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The word meaning "chain" can be traced back to an ancient word in the Indo-European language family. As early as 225 BC, chain was used to draw a bucket of water up from a well. This very early bucket chain was composed of connected metal rings.In the 16th century, Leonardo da Vinci made sketches of what appears to be the first steel chain. These chains were probably designed to transmit pulling, not wrapping, power because they consist only of plates and pins and have metal fittings. However, da Vinci's sketch does show a roller bearing.It took some time for the technology to catch up with the concept. Problems in the manufacturing and processing of steel prevented chain growth until the 19th century, when new technologies made steel chain and bearings realities. In the 1800s, a Frenchman named Gull obtained a patent for a similar chain for use on a bicycle. This chain, called "Gull Chain," is still used today in hanging applications.When molded chain was invented in the 19th century, things began to move rather quickly. First came the cast detachable chain, which is composed of identical cast links. Next, the pintle chain, which has a separate pin, appeared. The cast detachable chain and the pintle chain have been improved over the years, and they are still in use today in some special applications.They are being replaced—gradually—by large pitch steel conveyor chain.In the late 1800s, a new development—the bushing—revolutionized steel chain. Chains with bushings had greater wear resistance than Gull Chain because the bushing acted as a bearing, protecting the pin. At this point, the chain story moves into superspeed. Steel bushing chain was used on bicycles, in the rear-wheel drive of early automobiles, and, in 1903, as the propeller drive in the Wright brothers' airplane.