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An Encyclopedia of the History of Technology part 47

An Encyclopedia of the History of Technology part 47. This one of a kind encyclopedia presents the entire field of technology from rudimentary agricultural tools to communication satellites in this first of its kind reference source. Following an introduction that discusses basic tools, devices, and mechanisms, the chapters are grouped into five parts that provide detailed information on materials, power and engineering, transportation, communication and calculation, and technology and society, revealing how different technologies have together evolved to produce enormous changes in the course of history | PART THREE TRANSPORT Figure 8.3 Nicolas Cugnot s steam Traction Engine built in 1769 to draw artillery. antagonism. Trevithick s steam transport experiments were thenceforth confined to rails. In 1804 a locomotive of his design drew a load of some 10 tonnes and 70 men the 15.5km 9.75 miles from Penydaran to Abercynon South Wales in just over four hours. It was Trevithick s use of high pressure steam rather than Watt s self-imposed restriction to atmospheric pressure working that allowed the development of locomotion. BICYCLES The idea of using human muscular effort for the propulsion of light road vehicles seems to originate as early as Roman times but apart from spasmodic experiments was not seriously developed until the late eighteenth and early nineteenth centuries. The hobby-horse or dandy-horse era took off in 1817 when Baron Karl Drais von Sauerbronn of Mannheim demonstrated his Draisine in the Luxembourg Gardens in Paris. It had a wooden frame a steerable front wheel and an armrest behind the handlebars which gave the rider a greater purchase in thrusting his feet against the ground. In spite of the inefficiency of this awkward method of propulsion a journey from Beaune to Dijon a distance of 37km just over 23 miles could be made by Draisine in 2 1 2 hours an average speed of 15kph or nearly 9 1 2mph. The popularity of the vehicle as a fashionable novelty rather than a practical means of transport led to its rapid adoption in other countries as well as France particularly England see Figure 8.5 Germany and the USA. 442 ROADS BRIDGES AND VEHICLES Figure 8.4 Richard Trevithick s steam carriage of 1802. Little public interest was shown and Trevithick turned his attention to rail locomotion. The first man to appreciate the gyroscopic effect of two wheels mounted in line and the possibility that it gave of lifting the feet from off the ground was Kirkpatrick Macmillan a blacksmith of Courthill Dumfriesshire. In 1839 he invented and built the world s first .