 B.C. A Roman soldier killed him during the Second Punic War in the sack of Syracuse. The soldiers had been ordered to not harm Archimedes, but the soldier told the Roman general, Marcellus, that Archimedes had his back to him so he didn’t know who he was. The soldier was quickly put to death. Some speculate that the soldier actually did know that the man was Archimedes, but he was seeking retribution because of the damage that Archimedes’ war machines had done to the Roman ships. The story is that Archimedes was killed while drawing in the sand. He was so interested in his diagram that he didn’t even notice the Roman soldier behind him. His famous last words were, “Don’t disturb my circles!” Archimedes was a physicist, astronomer, mathematician, and philosopher. He helped the Greeks. Archimedes is generally regarded by most historians as the greatest mathematician and scientist of the ancient world and, along with Isaac Newton and Carl Friedrich Gauss, one of the three greatest mathematicians of all time.