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Chap. V. STEPHENSON STUDIES THE SUBJECT. 67
of the new engine, and was almost frightened out of his senses at its approach. An uncouth monster it must have looked, coming flaming on in the dark, working its piston up and down like a huge arm, snorting out loud blasts of steam from either nostril, and throwing out smoke and fire as it panted along. No wonder that the stranger rushed terrified through the hedge, fled across the fields, and called out to the first person he met, that he had just encountered a " terrible deevil on the High Street Eoad."
While Mr. Blackett was thus experimenting and building locomotives at Wylam, George Stephenson was anxiously brooding over the same subject at Killingworth. He was no sooner appointed engine-wright of the collieries than his attention was directed to the more economical haulage of the coal from the pits to the river side. We have seen that one of the first important improvements which he made, after being placed in charge of the colliery machinery, was to apply the surplus power of a pumping steam-engine, fixed underground, for the purpose of drawing the coals out of the deeper workings of the Killingworth mines,—by which he succeeded in effecting a large reduction in the expenditure on manual and horse labour.
The coals, when brought above ground, had next to be laboriously dragged by means of horses to the shipping staiths on the Tyne, several miles distant. The adoption of a tramroad, it is true, had tended to facilitate their transit: nevertheless the haulage was both tedious and expensive. With the view of economising labour, inclined planes were laid down by Mr. Stephenson, where the nature of the ground would admit of this expedient being adopted. Thus, a train of full waggons let down the incline by means of a rope running over wheels laid along the tramroad, the other end of which was attached to a train of empty waggons placed at the bottom of the parallel road on the same incline, dragged them up by the simple power of gravity—an exceedingly economical mode of working the traffic. But this applied only to a comparatively small portion of the entire length of road. An economical method 68 STUDIES THE CONSTRUCTION Chap. V.
of working the coal trains, instead of by means of horses— the keep of which was at the time very costly in consequence of the high price of corn,—was still a great desideratum; and the best practical minds in the collieries were actively engaged in the attempt to solve the problem. Although Mr. Stephenson from an early period entertained and gave utterance to his sanguine speculations as to the "travelling engine," this was his first practical object in studying it, and endeavouring to make it an effective power; and he now proceeded to devote the entire energy of his strong intellect to the subject.
First, he endeavoured to make himself thoroughly acquainted with what had already been done. Mr. Blackett's engines were working daily at Wylam, past the cottage where he had been born; and thither he frequently went to inspect Trevithick's patent engine, and observe the improvements which were from time to time made by Mr. Blackett, both in the locomotive and in the plateway along which it worked. He carefully inspected the "Puffing Billy," with its single cylinder and fly-wheel, its pumps, plugs, and spur-gear. After mastering its arrangements and observing the working of the machine, he did not hesitate to express his conviction that he could make a much better engine than Trevithick's—one that would draw steadier, and work more cheaply and effectively.
In the mean time he had also the advantage of seeing one of Blenkinsop's Leeds engines, which was placed on the tramway leading from the collieries of Kenton and Coxlodge, on the 2nd of September, 1813. This locomotive drew sixteen chaldron waggons containing an aggregate weight of seventy tons, at the rate of about three miles an hour. George Stephenson and several of the Killingworth men were amongst the crowd of spectators that day; and after examining the engine and observing its performances, he observed to his companions, that "he thought he could make a better engine than that, to go upon legs." Probably he had heard of the invention of Brunton, whose patent had by this time been published, and proved the subject of Chap. V. OF LOCOMOTIVES. 69
much curious speculation in the colliery districts. Certain it is, that, shortly after the inspection of the Coxlodge engine, he contemplated the construction of a new locomotive, which was to surpass all which had preceded it. He observed that those engines which had been constructed up to this time, however ingenious in their arrangements, had proved practical failures. Mr. Blackett's were both clumsy and expensive. Chapman's had been removed from the Heaton tramway in 1812, and was regarded as a total failure. And the Blenkinsop engine at Coxlodge was found very unsteady and costly in its working ; besides, it pulled the rails to pieces, the entire strain being upon the rackrail on one side of the road. The boiler, however, having shortly blown up, there was an end of the engine; and the colliery owners did not feel encouraged to try any further experiment.
An efficient and economical working locomotive engine, therefore, still remained to be invented; and to accomplish this object Mr. Stephenson now applied himself. Profiting by what his predecessors had done, warned by their failures, and encouraged by their partial successes, he commenced his labours. There was still wanting the man who should accomplish for the locomotive what James Watt had done for the steam-engine, and combine in a complete form the separate plans of others, embodying with them such original inventions and adaptations of his own as to entitle him to the merit of inventing the working locomotive, in the same manner as James Watt is regarded as the inventor of the working condensing engine. This was the great work upon which George Stephenson now entered, probably without any adequate idea of the immense consequences of his labours to society and civilization.
He proceeded to bring the subject of constructing a "Travelling Engine," as he then denominated the locomotive, under the notice of the lessees of the Killingworth colliery, in the year 1813. Lord Eavensworth, the principal partner, had already formed a very favourable opinion of the colliery engine-wright from the important improve
70 MAKES HIS FIRST LOCOMOTIVE. Chap. V.
ments which he had effected in the colliery engines, both above and below ground ; and, after considering the matter, and hearing Stephenson's statements, he authorized him to proceed with the construction of a locomotive,—though his lordship was, by some, called a fool for advancing money for such a purpose.
Mr. Stephenson had many obstacles to encounter before he could get fairly to work with the erection of his locomotive. His chief difficulty was in finding workmen sufficiently skilled in mechanics, and in the use of tools, to follow his instructions and embody his designs in a practical shape. The tools then in use about the collieries were rude and clumsy; and there were no such facilities as now exist for turning out machinery of an entirely new character. Mr. Stephenson was thus under the necessity of working with such men and tools as were at his command; and he had in a great measure to train and instruct his workmen himself. The engine was built in the workshops at the West Moor, the leading mechanic being John Thirlwall, the colliery blacksmith, an excellent workman in his way, though quite new to the work now entrusted to him.
In this first locomotive constructed at Killingworth, Mr. Stephenson to some extent followed the plan of Blenkinsop's engine. The boiler was cylindrical, eight feet in length and thirty-four inches in diameter, with an.internal flue tube twenty inches wide passing through the boiler. The engine had two vertical cylinders of eight inches diameter and two feet stroke let into the boiler, working the propelling gear with cross heads and connecting rods. The power of the two cylinders was continued by means of spurwheels, which communicated the motive power to the wheels supporting the engine on the rail, instead of, as in Blenkinsop's engine, to cogwheels which acted on the cogged rail independent of the four supporting wheels. This adoption of spur-gear was the chief peculiarity of the new engine; it worked upon what is termed the second motion. The chimney was of wrought iron, around which was a chamber extending back to the feed-pumps, for the Chap. V. MAKES HIS FIRST LOCOMOTIVE. 71
purpose of heating the water previous to its injection into the boiler. The engine had no springs whatever, and was mounted on a wooden frame supported on four wheels. In order, however, to neutralise as much as possible the jolts and shocks which such an engine would necessarily encounter from the obstacles and inequalities of the then very imperfect plateway, the water-barrel which served for a tender was fixed to the end of a lever and weighted, the other end of the lever being connected with the frame ot the locomotive carriage. By this means the weight of the two was more equally distributed, though 'the contrivance did not by any means compensate for the total absence of springs.
The wheels of the new locomotive were all smooth, and it was one of the first engines that had been so constructed. But before making the smooth wheels for his locomotive, Mr. Stephenson had the adhesion between the wheels of a loaded carriage and the rails tested and proved by experiment. He made a number of workmen mount upon the wheels of a waggon moderately loaded, and throw their entire weight upon the spokes on one side, when he found that the waggon could thus be easily propelled forward without the wheels slipping. He then determined to fix smooth wheels upon his locomotive, in the firm belief that the weight of the engine would of itself give sufficient adhesion for the purposes of traction.
The engine was, after much labour and anxiety, and frequent alterations of parts, at length brought to completion, having been about ten months in hand. It was placed upon the Killingworth Eail way on the 25th of July, 1814; and its powers were tried on the same day. On an ascending gradient of 1 in 450, the engine succeeded in drawing after it eight loaded carriages of thirty tons' weight at about four miles an hour; and for some time after it continued regularly at work. It was indeed the most successful working engine that had yet been constructed.
As the principal test of the success of the locomotive was its economy as compared with horse power, careful calcula