RICHARD TREVITHICK
In 1780 he built a double-acting high-pressure engine with a crank, for Cook’s Kitchen mine. This was known as the Puffer, from the noise that it made, and it soon came into general use in Cornwall and South Wales, a successful rival of the low-pressure steam vacuum engine of Watt.
As early as 1796 Trevithick began to give attention to the subject of steam locomotion, and a model constructed by him before 1800 is now in the South Kensington Museum. He busied himself in designing and building a steam vehicle to travel upon the common highways. The work was done in a workshop at Camborne, and some of it in the shop of Captain Andrew Vivian. It was Christmas Eve of 1801 when this steam locomotive was completed and was brought out for trial.
The following account of the first trial was made by one who was present: “I knew Captain Dick Trevithick very well. I was a cooper by trade, and when Trevithick was making his steam carriage I used to go every day into John Tyack’s shop at the Weith, close by here, where they put her together. In the year 1801, upon Christmas Eve, towards night, Trevithick got up steam, out on the high road, just outside the shop. When we saw that Trevithick was going to turn on steam, we jumped up, as many as could, maybe seven or eight of us. ’Twas a stiffish hill going up to Camborne Beacon, but she went off like a little bird. When she had gone about a quarter of a mile there was a rough piece of road covered with loose stones. She didn’t go quite so fast, and as it was a flood of rain, and we were very much squeezed together, I jumped off. She was going faster than I could walk, and went up the hill about half a mile further, when they turned her and came back again to the shop.” The next day the engine steamed to Captain Vivian’s house, and a few days subsequently, Trevithick and Vivian started off for Tehidy House, where Lord Dedunstanville lived, some two or three miles from Camborne. On this journey they met with an accident, the engine being overturned in going around a curve; but they got back safely.
This carriage presented the appearance of an ordinary stage coach on four wheels. The engine had one horizontal cylinder which, together with the boiler and the furnace-box, was placed in the rear of the hind axle. The-motion of the piston was transmitted to a separate crank-axle, from which, through the medium of spur-gear, the axle of the driving-wheel, which was mounted with a fly-wheel, derived its motion. The steam cocks and the force-pump, as also the bellows used for the purpose of quickening combustion in the furnace, were worked off the same crank axle. This was one of the first successful high-pressure engines constructed on the principle of moving a piston by the elasticity of steam against the pressure only of the outside atmosphere.
In the following year Trevithick went to London with his cousin, Andrew Vivian, and secured a patent. Early in 1803 he made his second steam carriage. This was built at Camborne and taken to London, via Plymouth, for exhibition. Its journey along the highways thoroughly alarmed the country people. Coleridge relates that a toll-gate keeper was so frightened at the appearance of the sputtering, smoke-spitting thing of fearsome mien that, trembling in every limb and with teeth chattering, he threw aside the toll-gate with the scared exclamation, “No—noth—nothing to pay. My de—dear Mr. Devil, do drive on as fast as you can. Nothing to pay!”
The engine in this carriage had a cylinder five and one-half inches in diameter, with a stroke of two and one-half feet, and with thirty pounds of steam it worked five strokes per minute. In every way it was superior to its predecessor. It was not so heavy; and the horizontal cylinder, instead of the vertical, added very much to its steadiness of motion; while wheels of a larger diameter enabled it the more easily to pass over rough roads which had brought the Camborne one to a standstill. The boiler was made entirely of wrought iron, and the cylinder was inserted horizontally, close behind the driving axle. A forked piston-rod was used, the ends working in guides, so that the crank axle might be brought near to the cylinder. Spur gearing and couplings were used on each side of the carriage for communicating motion from the crank shaft to the main driving axle. The driving-wheels were about ten feet diameter, and made of wood. The framing was of wrought iron. The coach was intended to seat eight or ten persons, and the greater part of the weight came on the driving axle. The coach was suspended upon springs.
The London steam carriage was put together at Felton’s carriage shop, in Leather Lane, and after its completion, Vivian one day ran the locomotive from Leather Lane, Gray’s Inn Lane, on to Lords’ Cricket Ground, to Paddington, and home again by way of Islington, a journey of ten miles through the streets of London. Several trips were made in Tottenham Court Road and Euston Square, and only once did they meet with accident. Finally, however, the frame of the carriage got twisted, and the engine was detached and set to driving a mill.
Trevithick’s next experiment was made in 1803-4, while he was engineer of the Pen-y-darran iron works, near Merthyr Tydvil, where he built and ran on a railway a locomotive that was fairly successful. In 1808 he built a locomotive for a circular railway or steam circus that he and Andrew Vivian set up in London, near Euston Square. This ran for several weeks, carrying passengers at the rate of twelve or fifteen miles an hour around curves of fifty or one hundred feet radius. One day a rail broke and the engine was overturned, which ended the exhibition.
Subsequently, Trevithick applied his high-pressure engine to rock-boring and breaking, and dredging. He laid out a system of dredging the Thames River, planned a tunnel under the Thames, invented a high-pressure steam threshing engine in 1812, constructed iron tanks and buoys, and modeled an iron ship. He was one of the first to conceive the practical use of steam in agriculture, declaring that the use of the steam engine for this purpose would “double the population of the kingdom and make our markets the cheapest in the world.”