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chap. viii.] BLACKETT's LOCOMOTIVE EXPERIMENTS. 79
on a waggon, and there mounted upon the wooden frame supported by four pairs of wheels, which had previously been constructed for it. A barrel of water, placed on a rude frame supported by other two pairs of wheels, served as a tender. After a great deal of labour, the cumbrous and unsightly machine was got upon the road. But the engine would not move an inch! When the machinery was set in motion, Jonathan Foster says, “She flew all to pieces, and it was the biggest wonder i' the world that we were not all blewn up.” The useless engine was taken off the road and sold; and Mr. Blackett's efforts were thus far in vain. He was still, however, desirous of testing the practicability of employing locomotive power in railway traction, and he determined upon making yet another trial. Accordingly, he proceeded to build another engine under his own and Jonathan Foster's immediate inspection, in the Wylam workshops. The new engine had a single eight-inch cylinder, was fitted with a fly-wheel, the driving-wheel on one side being cogged, in order to enable it to travel in the rack-rail. This engine proved more successful than its predecessors. Although it was clumsy and unsightly, it was found capable of dragging eight or nine loaded waggons down to the shipping-place at Lemington. Its weight was, however, too great for the road, and the cast-iron plates were constantly breaking. Although this new locomotive was considered by Mr. Blackett to be an improvement upon horse traction, its working was by no means satisfactory. It crept along at a snail's pace, sometimes taking six hours to travel the five miles down to the loading place. It was also very apt to get off the rack-rail, and then it stuck. On these occasions, the horses had to be sent out to drag on the waggons as before. 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.” Mr. Blackett did not obtain any credit amongst his neighbours for these expensive experiments. Many laughed at his machines, regarding them only in the light of costly crotchets, —frequently quoting the proverb of “a fool and his money.” Others regarded them as absurd innovations on the established method of hauling coal; and pronounced that they would “never answer.” To some, indeed, they were the cause of considerable apprehension and alarm. 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 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 Road.” Notwithstanding the comparative failure of his locomotive thus far, Mr. Blackett persevered with his experiments. About 1813, he took out a patent in the name of William Hedley, his viewer, for a frame on four wheels on which to mount the locomotive engine. One of the first experiments which he made with this frame was, to test the adhe
chap. viii.] MR. BLACKETT's LOCOMOTIVE ExPERIMENTs. 81
sion of the smooth wheels of a carriage, properly weighted, upon the smooth rails of the road. Six men were placed upon the frame, which was fitted up with windlasses attached by gearing to the several wheels. When the men were set to work the windlasses, Mr. Blackett found that the adhesion of the wheels on the smooth rails was sufficient to enable them to propel the machine without slipping. Having then found the proportion which the power bore to the weight, he demonstrated by successive experiments that the weight of the engine would of itself produce sufficient adhesion to enable it to drag after it, on a smooth tramroad, the requisite number of waggons in all kinds of weather. Thus was the fallacy which had heretofore prevailed on this subject completely dissipated, and it was satisfactorily proved that rack-rails, toothed-wheels, endless chains, and legs, were alike unnecessary for the efficient traction of loaded waggons upon a moderately level road. As may readily be imagined, the jets of steam from the piston, blowing off into the air at high pressure while the engine was in motion, caused considerable annoyance to horses passing along the Wylam road, at that time a public highway. The nuisance was felt to be almost intolerable, and a neighbouring gentleman threatened to have it put down. To diminish the nuisance as much as possible, Mr. Blackett gave orders that so soon as any horse, or vehicle drawn by horses, came in sight, the locomotive was to be stopped, and the frightful blast of the engine thus suspended until the passing animals had got out of sight. Much interruption was caused to the working of the railway by this measure; and it excited considerable dissatisfaction amongst the workmen. The following plan was adopted to abate the nuisance: a reservoir was provided immediately behind the chimney, into which the waste steam was thrown after it had performed its office in the cylinder; and from this G.
reservoir, the steam gradually escaped into the atmosphere without noise.” This arrangement was devised expressly for the purpose of preventing any blast in the chimney, the value of which was not detected until George Stephenson, adopting it with a preconceived design and purpose, demonstrated its importance and value, – as being, in fact, the very life-breath of the locomotive engine.
* A drawing of the Wylam engine is given in the first edition of Nicholas Wood's Treatise on Railroads, 1825. The engine was placed on eight wheels, having seven rack-wheels working inside them, distributing the motion; while a barrel fixed behind the engine on two other wheels contained the water:—an exceedingly clumsy, uncouth-looking machine.
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