An original hardback
first published in 2002 by Fern House
19 High Street, Haddenham, Ely, Cambs CB6 3XA
© Copyright G C Stead 2002
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The right of Christopher Stead to be identified as the author of this work has been asserted by him in accordance with The Copywright, Design and Patents Act 1988
ISBN 1 902702 08 5
Chapter 7 The Locomotion
The Locomotion is perhaps the best known of the early railway engines, more striking even than the Rocket in its archaic appearance and construction. And it survives virtually unchanged, whereas the Rocket was largely rebuilt. Before describing it, something must be said about the Stockton and Darlington Railway for which it was constructed, the first steam-using public railway in England.
Like most early railways it was built to transport coal from the mines, though it soon came to carry other traffic. The Tyneside collieries had enjoyed the advantage of having a navigable river close at hand; those around Bishop Auckland were less fortunate. The River Wear at this point is fast-flowing and shallow; a well-known photograph taken at Durham, fifteen miles downstream, shows the Cathedral and the Castle with the river, still shallow, flowing over a weir. The coals would have to be carried eastwards to reach deep water on the Tees, quite close to its mouth near Stockton, before they could be shipped away.
The principal colliery at Witton Park lay about 450 feet up, near the Wear valley to the West of Bishop Auckland. The shortest route would have to rise to a summit level of some 650 feet at High Etherley, and then descend nearly 300 feet to cross the valley of the River Gaunless, a minor tributary of the Wear, near St Helen Auckland. It must then rise again to 450 feet to Brusselton summit before descending again to Shildon, near the later settlement of New Shildon, where locomotive working could begin. Thus four cable-worked inclines were needed west of Shildon, where the workshops were established, and later designed and built.
The length intended for locomotive working now ran to a point near the modern settlement of Newton Aycliffe. From here it would have been easy to continue eastwards to Stockton; but there were obvious advantages in taking the line close to Darlington, so it swung round southwards parallel to the Great North Road, the A1, and the later North Eastern Railway, to pass just north of the town, which was served by a short branch. The main line continued eastwards over what became the well-known level crossing with the main line to Edinburgh before turning north-east to reach Stockton. The distance was thus some 25 miles, as against 16 by the shortest possible route.
But this route was only settled after lengthy deliberations. A canal had been proposed as far back as 1768, but the scheme was unworkable, and by 1810 there was a counter-proposal for a tramway, backed by the influential Edward Pease. At a subsequent meeting John Rennie was commissioned to report, and once again recommended a canal. The decision is difficult to understand; whatever the route, it would have been impossible to avoid at least one long flight of locks, which could not fail to cause lengthy delays.
In any case, the promoters opinion was swinging back to some form of plateway or tramway; no doubt the successful operation of Stephensons inclined planes and locomotives on Tyneside and at nearby Hetton was already known. Thus in 1818, when a canal was once again proposed, Edward Pease and his allies protested. The promoters were won over, and agreed to commission a survey for a tramway or railway. They applied for parliamentary powers in 1819; the bill was thrown out by a small minority. A second attempt succeeded on 19 April 1821; the very same day George Stephenson and Nicholas Wood went to call on Edward Pease.
Pease was impressed by Stephensons air of competence and experience, and his straightforward unaffected manner. There was such an honest sensible look about George Stephenson, and he seemed so modest and unpretending, and he spoke in the strong Northumberland dialect. Pease himself was a man of some education, to the more fashionable you. Between them they succeeded in persuading the Board to decide for an edge railway, in preference to a plateway, and Stephenson was commissioned to make a survey, revising and improving the route previously recommended by George Overton. Favoured by excellent weather, the survey was rapidly completed in the autumn of 1821, and the plans, estimate and report were presented next January. The charge for the survey was the modest figure of £140, and the estimated cost of the new line was a little under £61,000, about £2,400 per mile.
Stephenson had time now to consider the provision of locomotives, in consultation with his son Robert, who had already assisted him on the survey, and who founded the well-known locomotive building works in 1823. The locomotives in use at Hetton and elsewhere followed the pattern adopted in 1816, with vertical cylinders working twin connecting rods, chain coupling of the driving wheels, and steam springs. There had been gradual improvement in performance, but speeds seldom exceeded 10mph, and something more versatile was called for on a line expected to carry passengers as well as goods. Drawings have now been discovered which show that several new plans were considered before the Locomotion attained its final form. It followed George Stephensons established practice in its main conception but had some interesting new features.
It retained Stephensons original design of boiler with a single straight flue. This was by no means efficient, but it was simple and cheap to construct. The violent rush of hot gas through the due to the blast pipe was sufficient to sustain a brisk fire, at the cost of throwing much red-hot coal out of the chimney. The waste of fuel did. not matter too much in a district where it was cheap and plentiful, the rain of hot cinders on the passengers heads had simply to be endured.
There were three main innovations. First the steam springs were abandoned. It was a year or two before reliable plate springs became available, so the engine was unsprung. Perhaps it was thought that a newly laid track could be made sufficiently firm to accept unsprung locomotives without inconvenience; expense and maintenance trouble could thus be avoided, and there would be no interference with the regular motion: of the, pistons. This again should have led to a great improvement in the efficiency of the cylinders, if no extra space had to be allowed at the two en to ensure that the pistons did not strike them, the length of the cylinders could be tailored to fit the working stroke of the engine, and a great waste of steam avoided. This single fact may have been enough to account for Locomotions advantage in power over Stephensons earlier machines; though it may have ridden very roughly as the track began to show the effects of wear and distortion. Next, the chain coupling was discontinued. It was of course impossible to use connecting rods without special provision, since the two cylinders and their crankpins were not moving in phase. But by now Stephenson was sufficiently confident of his manufacturing skill or his sons! to use a return crank, which set up a secondary coupling pin at an angle of 90º from the main crank-pin, and enabled connecting rods to be used. Hackworth had apparently designed this innovation.
The most remarkable departure from precedent, however, was the, revival of parallel motion in preference to the slide bars which Stephenson: had, invariably used hitherto. This has been condemned as a retrograde move; but a possible reason for, the change may be suggested. The railway was intended to carry passengers. and the Stephensons must have envisaged higher speeds than the 10 mph or so already achieved; in fact Locomotion on her trial run attained 25 mph with a very considerable load. Lubrication was still something of a problem; and it may have been thought that cross-heads moving at high speeds along slide-bars would overheat and jam. A guidance system provided by pivoted rods would be far more complex, but the lubrication of the pivots would present no problems, as the friction would be small.
At all events, parallel motion was quickly, though briefly, adopted, by other designers. Besides Locomotion and her sisters, four engines in all, it appeared on Hackworth's Royal George of 1827; on Hedley's rebuilds of the Puffing Billies, some time, between 1825 and 1830; on at least two half-beam engines, the Stourbridge Lion, by Foster and Rastrick, which went to America; on the very similar Agenoria; and on Marc Séguin,'s eccentric 040 in France.
To the casual onlooker Locomotion presents a bewildering tangle of rods on the top of its boiler. Four sets of parallel motion had to be provided, to guide both ends of the two cross-heads. The piston-rods, cross-heads and descending connecting-rods are easily identified. Between them lay a fixed rectangular structure of rods with diagonal bracing. Its purpose was to provide fixed points for the pivots of four rods which pointed inwards towards the centre of the engine. These again were pivoted to four much longer rods which swung from pivots quite close to the centre. Obviously these pivots could not be fixed, as their distance from the intersection with the shorter rods must vary; they were carried on four nearly vertical rods pivoted on top of the boiler. This allowed the upper pivots to swing to and fro for a few inches as the rods assumed their varying positions, The outer ends of the longer rods were attached to the cross-heads, and as their motion was controlled by two opposing arcs (struck from pivots near the ends of the engine, and near its centre), they kept the cross-heads and piston-rods moving vertically up and down, as required.
The cylinders were provided with slide valves with a stroke of two inches, operated by two slip eccentrics fixed on the same axle; the rods which work them can be seen slanting up the sides of the boiler. The boiler itself was relatively large, with a diameter of 4ft 4in and a length of 11ft 6in; the flue tube was 2ft 1in in diameter. The piston-rods were 5ft 1in apart, which of course was also the length of the wheelbase. The wheels were of cast iron, of a form which had to be adopted owing to the limited capacity of the lathes at Shildon, with an inner disc 2ft 6in diameter and an outer ring of 3ft 11in, keyed with wooden wedges. The well-known photographs show the wheels as discs provided with 12 spokes projecting from the plane surface, and with circular holes in the outer rings to tighten the weight.
Locomotion made its trial trip at Newcastle on 11 September, 1825, and the Opening Day was fixed for the 27th of that month. The engine was drawn by horses to Heighington Lane, near Aycliffe, a few days later, and there unloaded. Just before the opening day the first passenger coach, the Experiment, was delivered at New Shildon; the locally built body was fitted onto, an unsprung frame built at Robert Stephensons works at Newcastle. A trial trip was made with this coach from Shildon to Darlington on the 26th, and all was ready for the grand ceremonies of the next day.
Long before dawn thousands of people began to converge on the railway, especially at Shildon, where the locomotive was awaiting its train; for the cable-worked inclines were also included in the demonstration. Ten loaded coal wagons were brought by horses from the Phoenix Colliery at Witton Park to the Etherley incline and worked by cable over the summit and down to the level stretch extending across the Gaunless valley near St Helens Auckland. A wagon-load of flour was attached, and the train of eleven wagons was drawn by horses to the foot of Brusselton incline then by cable over the summit, and down to New Shildon. Here the Locomotion stood waiting, attached to the passenger coach and twenty-one new coal wagons fitted with temporary seats. The trains were coupled together, making thirty-three vehicles in all. So far the proceedings had gone without a hitch.
The promoters however had not expected the enormous crowd which had collected, many of them determined on a ride. Three hundred seats had been reserved, but many more forced their way onto the train; the total number has been variously estimated at 400 to 600 people; the train measured 450 feet in length and must have weighed some 90 tons.
Trouble set in almost at once. After a few hundred yards a wagon derailed; when lifted on it immediately came off again, and had to be shunted off the track. The train went on to Simpasture, three miles from the start; but here Locomotion herself was the culprit; a piece of oakum had fouled one of the valves of the feed pump. Stephenson removed it and reported that all was now well; and the train completed the 81/2, miles to the Darlington junction in 65 minutes, an average of 3mph, admittedly helped by a slight favouring grade.
At the junction a crowd of 12,000 people were waiting. Six of the coal wagons were shunted off for distribution to the poor of Darlington, and two others picked up. The eleven miles or so to Stockton were more difficult going, with some adverse grades; an average speed of four mph was maintained, but this perhaps includes a stop at Goosepool for water. Finally the train clanked over St Johns crossing on to Stockton quay, to a tumultuous welcome from some 40,000 spectators. Arrival was 45 minutes late, but as 55 minutes had been lost by earlier delays, there was nothing to count against the engine.
The inevitable official banquet followed at the Town Hall, lasting till midnight, after which Stephenson must have retired to bed well satisfied with the days work.
The triumphant opening day made a great impression on the public. But sadly, some years of frustration and confusion followed. Locomotion herself broke a wheel shortly after the Opening Day. Hope, the next in the class, arrived late and was found to be defective. Two of the Locomotion class exploded, no doubt because of careless handling. More troublesome, perhaps, were the difficulties which sprang from the railways conception as a public highway. Coal traffic expanded rapidly; the single line soon proved inadequate; horse-drivers with their trains were obstinate and refused to give way as they should have done at the passing places; their wagons were ill-constructed, and the buffers and couplings did not match. Over some years the troubles were gradually resolved, the private traders were bought out and the wagons standardised. The line was doubled from Stockton to Brusselton by 1832, and its working began to resemble that of the much larger Liverpool and Manchester Railway, for which it had prepared the way. Stephenson at least was convinced that the new line must be a track reserved for the companys vehicles. Many landowners were enraged by the compulsory passage-way across their estates; their opposition had to be endured, by-passed, or bought off. Fortunately the enormous cost was soon repaid by heavy and profitable traffic.