Archimedes Born
Archimedes of Syracuse, born around 287 BCE by most scholarly reckoning, is widely regarded as the greatest mathematician and engineer of the ancient world. The date of 264 BCE given for this entry is not the one most historians accept. The usual estimate comes from the twelfth-century Byzantine writer John Tzetzes, who says Archimedes died at about seventy-five, and his death during the Roman capture of Syracuse in 212 BCE points to a birth near 287. Either way, the exact year is uncertain, and no contemporary record of it survives.
He was born in Syracuse, a wealthy Greek city on the east coast of Sicily. The Roman biographer Plutarch connects him to the city's ruler, Hieron II, and an ancient source, usually read as Archimedes himself, names his father as an astronomer called Phidias. He seems to have spent time in Alexandria, then the intellectual center of the Greek world, where he likely became acquainted with scholars in the circle of Euclid's successors. He later returned to Syracuse and worked there for the rest of his life.
His mathematical achievements were remarkable. He worked out the area of a circle and a close estimate of pi by fitting polygons inside and outside it. He found the volume and surface area of the sphere, and was reportedly so proud of the result that he wished it to be shown on his tomb. His method of exhausting a shape with ever-smaller pieces anticipated ideas later central to calculus. In The Sand Reckoner, he devised a way of naming enormous numbers, showing that counting need not be limited by the largest number people could then express.
In physics he laid out the law of the lever and the principles of floating bodies, now known as Archimedes' principle: an object immersed in fluid is buoyed up by a force equal to the weight of the fluid it displaces. The famous story of "Eureka!" comes from the Roman writer Vitruvius, who describes him spotting the principle in a bath while testing whether a goldsmith had cheated Hieron by mixing silver into a crown. The tale was written down two centuries later and may be embellished, and the method it describes is probably not how he actually worked.
Later writers also credit him with war machines used against the Romans, including catapults and grappling devices, though accounts such as a "burning mirror" are doubted by many historians. Archimedes was killed in 212 BCE when Syracuse fell. His works were copied, translated, and studied through the Byzantine, Islamic, and Renaissance worlds, influencing Galileo and others. A tenth-century manuscript of his writings, later overwritten as a prayer book, was recovered in modern times and revealed previously unknown texts.