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قراءة كتاب Automobile Biographies An Account of the Lives and the Work of Those Who Have Been Identified with the Invention and Development of Self-Propelled Vehicles on the Common Roads
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Automobile Biographies An Account of the Lives and the Work of Those Who Have Been Identified with the Invention and Development of Self-Propelled Vehicles on the Common Roads
and restoring the first piston to its original position. In order to run the vehicle backwards, the pawl was made to act on the upper side, changing the position of the spring which pressed upon it; then, when the engine was started, the pawl caused the driving-wheel to turn a quarter of a revolution in the opposite direction with every stroke of the piston.
This machine was first tried in 1770 in the presence of a distinguished assembly, that included the Duc de Choiseul; General Gribeauval, First Inspector-General of Artillery; the Compte de Saxe, and others. Subsequently, other trials of it were made, with satisfactory results generally. The heavy over-balancing weight of the engine and boiler in front rendered it difficult to control. On one of its trips it ran into a wall in turning a corner and was partly wrecked. Further experiments with it were abandoned, and in 1800 it was deposited in the Conservatoire des Arts et Metier, Paris, where it still remains.
At a later period of his life, having lost his means of support, Cugnot’s public services were considered to entitle him to a reward from the State. Louis Fifteenth gave him a pension of six hundred livres, but the French Revolution coming on, he was deprived even of that pittance, and he lived in abject misery in Brussels. His carriage was then in the arsenal, and a revolutionary committee, during the reign of terror, tried to take it out and reduce it to scrap, but was driven off. When Napoleon came to the throne, he restored the pension and increased it to one thousand livres. In addition to his inventions, Cugnot wrote several works on military art and fortification.
William Murdock
Born in Bellow Mill, near Old Cumnock, Ayrshire, Scotland, August 21, 1754. Died at Sycamore Hill, November 15, 1839.
Murdock was the son of John Murdoch, a millwright. He was modestly educated, and brought up to his father’s trade, helping to build and put up mill machinery. A curious production of the father and son, at this period, was a wooden horse, worked by mechanical power, on which young Murdock traveled about the country. When he was twenty-three years of age he entered the employment of the famous engineering firm of Boulton & Watt, at Soho, and there remained throughout his active life.
Watt recognized in him a valuable assistant, and his services were jealously regarded. On his part he devoted himself unreservedly to the interests of his employers. In 1777 he was sent to Cornwall to look after the pumps and engines set up by the firm in the mines, and for a long period he lived at Redruth. For some five years after 1800 he was engineer and superintendent at the Soho foundry. While living at Redruth, in 1792, he began a series of experiments on the illuminating properties of the gases of coal, wood, peat, and other substances, and in 1799 put up a gas-making apparatus at Soho. In 1803 he fitted the Soho factory with a gas-lighting system. Other inventions that are credited to him are models for an oscillating engine and a rotary engine, a method of making steam pipes, an apparatus for utilizing the force of compressed air, and a steam gun.
WILLIAM MURDOCK
His early training and all his surroundings naturally and inevitably interested Murdock in the subject of steam locomotion, and before 1784 he began to experiment on these lines. That he made definite progress is shown in a letter that Thomas Wilson, agent in Cornwall of Boulton & Watt, wrote to his employers in August, 1786, saying, “William Murdock desires me to inform you that he has made a small engine of three-quarter-inch diameter and one and one-half inch stroke, that he has applied to a small carriage, which answers amazingly.” He had made and run this model in 1784, and it is still in existence, and in the possession of the Messrs. Richard and George Tangye, England.
This model was on the high-pressure principle, and ran on three wheels, the single front one for steering. The vertical boiler, nearly over the rear axle, was heated by a spirit-lamp, and the machine stood only a little more than a foot high. The axle was cranked in the middle and turned by a rod connected to a beam moved up and down by the piston-rod projecting from the top of the cylinder. Yet it developed considerable speed. It is interesting to note that the use of the crank for converting the reciprocating motion of the steam engine into rotary was patented by Pickard in 1780, and Murdock’s was probably its first application to self-propelled carriages.
The first experiment with this little engine was made in Murdock’s house at Redruth, when the locomotive successfully hauled a wagon round the room, the single wheel, placed in front of the engine, fixed in such a position as to enable it to run round a circle.
Dr. Smiles, in his work on inventors, tells an amusing story concerning this machine. He says: “Another experiment was made out of doors, on which occasion, small though the engine was, it fairly outran the speed of its inventor. One night, after returning from his duties at the mine at Redruth, Murdock went with his model locomotive to the avenue leading to the church, about a mile from the town. The walk was narrow, straight and level. Having lit the lamp, the water soon boiled, and off started the engine with the inventor after it. Shortly after he heard distant shouts of terror. It was too dark to perceive objects, but he found, on following up the machine, that the cries had proceeded from the worthy vicar, who, while going along the walk, had met the hissing and fiery little monster, which he declared he took to be the Evil One in propria persona!”
But Murdock was too useful a man to Boulton & Watt to be allowed to have free rein, and his inclination toward steam locomotion invention was apparently curbed, though it would appear Watt thought the roads of that time an insurmountable obstacle to the development of road vehicles, and wanted Murdock to devote his time to mechanical matters more ripe for success. Boulton, writing to Watt from Truro, in September, 1796, tells how he met Murdock on his way to London to get a patent on a new model, and how he persuaded him to turn back. This model was for a steam carriage that was afterward shown as able to travel freely around a room with a light load of shovel, poker and tongs upon it. His was probably the first high-pressure steam-engine vehicle run in England. Though only a small model, it did its proportionate work well.
Watt continued to oppose Murdock’s scheme, but on one occasion suggested that he should be allowed an advance of five hundred dollars to enable him to prosecute his experiments, and if he succeeded within a year in making an engine capable of drawing a post chaise, carrying two passengers and the driver, at four miles an hour, it was suggested that he should be taken as partner into the locomotive business, for which Boulton and Watt were to provide the necessary capital. This proposition was never carried out. Again, in 1786, Watt said: “I wish William could be brought to do as we do, to mind the business in hand, and let such as Symington and Sadler throw away their time and money in hunting shadows.” Murdock continued to speculate about steam locomotion on common roads, but never carried his ideas further. He retired from the employment of Boulton & Watt in 1830, and practically retired from all work at the same time.
Murdock seems to have had a very clear idea of the possibilities of steam propulsion on the