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FIRST INVENTORS OF LOCOMOTIVES.

CHAP. V. rather narrow, and was bounded on either side by high hedges. It was a dark night, and Murdock set out alone to try his experiment. Having lit his lamp, the water shortly began to boil, and off started the engine with the inventor after it. He soon heard distant shouts of despair. It was too dark to perceive objects; but he shortly found, on following up the machine, that the cries for assistance proceeded from the worthy pastor of the parish, who, going towards the town on business, was met on this lonely road by the hissing and fiery little monster, which he subsequently declared he had taken to be the Evil One in propriâ personâ. No further steps, however, were taken by Murdock to embody his idea of a locomotive carriage in a more practical form.

Richard Trevithick, a captain in a Cornish tin-mine, and a pupil of William Murdock,-influenced, no doubt, by the successful action of the model engine which the latter had constructed-determined to build a steam-carriage adapted for use on common roads. He took out a patent to secure the right of his invention in the year 1802. Andrew Vivian, his cousin, joined with him in the patent, -Vivian finding the money, and Trevithick the brains. The steam-carriage built on this patent 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 steamcocks 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 the first suocessful high-pressure engine constructed on the principle of moving a piston by the elasticity of steam against the pressure only of the atmosphere.

The steam-carriage excited considerable interest in the remote district near to the Land's End where it had been

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constructed. Being so far removed from the great movements and enterprise of the commercial world, Trevithick and Vivian determined upon exhibiting the machine in the metropolis. They accordingly set out with it to Plymouth, whence it was to be conveyed by sea to London. Coleridge relates, that whilst the vehicle was proceeding along the road towards the port, at the top of its speed, and had just carried away a portion of the rails of a gentleman's garden, Andrew Vivian descried ahead of them a closed toll-gate, and called out to Trevithick, who was behind to slacken speed. He immediately shut off the steam; but the momentum was so great, that the carriage proceeded some distance, coming dead up, however, just on the right side of the gate, which was opened like lightning by the tollkeeper. “What have us got to pay here?" asked Vivian. The poor toll-man, trembling in every limb, his teeth chattering in his head, essayed a reply-"Na-na-na-na ;”"What have us got to pay, I say?"-" No-noth-nothing to pay ! My de-dear Mr. Devil, do drive on as fast as you can! nothing to pay!" The carriage safely reached the metropolis, and was there publicly exhibited in an enclosed piece of ground near Euston Square, where the London and North-Western Station now stands; and it dragged behind it a wheel-carriage full of passengers. On the second day of the performance, crowds flocked to see the machine; but Trevithick, in one of his odd freaks, shut up the place, and shortly after removed the engine.

In the year following the exhibition of the steam-carriage, a gentleman was laying heavy wagers as to the weight which could be hauled by a single horse on the Wandsworth and Croydon iron tramway; and the number and weight of waggons drawn by the horse were something surprising. Trevithick very probably put the two things together-the steam-horse and the iron-way--and proceeded to construct his second or railway locomotive. It was completed in 1804, and tried on the Merthyr Tydvil Railway in South Wales. On the occasion of its first trial, the engine succeeded in dragging after it several waggons containing ten

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tons of bar-iron, at the rate of about five miles an hour. The boiler of this engine was cylindrical, flat at the ends, and constructed of cast-iron. The furnace and flue were inside the boiler, within which the single cylinder, of eight inches in diameter, and four feet six inches stroke, was immersed upright. As in the first engine, the motion of the wheels was produced by spur-gear, to which was also added a fly-wheel on one side. The waste steam was thrown into the chimney through a tube inserted into it at right angles; but it will be obvious that this arrangement was not calculated to produce any result in the way of a stoam-blast in the chimney; and, that Trevithick was not aware of the action of the blast in contributing to increase the draught, is clear from the fact that he employed bellows for this special purpose; and at a much later date (in 1815) he took out a patent which included a method of urging the fire by means of fanners.

Although the locomotive tried upon the Merthyr Tydvil Railway succeeded in drawing a considerable weight, and travelled at a fair speed, it nevertheless proved, like the first steam-carriage, a practical failure. It was never employed to do regular work, but was abandoned after a few experiments. It was then dismounted, and the engine was subsequently fixed and used to pump one of the largest pumps on the mine, for which work it was found well adapted.

Trevithick having abandoned the locomotive for more promising schemes, no further progress was made with it for some years. An imaginary difficulty seems to have tended, amongst other obstacles, to prevent its adoption and improvement. This was the supposition that, if any heavy weight were placed behind the engine, the "grip or "bite" of the smooth wheels of the locomotive upon the equally smooth iron rail must necessarily be so slight that the wheels would slip round upon the rail, and, consequently, that the machine would not make any progress.

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Following up the presumed necessity for a more effectual adhesion between the wheels and the rails than that pre

sented by their mere smooth contact, Mr. Blenkinsop, of Leeds, in 1811, took out a patent for a racked or tooth-rail laid along one side of the road, into which the toothedwheel of his locomotive worked as pinions work into a rack. The boiler of his engine was supported by a carriage with four wheels without teeth, and rested immediately upon the axles. The wheels were entirely independent of the working parts of the engine, and therefore merely supported its weight on the rails, the progress being effected by means of the cogged-wheel working into. the cogged-rail. Mr. Blenkinsop's engines began running on the railway extending from the Middleton collieries to the town of Leeds, a distance of about three miles and a half, on the 12th of August, 1812. They continued for many years to be one of the principal curiosities of the neighbourhood, and were visited by strangers from all parts. In the year 1816, the Grand Duke Nicholas (afterwards Emperor) of Russia observed the working of Blenkinsop's locomotive with curious interest and expressions of no slight admiration. An engine dragged behind it as many as thirty coal-waggons at a speed of about three miles and a quarter per hour.

The Messrs. Chapman, of Newcastle, in 1812, endeavoured to overcome the same fictitious difficulty of the want of adhesion between the wheel and the rail, by patenting a locomotive to work along the road by means of a chain stretched from one end of it to the other. This chain was passed once round a grooved barrel-wheel under the centre of the engine: so that, when the wheel turned, the locomotive, as it were, dragged itself along the railway. An engine, constructed after this plan, was tried on the Heaton Railway, near Newcastle; but it was so clumsy in its action, there was so great a loss of power by friction, and it was found to be so expensive and difficult to keep in repair, that it was very soon abandoned. Another remarkable expedient was adopted by Mr. Brunton, of the Butterly Works, Derbyshire, who, in 1813, patented his Mechanical Traveller to go upon legs, working alternately like those of

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a horse! But the engine never got beyond the experimental state, for, in one of its trials, it unhappily blew up and killed several of the bystanders. These, and other similar contrivances with the same object, projected about the same time, show that invention was actively at work, and that many minds were now anxiously labouring to solve the important problem of locomotive traction upon railways.

Mr. Blackett of Wylam, the owner of the colliery near which George Stephenson was born, was one of the most persevering in his efforts to introduce the locomotive as a working power instead of horses. He had an engine after Trevithick's patent made for him in 1811, but the road was too weak to carry it, and the engine was sold. In the following year he had a second engine made, to run upon a rack-rail like Blenkinsop's; but this too proved a complete failure. He persevered in building a third engine in his own workshops, and this, though clumsy and irregular in its movements-sometimes taking as much as six hours to haul the coal waggons the few miles down to the shipping place was regarded as on the whole tolerably successful. The road was in a bad state, and it often ran off the rails. As a workman observed one day, when asked how they got on-" We don't get on-we only gets off." On such occasions, the horses had to be sent out to drag on the waggons. The engine itself, constructed by incompetent workmen, often broke down; its plugs, pumps, or cranks got wrong; and then the horses were sent out to drag it back to the shop. Indeed, it became so cranky, that the horses were very frequently sent out following the engine, to be in readiness to draw it along when it gave up; and at length the workmen declared it to be "a perfect plague."

A story is still current at Wylam, of a stranger who was proceeding one dark evening down the High Street Road, as the "Puffing Billy" (so called after William Hedley, Mr. Blackett's viewer, a highly ingenious person) was seen advancing, puffing and snorting its painful and laborious way up from Newburn. The stranger had never heard

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