The Locomotive Pioneers: Early Steam Locomotive Development 1801–1851
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Anthony Burton
ANTHONY BURTON is an author specialising in the history of technology and transport. His books for The History Press include The Anatomy of Canals, The Iron Men, Miners, Navvies, and The Workers’ War. Other books include biographies of Thomas Telford, Richard Trevithick, George and Robert Stephenson and Marc and Isambard Brunel. He has been involved in over 100 TV documentaries, half as writer/presenter and others as historical adviser, including The Past at Work for the BBC and appeared as a guest expert on Coast, Reel History and Big, Bigger, Biggest. More recently he has been Historical Adviser for six ten-part series for Discovery that have involved visiting industrial sites in both Europe and America. He lives in Stroud.
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The Locomotive Pioneers - Anthony Burton
Acknowledgements
The author would like to thank Michael Bailey for permission to quote from his article on the Planet replica and the following for permission to use illustrations. Where no acknowledgement is given the illustrations are either from the author’s own collection or taken from out of copyright documents and books.
Baltimore & Ohio Railroad Museum, 131; Best friend of Charleston Museum, 94; Ben Brookshaw, 111; Birmingham Museum & Art Gallery, 8; Canterbury Heritage Museum, CFV3V Mariemborg, 98, 100; Cité du Train, 139, 144; City & Council of Swansea, Museum Collection, 39; Darlington Railway Museum, 53; DB Museum von Verkhermuseum, Nurmberg, 104, 147; Ffestiniog Railway, 153; Gil Scott, 14; Franklin Institute, Philadelphia, 129; John Minnis, 17; Mansell Collection, 34; Martin Bell, 67; Museo Nationale Ferroviano, 138; Museum of Science & Industry, Chicago, 85; Museum of Science & Industry, Manchester, 80; North of England Open Air Museum, Beamish, 26, 48; Nova Scotia Museum of Industry, 96; Science & Society, 65, 66, 107, 161, 182; Simon Cook, 21; Smithsonian Institute, 179; Steam Museum, Straffan, 10; Steam, Swindon, 162, 172 (bottom); Swindon Borough Council, 159; Trevithick Society, 11; Trustees of the National Museum of Scotland, 27; University of Atacama, 130.
Preface
My interest in early locomotives, as opposed to railway history in general, was first aroused when I was invited to write and present the BBC TV series The Past at Work. Although the series was about the remains of the Industrial Revolution and we had set ourselves a terminal date of 1825, it did provide an opportunity to look at two iconic railways: the Middleton Colliery, the world’s first successful commercial line and the Stockton & Darlington. Shortly afterwards I was again working with BBC TV, this time on The Rainhill Story, in which we followed the construction of the replicas of the three engines that took part in the original trials. I can vividly remember the excitement of being present when a fire was lit in a boiler for the first time, and the splendid replica steamed off or – in the case of Novelty – tottered off. My next major involvement came when I decided to write a biography of Richard Trevithick and once again became involved with seeing working replicas come to life. There was an exciting, if bone-shaking ride on the 1801 road locomotive and a rather more dignified journey in the astonishing London road carriage, where I shared the experience with Frank Trevithick Okuno, a direct descendant of the great man. Best moment of all came when I was invited onto the footplate of the replica of the 1803 engine at the Ironbridge Gorge Open Air Museum and was invited to drive, though, to be honest, I did nothing more than open and close the regulator but that made it none the less thrilling.
These varied experiences gave me a new appreciation of just how inventive the early engineers were, who had to devise these engines for themselves with no precedents to work on. It also showed me how well they had done their work, for each of these engines from Trevithick’s first attempt right up to Rocket a quarter of a century later, impressed by their mechanical ingenuity and by their performance. So when I was invited to write this book, there was no hesitation. I am grateful to John Scott Morgan for issuing the invitation and for his help and encouragement, not least for his assistance in providing many of the illustrations. Needless to say, any errors that readers find are entirely my own. I should also like to say a special thank you to Michael Bailey, firstly for allowing me to quote him at length on the working of the Planet replica. His own book Loco Motion appeared shortly after I started my research, and it proved invaluable for the technical details it listed on early, surviving locomotives.
Finally, a word about units: I have used the units in use at the time, rather than their modern equivalents. A British engineer, for example, would never have designed a locomotive with a 38.1 cm diameter cylinder, but he would have taken a great deal of care to make sure it was manufactured as close to 15 inches as possible.
Chapter One
Before the Railways Came
The work of the men who designed and built the world’s first locomotives represents a quite extraordinary achievement. To understand just how significant it really was, one has to look at the transport situation in Britain at the dawn of the railway age. The latter part of the eighteenth century had seen a revolution in transport, with the development of the canal system. It was, at the time, the most efficient and cheapest way of moving goods from place to place. Experiments carried out by two of the leading engineers of the day, John Smeaton and Thomas Telford, compared the loads that could be moved by a single horse. The best results for a waggon on one of the new, surfaced roads was two tons, whereas on a canal the horse could pull a load of fifty tons – though in practice, the narrow boats in use on much of the system could only hold around twenty-five tons. It is easy to see why the canal engineers felt that they had achieved a massive improvement in the transport of goods and saw no reason to look for other solutions. Telford was to go so far as to argue that the only point of railways was to bring goods down to canals and rivers. Canals, however, had very little impact on passenger travel, which still relied almost entirely on stage-coaches. Thanks to road improvements, journey times had been cut drastically from those of the mid-eighteenth century. Telford had overseen the reconstruction of the London-Holyhead road, work that included the building of the two great suspension bridges at Conway and the Menai Straits. As a result, the fast mail service on the 261 mile route was set at 26 hours and 55 minutes and that included 27 stops to change horses and just one 40-minute meal break. It was the ultimate in travel by horse-drawn vehicles. It represented, however, only the very best that stage-coach travel could offer: ordinary stage-coaches moved at a more leisurely pace. The experience of stage-coach travel was to be undergone rather than enjoyed. Travellers could either pay top fares to sit inside or travel more cheaply on top, out in the open with no protection from the weather. Even inside travel was rarely comfortable. In the more cramped carriages, passengers sat bolt upright, three to a seat, elbows jostling and knees almost touching the three sets of knees opposite. Doctor William Kitchiner, writing as late as 1827 in his book The Traveller’s Oracle gave this advice to outside passengers:
‘If circumstances compel you to ride on the outside of a Coach, put on Two Shirts and Two Pairs of Stockings, turn up the collar of your Great Coat and tie an handkerchief round it, and have plenty of dry Straw to set your feet on.’
This was probably sound advice that had not been taken by two outside passengers on the London to Bath coach in 1812 who, when the coach stopped at Chippenham, were found to have frozen to death. We have become used to seeing jolly scenes on Christmas cards of merry travellers at coaching inns keenly looking forward to the excitement of the journey. Reality was a good deal less romantic. At the peak of the coaching age, there were some 4,000 coaches in regular service in Britain. Considering that the largest coaches could only carry six inside passengers and ten outside, it is obvious that travel was strictly limited by both the high cost and the number of vehicles. But just to keep this service running required 150,000 horses, and it is difficult to see how major changes could ever occur – there was simply not enough capacity to keep and feed more animals. It was a system that would either stagnate or be transformed by a totally different transport system. There was, however, a hint of a new solution in those experiments by Smeaton and Telford mentioned earlier. The largest load that could be drawn by a single horse on land was only possible if the waggon ran on iron rails, when it rose from two tons on an ordinary road to eight tons. It was a system widely used on the tramways that acted as feeders for canals and rivers. These were designed to be worked by horses, and to allow space for the animals to walk, the cast iron rails were mounted on square, stone sleeper blocks. Steam engines were in use on some, but these were massive stationary engines, used for haulage up and down steep inclines. It was on just such a tramway that the very first railway locomotives were to run, as we shall see in the next chapter.
By the end of the eighteenth century Britain was already well into that great technological upheaval known as the Industrial Revolution. This was the new technological age, in which work that had once been carried out in homes and small workshops had moved to factories and mills thanks to the development of machines. Yet very little that had been achieved was due to the work of academically trained scientists and engineers. Compared with other countries, particularly France, Britain had virtually nothing to offer in the way of formal training in any branch of technology. James Sims expressed the situation perfectly in his book, The Mining Almanack for 1849:
Typical coal waggons or chaldrons of the north eastern tramways at the Beamish Open Air Museum.
‘Amongst all the heroes and all the statesmen that have ever yet lived none have ever accomplished anything of such vast importance to the world as large as have been realised by a few simple mechanics.’
This was initially true to a certain extent of the men who designed and built the first locomotives. None of them came from an academic background nor had they any scientific education – but then neither did most ‘educated’ gentlemen in Britain. The first engineers were practical men dealing with practical problems on a day-to-day basis. They had few specialist tools to rely on and knew little, if anything, of theory. Yet in just a few years they transformed the world of transport. This book tells the story of these men, some of whom have become famous and others, who made vital contributions, have been largely forgotten. And although it is customary to speak of such-and-such an engineer as having built a particular locomotive, that does not, of course, mean that they personally machined the parts and assembled them. That was the job of some highly skilled mechanics who should also be honoured among the list of locomotive pioneers; as should those who designed the increasingly sophisticated machine tools that made the whole process possible.
Stage coach travel has always had a rather romantic image, but as this illustration by the eighteenth century artist W. H. Pyne shows it was far from comfortable for many passengers, and four horses were needed to move fewer than a dozen people.
The story of the birth and development of the railway locomotive is also the tale of the lingering demise of the stage-coach, and an anonymous Victorian author wrote this obituary:
‘Died after a long and protracted existence, the near leader of the Red Rover
, the last of the London and Southampton coaches. The symptoms of decay, which ended in the event we now record, set in on the day the South Western Railway opened, the severe grief produced by which brought on an affection of the heart, which upon a frame not of the strongest, induced the calamity, so much deplored by the inconsolable proprietors’
Chapter Two
Steam on the Move
The first practical steam engines were developed to pump water from mines, and the most successful of these was the machine invented by Thomas Newcomen at the beginning of the eighteenth century. It was a beam engine, in which the pump rods were attached to one end of an overhead beam and their weight automatically dragged that end down. What was needed was a force that could be applied to the opposite end of the beam to pull that end down and thus raise up the pump rods. In Newcomen’s engine this was achieved by means of passing steam into a cylinder fitted with a piston attached to the beam by a chain, then spraying the cylinder with cold water to condense the steam. This created a partial vacuum and air pressure would force the piston down. It did the job but was very inefficient. It was James Watt who recognised that the problem was caused by the constant repetition of heating and cooling the cylinder. His solution was to condense the steam in a separate vessel, so that the cylinder could be kept permanently hot. There was still a difficulty with heat loss from the open topped cylinder, and he dealt with this by closing the top and replacing air pressure with steam pressure. The atmospheric engine had become a genuine steam engine.
The first engines built by the company formed by Watt and the Birmingham industrialist Matthew Boulton, were single acting. As the connection between piston and beam was still by means of a chain, the piston could only pull down, not push up. It was Boulton who urged Watt to find some means of making a double-acting engine that could be used for a far greater variety of tasks. The difficulty was caused by the fact that the piston needed to go straight up and down in the cylinder, but a straight connection to the end of a beam moving through the arc of a circle made this impossible. Watt came up with what he always referred to as his greatest invention: the parallel motion. In effect, the piston was now suspended from a parallelogram of shifting rods. The device was first produced in 1784 and was soon being applied to produce rotative engines that could be used to turn the wheels and shafts that would power the machinery in mills and factories.
Watt had a patent that lasted until the end of the eighteenth century and effectively prevented anyone else from experimenting with steam engines, at least in theory, though a number of ‘steam pirates’ tried to get away with inventing new engines of their own. It was not just the all-embracing patent that discouraged innovation, but Watt himself had very firm views on how a steam engine should be operated. To him, high-pressure steam was anathema: if you wanted more power then you simply built a bigger engine. That was fine in some respects, but it ruled out any possibility of using the engine in the world of transport. There was no way a massive beam engine, weighing several tons and standing twenty feet or more high, was about to go trundling off down the road. But Watt’s writ did not run in France, and there a former army officer had different ideas.
Nicolas Joseph Cugnot had fought throughout the Seven Years War and when he retired from the army in 1763 he began to think of how steam power could be used in warfare. Moving artillery had always required a team of horses and skilled handlers and he felt that the job would be more efficiently performed using a steam tractor. He built a prototype in 1769 and followed it up with a more refined version a year later, and the original machine is still preserved in the Musée des Arts et Métiers in Paris. It was a cumbersome affair, mounted on three wheels with a massive copper boiler overhanging the single front wheel, supplying steam to two cylinders mounted to either side. It was successful in that it proved capable of towing a load of five tonnes at a brisk walking pace, but it could not keep going: it had to be stopped at regular intervals and allowed to cool down so that the boiler could be refilled. It had no brakes and proved difficult to steer, hardly surprising since the steering was through the front wheel, overhung by the heavy boiler. A probably apocryphal story has it that on one of the inaugural runs it got out of control and demolished a brick wall, at which point the authorities banned it from the streets. It was never developed; the project was simply abandoned and it is doubtful if many people outside French military circles ever heard about it. It certainly seems unlikely that the news ever reached England where the next development of steam power on the road was to take place.
The Boulton & Watt steam engine had been a great success in the tin and copper mines of Cornwall. The powerful pumps enabled miners to go to ever-greater depths to recover valuable ore deposits, and the improved efficiency over the previous Newcomen engines was of huge significance in a region where coal had to be imported from other areas such as South Wales. But the Cornish mine engineers were a very independent minded body of men. They were used to making their own decisions and working on their own new developments. They had earlier found ways of improving the efficiency of the atmospheric engines, but now they were prevented by the patent from even considering improvements to the Boulton & Watt engines. This rankled and several local men began working on new ideas. Among them was a young engineer called Richard Trevithick. Born in 1771, he was fascinated by steam from an early age – and his father, Richard Trevithick Snr., was one of those who had improved early engines. The son followed the same career as his father, becoming a mine captain, the chief engineer at the mine, while still in his twenties.
Even as a child he showed his impetuous nature; when he was told off by his teacher for not showing how he had arrived at the answer to the sums he’d been told to do, he simply pointed out that he didn’t need to and could do six sums while his teacher did one. It might have been true, but hardly endeared him to the school, which might explain the school report that described him, among other things, as ‘inattentive’ and ‘frequently absent’. The absence was easily explained – he was more interested in spending his time around the machinery at the local mine, puzzling out how everything worked. The report also mentioned his obstinacy, which was certainly a trait of his character which, combined with a rather short temper, was to be a factor in many of his dealings with others. This was exemplified later in his career, when he had devised a new way of salvaging sunken vessels, by attaching iron tanks that were then pumped full of air. He used it successfully to lift a vessel at Margate, but when it was raised the owners demanded that he also had it towed to harbour before they would pay. Trevithick pointed out that he had only been contracted to raise the vessel and he’d need an extra payment for arranging the tow; the owners refused. Trevithick ordered his men to cut off the tanks and the vessel subsided back to the seabed. It was a typically quixotic gesture, which made a point, but lost him his fee. He was not always able to see where his own best interests lay. And from the first, he was always one to go his own way, regardless of opposition.
The family had several legal tussles with Boulton & Watt. In particular, Trevithick had worked with another engineer, Edward Bull, in developing a pumping engine that was worked on a different principle, being inverted over the shaft to work directly. Boulton and Watt won a court case against Bull and got an injunction against his continuing to work with his experiments, but Trevithick was not included in the injunction. There was a famous story at the time of a bailiff being sent to serve a paper on the engineer, but being picked up and suspended over an open mine shaft before agreeing that, on the whole, he would like to go home, taking his papers with him. Trevithick eventually became over confident and actually visited Birmingham, where the manufacturers had their base; he was recognised and served with the injunction.
The legal battles left a bitter legacy of enmity between the two camps, and Boulton and Watt were never to lose the opportunity to disparage anything Trevithick might aspire to do. But by the 1790s young Richard was already entertaining some new and very revolutionary ideas. He was starting to think about using high-pressure steam. He began to wonder if it was actually necessary to use a condenser at all, but whether he could simply allow the exhaust steam to blow out into the atmosphere. He was a practical man with no scientific training, but he had a friend, Davies Gilbert, who was ready and willing to advise him. ‘What’, asked Trevithick, ‘would be the loss of power in working an Engine by the force of Steam raised to the Pressure of several Atmospheres, but instead of condensing it let the steam escape?’ Gilbert was able to assure the engineer that the only power that would be lost could never exceed one atmosphere or, in other words, it would never be more than 14.7 pounds per square inch (psi) – 100 kilopascals in today’s units. Trevithick was understandably delighted and set to work, and he was more than able to compensate for the loss of one atmosphere by having engines working at a boiler pressure of 60psi. He began to think not just of manufacturing compact engines, small enough to be transported to where they were needed, but also considered engines that could move themselves. He began by making a simple model that was given a first outing on the kitchen table in his own home, where the boiler was simply, in his own words, ‘a strong iron kettle’. It worked and he was able to build little models that ran around the table. The third model he built is preserved in Dublin, and is the first four-wheel locomotive. It is a very different concept from Cugnot’s tractor. The boiler acts as the main frame, with the single, vertical steam cylinder let into the top. The drive is taken via a cross head above the piston head, via connecting rods to cranks on the outside of one pair of wheels. There is no means of steering. It is the first such engine that looks recognisable as any type of steam locomotive. Trevithick, however, was not the only one thinking along these lines and considering ways of designing steam carriages.
William Murdoch was Boulton & Watt’s representative in Cornwall, overseeing the construction and operation of their mine engines. He began his experiments in the 1780s, and one of his fellow engineers, Thomas Wilson, wrote to Watt on the subject on 7 March 1784:
‘He has mentioned to me a new scheme which you may be assured he is very intent upon, but which he is afraid of mentioning to you