The crossbow was not invented as an instrument of war, but as a peacemaking device. It was invented to calm the fighting between states at the end of the Zhou dynasty. The idea was that if someone appeared with a more advanced and more powerful weapon, everyone else would stop fighting and obey the people with the crossbow. The crossbow was considered so advanced that around 200 BC, a law was passed to prevent people from taking crossbows out of China, for fear that enemies would replicate them. Crossbows and trigger mechanisms were mass-produced so
heavily that, in about 157 BC, a prince named Liang Hsiao Wang was in charge of regiments that had 50,000 men and several hundred thousand crossbows. Some crossbows were so big that they needed several men to ready them for firing. And, in the eleventh century, rapid-firing crossbows were developed that could fire 20 arrows in only 15 seconds. The Chinese used the crossbow in battle as late as 1895. By then, of course, modem firearms had outdated it.
The crossbow is used today as a hunting weapon, and for target practice at archery ranges. Modem crossbows have many metal parts, and are vary lightweight. A slightly modified version of the Chinese crossbow's trigger mechanism is used in modern handguns. The Ancient Chinese invented many things, but I think one of the most important of all is the crossbow.
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