An Encyclopedia of the History of Technology part 63 doc

PART THREE: TRANSPORT 602 Australia. Its 386km (240 mile) route was built during 1964–72 to carry iron ore from mine to port, and over it ore is carried in mile-long trains of up to 210 wagons. Average net trainload during 1982–3 was about 17,650 tonnes. The heaviest regular train-load in Britain is small by comparison, but still no mean figure: 3350 tonnes of limestone carried in 43 wagons. Bulk freight operations such as these exemplify the continuing and indeed increasing use of railways in developed countries for specialized functions. Another of these is rapid transit: swift passenger transport within large cities and conurbations. The term embraces traditional underground and tube railways, the upgraded tramway systems of certain cities (mostly on the Continent) which, rather than abandon trams when street congestion made them untenable, put the city-centre sections underground, and recently-built systems combining the best features of both, including reserved-track surface operation where possible. Of these systems there are many, for the principle is as attractive in western countries such as the USA, to reduce traffic jams caused by excessive numbers of private cars, as it is in Communist countries for moving large numbers of carless people. In Britain, the Tyne & Wear Metro, of which the first section was opened in 1980, uses two-car train sets based on continental tramcar design, operated over routes which are partly newly constructed (and much of that in new tunnels beneath central Newcastle upon Tyne) and partly over former British Rail routes. Rapid transit lends itself to automated control of trains, to a greater or lesser degree. As long ago as 1927 the Post Office brought into use its own tube railway, to carry mails beneath London, with automatic operation. The track circuits, instead of operating signals, disconnect current from the section to the rear of each train. This railway, however, carries no passengers. On the Victoria Line, built between 1962 and 1971 and when opened the first new tube railway for passengers in central London for more than 60 years, trains are driven automatically once the train attendant has pressed the start buttons (two of them, because one might be pressed accidentally). On the Bay Area Rapid Transit system (BART) serving San Francisco, a cental computer supervises local automatic control. This 120km (75 mile), 5ft 6in (1.06m) gauge system was built between 1964 and 1974; electricity is supplied by conductor rail at 1000 volts DC. To lure habitual motorists out of their cars, trains run at speeds up to 128kph (80mph) and average 67.5kph (42mph) including stops, approximately twice the average speed of London underground trains. On the Lille Metro, of which the first section was opened in 1983, trains are driven entirely automatically, without any staff on board: television is used to enable the control centre to survey events. Trains run on rubber-tyred wheels, with additional horizontal wheels bearing on guide rails which also act as conductor rails. Rubber-tyred trains have been in use on part of the Paris Metro since 1957; rubber tyres for railway use were developed by the Michelin company during the 1930s. RAIL 603 On London’s Docklands Light Railway, the cost of the complex guidance system needed for rubber-tyred trains was not considered justified, but its 750 volts DC trains are driven entirely automatically. On-train computers control the driving of trains, and are continually monitored by a central computer comparing train positions. The railway was opened in 1987, re-utilizing in part the route and structures of the London & Blackwall Railway of 1840 which pioneered use of the electric telegraph. Between Birmingham Airport, Birmingham International Station and the National Exhibition Centre a 603m (660yd) line uses the maglev (magnetic levitation) system: controlled magnetic fields replace wheels, springs and dampers. The system was developed by British Rail’s Research & Development Division during the 1970s. Vehicles operate singly and are propelled by linear induction motors. NEW HIGH-SPEED LINES The latest systems are diverging increasingly from the traditional railway, with steel flanged wheels running on steel rails. The traditional form has however been used for the two noted systems built new for high-speed long-distance passenger trains: the Japanese Shinkansen and the French Ligne à Grande Vitesse (LGV). By the 1930s the Japanese had developed a dense railway network on the 1.06m (3ft 6in) gauge and were planning a new 1.43m (4ft 8 1/2in) gauge line to relieve the most heavily used route between Tokyo and Osaka. This was eventually constructed by Japanese National Railways as the Tokaido Shinkansen line: much of it was built on viaducts or through tunnels to achieve an alignment suitable for service speeds up to 209kph (130mph). The line had a route length of 515km (320 miles) was electrified at 25kV and opened for regular traffic in 1964. The fastest trains were scheduled to take 3 hours 10 minutes from Tokyo to Osaka, including two intermediate stops. It was not merely the speed of the ‘bullet’ trains which was phenomenal, however, but also the frequency—trains at intervals of fifteen minutes—and the number of passengers. Each train could, and often did, carry 1400 passengers—in a country where only a century earlier the concept of more than one person riding in a vehicle caused surprise, and travel was at walking pace. A network of Shinkansen lines has since been built and by 1988 routes had reached a total of 1859km (1162 miles). Eventually it is intended to extend it through the Seikan Tunnel linking the main island of Honshu with the northern island of Hokkaido. This tunnel—test trains were run through it early in 1988—is at 53.85km (33.5 miles) the world’s longest under-sea tunnel. Its track is laid to 1.06m gauge pending extension of the Shinkansen network. PART THREE: TRANSPORT 604 The French had a comparable problem to the Japanese, excessive traffic on the SNCF’s busiest main line, from Paris to Dijon and Lyon. Absence of a gauge problem, however, meant that expensive construction of new sections and stations within cities could be avoided: standard gauge trains à grande vitesse (TGVs) (see Figure 11.5) depart from the Gare de Lyon in Paris to run over the traditional route for 30km (18 miles) before diverging on to the new LGV line. They regain the old route at the approach to Lyon, or sooner according to their final destination, for TGVs continue over ordinary railways as far afield as Lausanne, Geneva and Toulon. The total route length of new line is 390km (242 miles) it shortens the distance between Paris and Lyon from 512 to 425km, (318 miles to 264) and it is laid out for trains to run at 270kph (168 mph). Construction started in 1976. To minimize environmental disturbance, a strip of land alongside was used for a new long-distance telephone cable, and the route is also paralleled by new roads. Electric traction meant that the ruling gradient could be made as steep as 1 in 28 1/2. Track is laid with rail of approximately 60.3kg/m (122lb/yd) and points are designed so that wheels and flanges are supported continuously and trains can take even the diverging route at speeds as high as 220kph (136mph). The first section was opened in 1981 and the whole line in 1983. The trains themselves consist of eight coaches articulated together plus a power car at each end; two sets can be worked together in multiple. Power car noses are streamlined, their shape established by wind tunnel and computer experiments. The twelve traction motors are spread along the train and, to minimize weight directly on the bogies, are slung beneath coach bodies, with sliding propeller-shaft transmission. The trains operate on 25kV 50Hz AC on Figure 11.5: French Train à Grande Vitesse runs at speeds up to 270km/hr (168mph) on the high speed line built between 1976 and 1983 to link Paris with Lyon and south-east France. French Railways—Vignal. RAIL 605 the new line to produce 6450kW (8650hp); on old lines they operate at reduced power on 1500v. DC. Some are equipped also to operate additionally on 15kV 16 2/3Hz AC so that they can run over the Swiss Federal Railways to Lausanne. On the LGV, cab signalling indicates maximum permitted speed, above which the brakes are applied automatically, and trains are in radio contact with the control office in Paris. On 26 February 1981, during pre- opening trial runs, one of these trains reached 380kph (236 mph). A northward extension of the service occurred in 1984 with the establishment of a through TGV service between Lyon and Lille, using the Ceinture line around Paris to run without booked stops between Lyon and Longeau (Amiens). The same year purpose-built TGVs went into service carrying mails previously conveyed by air. A second LGV in the form of a ‘Y’ from Paris to Le Mans and Tours is under construction and the SNCF envisage one from Paris to Lille, where it would split into lines to Brussels, north Germany, Amsterdam, and London through the Channel Tunnel, for construction of which Anglo-French agreement was reached in 1985. SURVIVING STEAM While specialized roles have been evolving for railways in developed countries, railways elsewhere—in Asia, Africa, South America for instance—have continued to play their traditional role as general carriers. New railways have been built in places as far apart as East Africa, where the 1850km (1150 mile) Tanzania-Zambia Railway was opened in 1975, and western Canada, where the British Columbia Railway’s route length was extended from 696km (433 miles) to 2845km (1768 miles) during the 1960s and 1970s. The most remarkable example, however, is China. There, according to G. Sowler writing in the Newsletter of the Friends of the National Railway Museum (May 1985), there were in 1949, at the end of twelve years of war and civil war, a mere 11,000km (7000 miles) of railways in usable condition. By 1980 rebuilding and much new construction had produced a system of 53,000km (33,000 miles). The first railway bridge across the Yangtse River, across which railways in the north had previously been linked only by train ferry with those in the south, was completed in 1956. China is one of the few countries still to use steam locomotives to any great extent, and the only one in which they have continued to be built in any quantity. In the early 1980s the locomotive works at Datong, established only in the 1950s, was producing 250 to 300 new steam locomotives a year. Most of these were QJ or ‘March Forward’ class 2–10–2s. The other two countries still using large numbers of steam locomotives in everyday service are India and South Africa. South Africa Transport Services’ Rail Network had in 1983 a total of 1647 steam locomotives, which may be compared with 2056 electric PART THREE: TRANSPORT 606 locomotives, 1549 diesel, and 1375 motor coaches for electric multiple unit trains. Experiments to improve steam locomotive efficiency have continued, including equipping locomotives to burn coal on the gas producer system. With this system, which originated in Argentina, a minimal amount of air, mixed with steam, is admitted below the grate and combines with the coal to make gases which are then burned efficiently in air admitted through vents in the firebox sides above the grate. RAILWAY PRESERVATION In Western Europe, North America and Australasia active steam locomotives continue to be things of the present, rather than the past, because of the widespread growth of railway preservation in these areas. During the nineteenth century and the early part of the twentieth, historic locomotives and rolling stock at the end of their working lives were occasionally preserved, by railway administrations and museums, instead of being cut up. In 1927 the Stephenson Locomotive Society, a voluntary body, purchased the 0–4–2 Gladstone for preservation on withdrawal by the Southern Railway, and in 1938 the LNER brought out Great Northern Railway 4–2–2 no. 1, preserved since withdrawal over 30 years earlier, and ran her in steam with contemporary coaches, largely as a publicity stunt to publicize, by comparison, the advances made with the latest streamlined expresses. After the Second World War, Ellis D. Atwood rescued locomotives, track and equipment from closed two-foot gauge railways in the state of Maine, USA, and used them to build and operate the 8.8km (5 1/2 mile) Edaville Railroad round his cranberry farm. In 1950 when the Talyllyn Railway was about to close, the Talyllyn Railway Preservation Society was formed to preserve and operate it (much of the equipment was then some 80 years old) on a voluntary basis. Subsequently the Festiniog Railway Society was formed to revive the Festiniog Railway, closed since 1946 but not dismantled: in 1954, Alan Pegler bought a controlling shareholding in the railway company (later he gave this to charitable trust) and, with voluntary support from the society, the railway was reopened by stages between 1955 and 1982. Meanwhile, in 1963, Pegler had purchased privately the famous Gresley Pacific locomotive Flying Scotman on withdrawal by British Railways, with an agreement to run her over BR tracks. From these beginnings, steam railway preservation has spread far and wide, from California to New Zealand. Steam railways, steam excursions over ordinary railways, and railway museums have become popular and important tourist attractions. Running them has become a widespread and absorbing activity for volunteers and professionals alike. The skills and the equipment needed to maintain and operate steam railways, which would otherwise have RAIL 607 been lost, have survived. Working replicas of important early locomotives have been built. It is appropriate that Britain, which gave steam railways to the world between 1830 and 1870 but later lost its lead in the progress of railway technology, should a century later have given the world the concept of voluntary railway preservation. It is a happy paradox that, in summer during the late 1980s, the only through train service that allowed a day visit from London to the best-known British inland tourist resort, Stratford-upon-Avon, was the Sunday luncheon steam excursion; and the only public transport at all on Sundays between Fort William and Mallaig was the steam train. GLOSSARY Adhesion frictional grip of driving wheel upon rail Bogie short-wheelbase four- or six-wheeled pivoted truck supporting end of locomotive, carriage or wagon Rail, double-headed rail in which, in cross-section, a vertical web links bulbous upper and lower heads of equal size Rail, bullhead rail similar to double-headed (q.v.) but with the upper head larger than the lower Rail, flat-bottom rail of inverted ‘T’ cross-section with a bulbous upper head Rail, fish-bellied rail of cast or malleable iron with lower edge convex for strength, between points of support; so-called from its appearance Skew bridge bridge with line of arch not at right-angle to abutment Tank locomotive steam locomotive in which supplies of water and, usually, fuel are carried upon the locomotive itself instead of in a separate tender Torque converter transmission comprising centrifugal pump in circuit with turbine, or similar device to give infinitely variable gear ratios Valve gear, gab Steam engine valve gear in which each eccentric rod terminates in a ‘V’-shaped gab, set at right angles to it to engage a pin on the valve rod, The appropriate rods are engaged and disengaged for forwards or reverse running Valve gear, link motion steam engine valve gear in which the ends of the eccentric rods for each cylinder are attached to a link, sliding about a die block connected to the valve rod. As well as selection of forward or reverse running, this enables the point in the piston stroke at which steam is cut off from entering the cylinder to be varied, so that economies can be made in steam consumption SOME BRITISH RAILWAY TERMS WITH THEIR NORTH AMERICAN EQUIVALENTS British North American Bogie Truck Chimney Smokestack Coupling Coupler PART THREE: TRANSPORT 608 Engine driver Engineer Fireman Stoker Footplate Deck Guard Conductor Petrol-electric Gas-electric Railway Railroad Shunting Switching Sleeper Tie Tram Streetcar Wagon Car ACKNOWLEDGEMENT I am most grateful to Saelao Aoki and the staff of the Seimeikai Foundation, Tokyo, and to Caroline McCarthy of French Railways, London for their assistance in providing information for this chapter. FURTHER READING Ahrons, E.L. The British steam railway locomotive 1825–1925 (The Locomotive Publishing Co. Ltd., 1927) Allen, G.F. (Ed.), Jane’s world railways (Jane’s Publishing Co. Ltd., London annual publication) Bruce, A.W. The steam locomotive in America (W.W.Norton & Co. Inc., New York, 1952) Ellis, C.H.E. British railway history, vol. I (1830–1876) 1954, vol. II (1877–1947) (George Allen & Unwin Ltd., London, 1959) Haut, F.J.G. The history of the electric locomotive (George Allen & Unwin Ltd., London, 1969) Lewis, M.J.T. Early wooden railways (Routledge & Kegan Paul, London, Ltd., 1970) Nock, O.S. et al. (Eds.) Encyclopaedia of railways (Octopus, London, 1977) Ransom, P.J.G. The archaeology of railways (World’s Work Ltd., Tadworth, 1981) Ransome-Wallis, P. et al. (Eds.) The concise encyclopaedia of world railway locomotives, (Hutchinson, London, 1959) Reck, F.M. On time—the history of the electro-motive division of General Motors Corporation (General Motors Corporation, La Grange (Illinois), 1948) Snell, J.B. Early railways (Weidenfeld & Nicolson, London, 1963). Covers period down to 1914, worldwide Stover, J.F. American railroads (University of Chicago Press, Chicago, 1961) Whitehouse, P.B., Snell, J.B., and Hollingsworth, J.B. Steam for pleasure (Routledge & Kegan Paul, London, 1978). World guide to surviving steam railway operations 609 12 AERONAUTICS J.A.BAGLEY EARLY ATTEMPTS AT FLIGHT Man first tried to fly by imitating the birds, and a large number of individuals strapped themselves to artificial wings, often covered with feathers. Those who attempted to elevate themselves from ground level by vigorous flapping invariably failed; those who launched themselves from the tops of towers usually fell more or less vertically, but occasionally managed to glide a short distance before hitting the ground, often catastrophically. The history of aviation up to the late eighteenth century is littered with these pioneers, and with optimistic attempts to build artificial birds, powered by clockwork springs or gunpowder; otherwise it consists largely of theoretical speculations founded on totally inadequate premises. Although fascinating from many points of view, these activities contributed nothing to later technology. BALLOONS Man first successfully became airborne in the last quarter of the eighteenth century, suspended beneath a large fabric bag filled with heated air. Although there is no apparent reason why this technology should not have appeared centuries earlier—and there are indeed strong hints that it may have done so in the pre-Columbian civilizations of South America—it is a matter of historical record that the brothers Etienne and Joseph Montgolfier initiated the development of balloons with their experiments in 1782–3 at Annonay in France. The Montgolfiers were sons of a fairly prosperous paper manufacturer, and Joseph was a somewhat dilettante student of the physical sciences. His activities were clearly inspired by the publication of Joseph Black’s account of the discovery of gases lighter than common air; Montgolfier conceived the idea that the smoke rising from a fire must contain a gas with this characteristic, and that it should be PART THREE: TRANSPORT 610 possible to contain enough of this gas in a fabric bag to enable the bag to rise. His successful public demonstration of the principle on 5 June 1783 with a spherical hot-air ballon of about 10m (33ft) diameter, which rose to a height of about 2000m (6500ft) and landed 10 minutes later 2km (1.25 miles) away, had a seminal importance out of all proportion to its modest achievement. When the news of this demonstration reached Paris, the scientific community there, better acquainted than Joseph Montgolfier with the current state of scientific research into the properties of gases, assumed that Montgolfier’s gas was Cavendish’s ‘inflammable air’ (later named hydrogen). This could most conveniently be made by pouring sulphuric acid on to iron filings, and Jacques Alexandre César Charles set out to repeat Montgolfier’s experiment using hydrogen. Joseph Black had already attempted to demonstrate this on a small scale, but had failed to find a suitably impervious fabric to contain hydrogen; Charles successfully used fine silk coated with a solution of rubber (which is reputed to have been based on a secret process for manufacturing contraceptive sheaths for the French Court). Charles was also successful in making hydrogen gas on an unprecedented scale to inflate his 3m (10ft) diameter balloon for a public demonstration in Paris on 27 August 1783. The balloon was liberated in the presence of a great crowd and rapidly disappeared into the clouds. Three-quarters of an hour later it landed in the main street of Gonesse, a small village some 20km (12.5 miles) from Paris, whose frightened population attacked the strange monster with pitchforks. It expired with a frightful hissing and a poisonous stench which convinced the peasants of its infernal origins. These demonstrations of model balloons led very quickly to manned flights—the Montgolfiers narrowly won the race when their hot-air balloon carried Pilâtre de Rozier and the Marquis d’Arlandes across Paris on 21 November 1783. On 1 December, Charles and Marie Noel Robert (one of the two Robert brothers who constructed the balloon) flew for two hours in a hydrogen-filled balloon. They landed 45km (28 miles) from Paris, and Charles then took off again by himself, ascending to about 3000 (9800ft) where he suffered a sudden sharp pain in the right ear—now a common affliction of airline passengers in a rapidly-climbing aircraft. These spectacular achievements led immediately and directly to a sudden surge of enthusiasm for ballooning in France, followed quickly in the rest of Europe; this proved however to be surprisingly short-lived and ballooning virtually ceased in Europe for several years. Technically, Charles’s hydrogen balloon was almost perfect, and there was little further development in manufacture or operation for almost a hundred years. Its silk fabric, coated with a varnish of rubber dissolved in turpentine, was sufficiently impervious to hydrogen to permit flights of several hours’ duration. A net of rope meshes covering the top half of the balloon carried a wicker basket for the passengers and a quantity of ballast to be dumped as the AERONAUTICS 611 lifting hydrogen slowly leaked away, or was expanded by the heat of the sun. To release the hydrogen on landing, or to counteract a rising air current, a springloaded flap valve at the top of the envelope was operated by a cord extending down to the basket. The Montgolfiers’ hot-air balloons were much larger—air heated to about 100°C has a lifting capacity of 27kg/100m 3 (17lb/1000ft 3 ), whereas hydrogen provides 96kg/100m 3 (60lb/1000ft 3 )—so they were much more difficult to handle, especially during filling and launch. The idea of a special gas contained in dense smoke was soon found to be erroneous, but Montgolfier’s preference for making a very smoky fire by adding wool, old shoes or more noxious ingredients to his fire to make a denser smoke was well-founded: the particles of greasy soot effectively clogged the pores of the fabric and retained the hot air which was really responsible for lifting his balloons. Hot-air balloons continued to be made and used throughout the nineteenth century, but hydrogen balloons were dominant for 150 years. The only significant technical developments in hydrogen balloons after Charles’s first demonstration were the addition of a ripping panel which could be easily opened by the pilot to facilitate landing in high winds, usually attributed to the American John Wise in 1839; and a trail rope, which was a heavy rope, dropped from the basket so that the end rested on the ground. When the balloon rose, the effective weight of the trail rope increased, so slowing down the rise and stabilizing the flight path. This invention is usually credited to Charles Green (about 1830), but had certainly been proposed earlier, perhaps first by Thomas Baldwin in 1785. The material of the balloon remained unchanged for two centuries—silk was preferred for strength and lightness, but cheaper cotton was often used. The fabric was coated with a suitable varnish, frequently involving a rubber solution. The British army introduced balloons made of gold-beater’s skin in 1883. This material had been used for many years to make model balloons, but as it was available only in pieces up to 1m×0.3m (3ft×1ft), it was not easy to make a fullsize balloon. Gold-beater’s skin is a natural material, derived from the intestines of cattle, and the British army is reputed to have consumed almost the entire output of the Chicago meat-packing industry for several years around 1900. Hydrogen was usually generated by adding sulphuric acid to iron filings and collecting the gas over water in a large-scale version of the school laboratory apparatus. However, for filling military observation balloons during the war against Austria in 1798, the French chemist Charles Coutelle developed a portable furnace in which hydrogen was produced by passing steam over red-hot iron, and variations of this process were often used for generating hydrogen for military balloons thereafter, because the gas produced was acid-free and the apparatus was easier to carry than large quantities of sulphuric acid. . locomotives continue to be things of the present, rather than the past, because of the widespread growth of railway preservation in these areas. During the nineteenth century and the early part of the twentieth,. however, is China. There, according to G. Sowler writing in the Newsletter of the Friends of the National Railway Museum (May 1985), there were in 1949, at the end of twelve years of war and civil war,. use on part of the Paris Metro since 1957; rubber tyres for railway use were developed by the Michelin company during the 1930s. RAIL 603 On London’s Docklands Light Railway, the cost of the complex