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Today, bicycles are elegantly simple machines that are common around the world. Many people ride bicycles for recreation, whereas others use them as a means of transportation. The first bicycle was invented in Germany in 1818. Because it was made of wood, it wasn’t very strong nor did it have pedals (脚踏板).Riders moved it by pushing their feet against the ground.
In 1839, Kirkpatrick Macmillan, a Scottish blacksmith, invented a much better bicycle. Macmillan’s machine had iron-covered wheels to keep them from getting worn down. He also used foot-operated levers, similar to pedals, so his bicycle could be ridden at a quick pace. It didn’t look much like the modem bicycle, though, because its back wheel was substantially larger than its front wheel. Although Macmillan’s bicycles could be ridden easily, they were never produced in large numbers.
In 1861, Frenchman Pierre Michaux and his brother Ernest invented a bicycle with an improved pedal mechanism. They called their bicycle a velocipede,but most people called it a “bone shaker” because of the effect of the wood and iron frame. Despite the impolite nickname, the velocipede was a hit. After a few years, the Michaux family was making hundreds of the machines annually, mostly for fun-seeking young people.
Ten years later, James Starley , an English inventor, made several innovations that revolutionized bicycle design. He made the front wheel many times larger than the back wheel, put a gear on the pedals to make the bicycle more efficient,and lightened the wheels by using wire spokes. Although this bicycle was much lighter and less tiring to ride, it was still clumsy, extremely top-heavy,and ridden mostly for entertainment.
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