Energy
Although the origin of candles is obscure, they are mentioned by Philon [b. Byzantium (Turkey), c. 280 bce, d. c. 220 bce] about this time. Some think candles were invented by the Etruscans. Tapers (wicks dipped in wax once) and wax-impregnated reeds preceded candles, but the earliest form of artificial lighting device was the oil lamp. Even at this time, and for the next 2000 years, lamps are preferred to candles as light sources. See also 598 bce Energy; 60 ce Energy.
MaterialsAccording to tradition, parchment is invented about this time in Pergamum (Bergama, Turkey), from which its name is derived. Parchment is animal skin treated so that it can be written on both sides. Vellum, which may have originated later, is often taken to be parchment made from very young or unborn animals. See also 2500 bce Materials; 250 ce Materials.
Philon of Byzantium advocates the use of bronze springs in catapults and experiments with the expansion of air by heat.
MathematicsArchimedes shows that numbers can be written as large as needed, calculates a close value for π, and develops improved methods of finding areas and volumes enclosed by curves or curved surfaces. See also 430 bce Mathematics.
ToolsArchimedes works out the principle of the lever and other simple machines. He demonstrates this by launching a large ship by himself. He may have invented the compound pulley and used this in his demonstration. He invents the Archimedean screw, still used to lift water from rivers. See also 390 bce Tools; 880 Physics. (See essay.)
Philon of Byzantium builds a cardan joint, a form of universal joint using two interlocked forks, although traditionally this device has been attributed Girolamo Cardano. Philon also describes a primitive form of the chain-and-sprocket drive (now used in bicycles) and an early application of an undershot water wheel to power a bucket-and-chain water hoist. Shortly after this time other evidence suggests that water wheels were employed in grinding grain, although the connection between these and Philon's work, if any, has been lost. Philon also designs a chain drive for use in repeat loading of a catapult. In his book On the Lifting of Heavy Weights he describes a system of gears. See also 25 bce Energy.
