A Bicycle
Essay by review • February 26, 2011 • Essay • 458 Words (2 Pages) • 1,508 Views
A bicycle is a vehicle with two wheels that you ride by steering with handlebars and by pedaling. The name of the modern vehicle dates from 1869.
In 1690 a Frenchman invented the celeriferek consisting of a wooden bem to which the wheels were affixed. The vehicle has not handlebar, the rider sat on a cusion on the beam and propelled and steered the machine by pushing his or her feet against the ground. In 1816 a German noblemen designed the first two-wheeled vehicle with a steering device. This machine named the draisine (after the inventor), had a handlebar that pivoted on the frame, enabling the front wheel to be turned. Improvements were later developed by French, German, and British inventors. In England these early models were known as hobbyhourses; the name dandy horse was applied particularly to the expensisve pedestrian curricle, invented in 1818. The curricle was lighter in weight than the draisin and had an adjusted saddle and elbow rest. It was patented in the United States in 1819 but aroused little interest. In 1839 driving levers and pedals were added to a machine of the draisine type by Kirkpatrick macmillan of Scotland. These innovations enabled the rider to propel the machine with the feet off the ground. The diving mechanism consisted of short craks fixed to the rear wheel hub and connected by rods were joined to the levers at about one third of the foot. In 1846 an approved model of this machine, designed by a Scotsman, acquired the name dalzell and was widely used in England.
The modifications and improvements of the next 15 years included the ball bearing and the pneumatic tire. These inventions along with the use of the weldless steel tubing and spring seats brought the ordinary bicycle to its highest point of development. The excessive vibrationand instability of the high-wheel bicycle, however, caused inventors to turn their attentions to reducing the height of the bicycle. About 1880 the so-called safety, or low, mcahine was developed. The hweels were of nearly equal size, and the pedals attached to sprocket through gears and chain drove the rear wheel Manufacuters in the U.S. universally adopted the safety bicycle. The improved safety machine had wheels of equal size, hollow steel tubing, coaster brakes, adjustable handlebars, and other improvements. American cyclists invreased greatly in numbers and became strong supporters of a nationwide movement
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