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placed at the bottom of the parallel road on the same incline, dragged them up by the single 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 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 practical 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 in which he had been born; and thither he frequently went, sometimes in the company of Nicholas Wood, 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 “Black 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 declare to Jonathan Foster on the spot, his firm 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 meantime he had also the advantage of seeing one of Blenkinsop's Leeds engines, constructed by Fenton Murray and Wood, of that town. The engine was a very

chap. Ix.] THE COXLODGE ENGINE. 85

excellent piece of workmanship, and a great improvement upon the clumsy machines which Mr. Stephenson had inspected at Wylam. It was placed on the tramway leading from the collieries of Kenton and Coxlodge, on the 2nd of September, 1813; and a large concourse of spectators assembled to witness its first performances. 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, as related by Heppel, who was present, 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 much curious speculation in the colliery districts. Certain it is that, shortly after the inspection of the Coxlodge engine, Stephenson 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 rack-rail 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 important 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 civilisation. 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 Ravensworth, the principal partner, had already formed a very favourable opinion of Stephenson, from the important improvements which he had effected in the colliery engines, both above and below ground; and, after considering the matter, and hearing Stephenson's statements, he authorised 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. “The first locomotive that I made,” said Mr. Stephenson, many years after", when speaking of his early career at a public meeting in Newcastle, “was at Killingworth colliery, and with Lord Ravensworth's money. Yes, Lord Ravensworth and partners were the first to entrust me with money to make a locomotive engine. That engine was made thirty-two years ago, and we called it “My Lord.”

* Specch at the opening of the Newcastle and Darlington Railway, June 18th, 1844.

cHAP. IX.] MAKES HIS FIRST LOCOMOTIVE. 87

I said to my friends, there was no limit to the speed of such an engine, if the works could be made to stand it.” Mr. Stephenson had, however, many serious difficulties to encounter before he could get fairly to work with the erection of his locomotive. His chief difficulty was in finding mechanics sufficiently skilled in the knowledge of machinery, and in the use of tools, to follow his instructions and embody his designs in a practical shape. Skilled mechanics were few in number in those days, and were for the most part confined to Birmingham, Manchester, Leeds, and London. The tools in use about the collieries were rude and clumsy; and there were then 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 feedpumps, for the 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 of 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 the first engine that had been so constructed. From the first, Mr. Stephenson was convinced that the adhesion between a smooth wheel and an edgerail would be as efficient as Mr. Blackett had proved it to be between the wheel and the tramroad. And, although everyone at that time argued that the adhesion upon a tramrail was by no means a criterion of what the adhesion would be upon an edgerail, Mr. Stephenson felt confident that there was no essential difference between the one and the other. Before, however, constructing the smooth wheels for his locomotive, he had the adhesion between the wheels of a carriage, properly loaded, and the rails, tested and satisfactorily proved by experiment. He made a number of workmen mount upon the wheels of a waggon moderately loaded, resting their entire weight upon the spokes on one side, and 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.

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