Fig. 50.—Trevithick’s Locomotive, 1804.
In the year 1808, Trevithick built a railroad in London, on what was known later as Torrington Square, or Euston Square, and set at work a steam-carriage, which he called “Catch-me-who-can.” This was a very plain and simple machine. The steam-cylinder was set vertically in the after-end of the boiler, and the cross-head was connected to two rods, one on either side, driving the hind pair of wheels. The exhaust-steam entered the chimney, aiding the draught. This engine, weighing about 10 tons, made from 12 to 15 miles an hour on the circular railway in London, and was said by its builder to be capable of making 20 miles an hour. The engine was finally thrown from the track, after some weeks of work, by the breaking of a rail, and, Trevithick’s funds having been expended, it was never replaced. This engine had a steam-cylinder 141∕2 inches in diameter, and a stroke of piston of 4 feet. Trevithick used no device to aid the friction of the wheels on the rails in giving pulling-power, and seems to have understood that none was needed. This plan of working a locomotive-engine without such complications as had been proposed by other engineers was, however, subsequently patented, in 1813, by Blackett & Hedley. The latter was at one time Trevithick’s agent, and was director of Wylam Colliery, of which Mr. Blackett was proprietor.
Trevithick applied his high-pressure non-conducting engine not only to locomotives, but to every purpose that opportunity offered him. He put one into the Tredegar Iron-Works, to drive the puddle-train, in 1801. This engine had a steam-cylinder 28 inches in diameter, and 6 feet stroke of piston; a boiler of cast-iron, 63∕4 feet in diameter and 20 feet long, with a wrought-iron internal tube, 3 feet in diameter at the furnace-end and 24 inches beyond the furnace. The steam-pressure ranged from 50 to 100 pounds per square inch. The valve was a four-way cock. The exhaust-steam was carried into the chimney, passing through a feed-water heater en route. This engine was taken down in 1856.[48]
In 1803, Trevithick applied his engine to driving rock-drills, and three years later made a large contract with the Trinity Board for dredging in the Thames, and constructed steam dredging-machines for the work, of the form which is still most generally used in Great Britain, although rarely seen in the United States—the “chain-and-bucket dredger.”
A little later, Trevithick was engaged upon the first and unsuccessful attempt to carry a tunnel under the Thames, at London; but no sooner had that costly scheme been given up, than he returned to his favorite pursuits, and continued his work on interrupted schemes for ship-propulsion. Trevithick at last left England, spent some years in South America, and finally returned home and died in extreme poverty, April, 1833, at the age of sixty-two, without having succeeded in accomplishing the general introduction of any of his inventions.
Trevithick was characteristically an inventor of the typical sort. He invented many valuable devices, but brought but few into even experimental use, and reaped little advantage from any of them. He was ingenious, a thorough mechanic, bold, active, and indefatigable; but his lack of persistence made his whole life, as Smiles has said, “but a series of beginnings.”
It is at about this period that we find evidence of the intelligent labors of another of our own countrymen—one who, in consequence of the unobtrusive manner in which his work was done, has never received the full credit to which he is entitled.