A bicycle is two-wheeled vehicle propelled by its rider. The most energy-efficient means of transportation, the bicycle is used through out the world. Particularly in developing countries-most notably in China, where some 154 million bicycles are on the road. The vehicle has been a common form of local transportation for many years.
The first step toward the development of the bicycle was the invention of the celerifere or wooden horse, probably in France in the 1790s. Because its front wheel was fixed, this vehicle could not be steered, and the rider propelled it by pushing his or her feet along the ground. An important advance was made by the German baron Karl von Drais in 1817, when he introduced a steerable front wheel, creating the draisienne, or dandy horse. In 1838, Kirkpatrick Macmillan, a Scottish blacksmith, made the first machine with pedals, which were attached to and drove the rear wheel by means of cranks. On the velocipede, a French invention of 1852, the front wheel was pedal driven and revolved once with each revolution of the pedals. The speed of the machine was dependent on the size of the front wheel. The larger the wheel, the faster the bicycle. The front wheel of the high-wheel, or pennyfarthing-used from 1870s-reached diameters of 1.5 m and more, while the back wheel might be only one-quarter that size. With its seat mounted over the huge front wheel, the high-wheel was dangerously unstable, and its use on poor roads led to many bicycling accidents.
An English "safety bicycle", with a chain and sprocket driving the rear wheel, was introduced by H.J Lawson in 1887. In 1885 a safety designed by J.K. Starley, which had wheels of equal size, became the basic model for the modern bicycle.
Photos by : Goenadi Haryanto
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