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PART THREE: TRANSPORT 472 broad steel wheels by ingeniously linked boards pivoted from their peripheries, but the real answer to the problem of moving across soft ground was the caterpillar track. As early as 1770 Richard Edgeworth patented ‘a portable railway or artificial road, to move along with any carriage to which it is applied’. Sir George Cayley also, in 1825, took out a patent for ‘an endless chain formed of jointed links which fold themselves round the periphery of two wheels’. These patents were, perhaps, in advance of their time and it was not until the early twentieth century that tracked vehicles moved out of the experimental stage. In America, Benjamin Holt of the Holt Tractor Company of California started commercial production of tracked steam-powered tractors in 1904. This firm later became the Caterpillar Tractor Company. In England, Ruston Hornsby developed the patent of David Roberts for tracks of separate links joined by lubricated pins. A tractor thus shod was demonstrated to officials of the War Office in 1907 but, largely due to the indifference of that authority, Rustons sold their patents to Holt. Tracked vehicles were used as artillery tractors first but it was not until 1916 that Winston Churchill, then First Lord of the Admiralty, ordered the first batch of ‘landships’, better known by their code name ‘tanks’, which replaced the earlier ‘water carriers’. They were not an immediate success but later came to be an important military weapon (see p. 993ff.). After the war the use of tracks became common in earth-moving machines, while the internal combustion engine became the standard power unit. Wire ropes and pulleys are still used for raising and lowering long booms such as are used in drag-line and bucket-wheel excavators. However, for relatively short lifts, as in scraper, grader and bulldozer blades or the buckets of dump trucks, front-end loaders and back-hoes, hydraulic systems have largely superseded rope drive. The first application was by La Plante Choate on the Caterpillar Angledozer about 1935 and then on the same company’s scrapers. John Allen, Whitlock and J.C.Bamford in Britain were not far behind. This use of hydraulics came about largely through the development in the 1930s of nitrile rubbers. Their compatibility with mineral oils allowed the use of the latter in place of water, which had previously been used as the hydraulic medium, with its attendant problems of corrosion and excessive seal wear in the cylinders. There being relative motion between the main structure and the blade or bucket of the machine, flexible hoses were necessary, to which the new material was admirably suited. Working pressures have gradually increased so that, today 210kg/cm 2 (3000psi) is considered low and pressures of 350kg/cm 2 (5000psi) are by no means uncommon in mobile equipment. Many other types of specialized machinery are used in road-building and surfacing. The steam-roller has been replaced by the diesel-engined road roller while surfaces of tarmac can now be torn up by a single machine that burns the old tar off the aggregate and returns the latter for re-use. Similar ROADS, BRIDGES AND VEHICLES 473 developments have taken place in equipment for mixing and laying concrete as well as in ripping it or breaking it up when it has passed beyond its useful life. FURTHER READING Bird, A. The history of carriages (Longman, London, 1969) Caunter, C.F. Cycles. History and development. Part one (Her Majesty’s Stationery Office for the Science Museum, 1955) —— Motor cycles—a technical history (Her Majesty’s Stationery Office for the Science Museum, 1982) Charlesworth, G. A history of British motorways (Thomas Telford, London, 1976) Damase, J. Carriages (Weidenfeld & Nicolson, London, 1968) Georgano, G.N. (Ed.) The complete encyclopaedia of motor cars 1855–1982 (Ebury Press, London, 1982) Institute of Mechanical Engineers, Engineering heritage, volume I—the automobile over 75 years (1963) Johnson, E.H.K. The dawn of motoring (Mercedes-Benz UK Ltd, 1986) Pannell, J.P.M. An illustrated history of civil engineering (Thames & Hudson, London, 1964) Smith, D.J. Discovering horse-drawn carriages (Shire Publications, Princes Risborough, 1980) Steinmann, D.B. and Watson, S.R. Bridges and their builders (Dover, 1957) Stephens, J.H. The Guinness book of structures (Guinness Superlatives, London, 1976) Tarr, L. The history of carriages, translated by Elisabeth Hoch (Vision Press, London, 1969 and Corvina Press, Budapest, 1969) West, G. Innovation and the rise of the tunnelling industry (Cambridge University Press, Cambridge, 1988) 474 9 INLAND WATERWAYS JOHN BOYES Water creates both a barrier and a means of communication. The origins of man’s realization that the barrier could be transformed into a means of communication for transport of both men and materials on inland lakes and rivers are lost in the mists of antiquity; unquestionably the concept of using a river’s current for this purpose must have arisen independently in many parts of the world. The sight of a log floating down a stream would soon have inspired an observer to develop the idea. Inflated skins, rafts, hollowed-out trees and fabricated rudimentary boats, the use of poles, oars and primitive sails all had to be tried. But centuries of trial and error, success and failure must have passed before the sophisticated navigational systems of the pre- Roman era gave rise to the pictorial and documentary sources that provide the contemporary information from that period. It was from those formative beginnings using the existing unimproved rivers that the complex integrated waterway networks of the last three hundred years have evolved. THE ANCIENT WORLD The presence of rivers in ancient civilizations, such as the Tigris and Euphrates in Arabia, the Nile in Egypt, the Ganges in India and the Yellow River (Huang He) in China, led to the development of appropriate vessels which provided the means for the generation of trade in a linear direction between riparian towns and communities or between similar settlements on the banks of a lake. Basic civil engineering work within the competence of the locality would have been undertaken to improve the efficiency of navigation, but the great breakthrough came when it was realized that artificial channels on a grander scale than irrigation canals could be dug to link rivers together, to take navigable water across watersheds between one river basin and another and to provide water communication to places remote from the natural river courses. INLAND WATERWAYS 475 In pre-Roman times canals to by-pass the cataracts of the Nile had been built by about 2000 BC. Cargo handling facilities were provided to load and unload monoliths such as the massive obelisks erected in Egypt. The most famous waterway project of the classical world, the Corinth Canal, was not to be realized until modern times. It seems that China had one of the earliest, if not the earliest, true navigational canals (though it was probably conceived as an irrigation channel) in the Hung Kou Canal, later known as the Pien Canal. It was possibly built in the time of Confucius in the late sixth or early fifth century BC and linked the Yellow and Huai rivers. Though running through fairly flat country it was some 418km (260 miles) long. About 215 BC it was necessary to provide a freight canal, initially for war materials, across mountainous country to link tributaries of the Yangtse, the Hsiang flowing north and the Li flowing south, with the western rivers in south-east China. This was the Ling Chhu or Magic Canal and its importance lies in the fact that it was the earliest contour transport canal, winding round the mountainside for about 32km (20 miles). In order to maintain the levels techniques were used which were not developed elsewhere in the world until centuries later—the construction of massive embankments and dressed stone retaining walls. About AD 600 an improved and extended canal was built on a new alignment but roughly parallel in part to the old Hung Kou and this steadily developed with its branches into what became known as the Grand Canal with a total length of nearly 1770km (1110 miles) from Tianjin to Hangzhow. It included a fairly low summit level of 42m (138ft) above sea level. It was intensively used and it is recorded that in 838 a train of 40 boats, many lashed two or three side by side, was drawn by two water buffaloes. Periods of decay and siltation were followed by improvements, for example through the Yangtse gorges, and it is still in use. There is good evidence that the Chinese developed an early form of pound lock—a chamber the length of a boat with gates at each end so that boats could be raised or lowered in the chamber by the operation of sluices. Although such developments had taken place over many centuries from earliest times there was a long interval in the mediaeval period before a fresh wave of innovation heralded the genesis of a new waterway age more or less simultaneously in many countries. THE BRITISH ISLES The long tradition of waterway transport, and indeed the use of rivers for other purposes, has been of fundamental importance in the economic development of Britain. Most, if not all, rivers of any size have been used in part for transport for millennia but it was the Romans who seem to have PART THREE: TRANSPORT 476 brought engineering skills to improve the natural watercourses or to dig new lengths to serve their military needs. Just how far they extended in this field is a matter of archaeological debate. Certainly they were responsible for the earliest canal still in use in England today—the Fossdyke Navigation in Lincolnshire providing a connection between the Trent at Torksey and the Witham at Lincoln. Less certain is whether the Caerdyke from Cambridgeshire into Lincolnshire was solely a drainage channel or a navigation and that again is a source of debate. In the Dark Ages, between 400 and 1000, there is virtually no evidence of waterway improvement: one of the few references to the use of rivers is the stranding of the Danish fleet in the Lea probably north of Waltham Abbey by the excavation of additional channels in the tenth century. It is also the Lea which provides an early documentary reference to river improvement in an order issued in 1190 authorizing the Abbot of Waltham, in what is now Essex, ‘to turn aside the course of the water of the Lea in…Waltham as he wishes without harming anyone and for the advantage of navigation’. The Lea again illustrates the importance of river transport in mediaeval times when an Act of Parliament was passed in 1424 establishing a commission to deal with the problem of shoals in the bed of the river which were impeding the navigation. This was the first time an Act had been passed to improve a single river. The first true canal to be built in England since the Romans was a short one designed to facilitate the passage of small sea-going vessels to Exeter opened in 1566. Lock gates were installed and although mitre gates are shown in a drawing of 1630 there is no certainty that they were originally used. The Exeter Canal was further enlarged and improved from 1698 to 1701. Although the Exeter Canal had a pound lock separating the non-tidal canal from the tidal range of the sea the first pound lock to be built on an English inland navigation was not constructed until 1577. This was at Waltham Abbey, on one of the several channels of the Lea, and was 70ft by 22ft (21.3×6.7m). Owing to local disputes and general decay it survived only until 1592. Elsewhere on the rivers the differences in levels were overcome by flashlocks— contrivances which penned back the water; when boats required a passage downstream the stakes forming the pen would be removed and the resulting cascade of water carried the boats downstream and over the shallows below the lock. Boats working upstream had to be winched through as the fall slackened and then the vertical stakes would be replaced to pen back the upper level again. Such flash locks existed until the beginning of the present century on the Thames and other rivers. The seventeenth century saw the growth of progressively articulate opinion on the value of river improvement and authority for some engineering work was obtained. By the end of the Commonwealth (1660) there were some 1100km (685 miles) of river navigation which rose to 1870km (1160 miles) in the next half-century with improvements on, for example, the Great Ouse from INLAND WATERWAYS 477 Bedford, the Thames, the Mersey and Irwell and the Aire and Calder, while others were actively being canvassed. It was in the eighteenth century that the real waterway network expansion occurred, spurred on by growing industrial enterprise. At the beginning of the century the Suffolk Stour received its Act in 1706. A Board of Trustees for the Lea was established in 1739, following disputes between the bargemen and the New River Company established to supply water to London from springs in the Lea valley and who were augmenting their supply from the river itself. Soon after this came the first true canal to be built in the British Isles since the Exeter Canal—the Newry Canal of 1742 linking Newry with Lough Neagh in Northern Ireland. Proposals had been made at the end of the previous century but no action had then been taken. Now it was built, 29km (18 miles) long with 14 locks, and foreshadowed the building of many canals independent of river navigations. The engineer was William Steers, who had also engineered the Mersey and Irwell Navigation and had built docks in Liverpool. His pupil, Henry Berry, built the first modern canal in England, the St Helens Canal, opened in 1757. In 1759 the Duke of Bridgewater, who had been on the European Grand Tour and had seen canals on the Continent, obtained an Act to build a canal from his pits at Worsley to carry coal to Manchester. He was fortunate in obtaining the services of James Brindley, a millwright who had great natural engineering ability, who was engaged to re-survey and build the canal. Following a second Act the canal was completed to Manchester in 1761, crossing the Irwell on an aqueduct. This was the first British boat aqueduct and Brindley’s massive masonry structure of three arches to carry the canal survived until the construction of the Manchester Ship Canal, opened in 1894, when the original aqueduct was replaced by a swinging aqueduct which remains unique. The face of one of Brindley’s arches has been re-erected by the side of the road leading from Barton to Eccles. The fame of the Bridgewater Canal is that at the Worsley end the canal continued underground to the coal faces in the pits and at one time there were some 74km (46 miles) of waterways underground on three levels linked by inclined planes allowing the boats to be transferred between levels. The boats were taken virtually to the coal face where the coal was loaded into demountable containers. When full the boats were propelled manually to the open air at Worsley basin where they were assembled into gangs of two or three and towed to Manchester. The full containers were then removed and replaced by empty ones for the return journey to Worsley—a very early example of containerization. The underground ceased operation in 1887. The immediate success of the Bridgewater Canal stimulated a fever to construct other canals and Brindley’s genius was in demand. He was the engineer for the Trent and Mersey, the Staffordshire and Worcestershire, the Coventry, the Oxford and the Birmingham Canals, and as all these were under PART THREE: TRANSPORT 478 construction at more or less the same time supervision had to be delegated. Brindley died in 1772, the year in which the 128km (76 miles) Staffordshire and Worcestershire was completed linking his Trent and Mersey Canal at Great Heywood with the river Severn at Stourport and with the Birmingham system at Aldersley. The Trent and Mersey, 150km (93.5 miles) was not completed until 1777, but Brindley’s standards left their mark on the dimensions of the Midland canal system as we know it today. Among his major works were the Hare-castle tunnel on the Trent and Mersey which took eleven years to build (Telford completed a second tunnel in two years in 1827); and the Trent aqueduct near Great Heywood carrying the Staffordshire and Worcestershire across the Trent. Brindley’s efforts were the stimulus for industrialists and others elsewhere in the country to embark on new undertakings or to improve further the existing navigations. The national system had grown slowly from the figure of 1866km (1160 miles) in 1720 to 2250km (1400 miles) in 1760, but by 1780 it had reached over 3200km and was to exceed 4800km (3000 miles) in 1800. It took another 50 years to reach its maximum extent of just over 6437km (4000 miles) before the non-economic waterways started to close down in the face of railway competition and railway purchase. Included in these developments were the Brindley-surveyed Coventry and Oxford Canals which were to provide the first link of the Midland system with London. Brindley had adopted the contour system of construction so that his canals looped tortuously round hills and valleys, particularly on the Oxford Canal. Nevertheless the four great rivers, the Trent, Severn, Mersey and Thames were linked by 1790. Meanwhile, further north, a new canal and to much greater dimensions than Brindley had favoured was projected with John Smeaton as engineer—the Forth and Clyde Canal. It had been considered in the Restoration period and a further survey was made in 1726 but it was after William Pitt (later Earl of Chatham) suggested a canal built at public expense that Smeaton made his survey in 1764. He later revised his survey and in 1768 the Act was passed. Work started soon after, but by 1778 funds which had been privately subscribed, contrary to Pitt’s view, were running low and the government in 1784 agreed to lend £50,000. The canal was completed in 1790, Smeaton having resigned in 1773. This was one of the canals where a regular passenger service operated. It started in 1809, included a night service from 1824, and ceased about 1848. Another major east-west link proposed in the 1760s was the Leeds and Liverpool Canal. Surveyed by John Longbotham, it was controlled by two committees, one in Liverpool and the other in Bradford. Brindley was asked to arbitrate over the line which should be taken in Lancashire and later he was appointed chief engineer but withdrew. Longbotham was then appointed engineer. It received its Act in 1770 and by 1774 the famous five-rise staircase at INLAND WATERWAYS 479 Bingley was completed, remaining today one of the visual attractions of British waterways. The second major engineering work was the Foulridge tunnel under the Pennines at summit level, completed in 1796; while the third great feature was the 1.2km (0.75 mile) embankment across the Calder valley at Burnley completed in 1799. However the full 204km (127 miles) canal was not completed until 1816–46 years after it was started—because of the work involved in the 23-lock flight at Wigan. The problems arising from the meandering course of the Oxford Canal and the increasing traffic between Birmingham and London necessitated a more direct line. In 1791–2 a line was surveyed from Brentford on the Thames to Braunston near Rugby on the Oxford Canal for 70 tonne boats. William Praed was chairman and William Jessop engineer. Work started as soon as the Act was obtained in 1793 and this involved the construction of two tunnels. Braunston tunnel was opened in 1796, but difficulties occurred at Blisworth because of flooding. Apart from the tunnel, the canal was complete by 1800 so goods were transported by a horse tramway over Blisworth Hill until the tunnel was completed in 1805. Another problem was the crossing of the Ouse at Wolverton where boats at first locked down to river level and then up again on the other side. This system was replaced in 1805 by an aqueduct which collapsed in 1808. Replaced by an iron aqueduct, it reopened in 1811. Traffic soon became extremely heavy. Known as the Grand Junction Canal it acquired smaller canals including both the Old Grand Union Canal and the Leicestershire and Northamptonshire Canal which met at a flight of ten locks forming a bottleneck at Foxton. In 1900 the Grand Junction’s owners decided to overcome this problem by constructing an inclined plane carrying two tanks or caissons tranversely on the slope. The tanks were hauled by cables, the haulage power being provided by a stationary steam engine to the top of the plane, but the cost of maintaining the boiler and engine in steam rendered it uneconomic and by 1917 it had been taken out of use. Following the completion of the Grand Junction to Paddington basin in London, a canal was promoted to link west London with east London and the lower Thames. This was completed in 1820 as the Regents Canal and terminated in a dock at the eastern end with a lock into the Thames. Over the years this dock was enlarged. The last length of canal to be built in the south of England was opened on 1 April 1968 as a link between the Limehouse Cut of the Lee Navigation and the dock to enable the Lee traffic to enter the Thames via the Regents Canal Dock lock and so to abandon the old and difficult Limehouse Cut Lock. (Although the waterway is in the Lea valley and in part was and is the River Lea its legal title is the Lee Navigation.) On 1 January 1929, after some years of negotiations, the Grand Junction amalgamated with three canals in Warwickshire and the Regents Canal to form the Grand Union. The Warwick and Birmingham and the Warwick and Napton were both built as part of the improved line between London and PART THREE: TRANSPORT 480 Birmingham, and the Birmingham and Warwick Junction was added in 1844 to cope with the increased traffic. Although the Severn was connected to the ‘national’ network of canals it was a treacherous river to navigate in its lower reaches, so in 1792 a proposal was made to construct a ship canal for 300 tonne vessels from Gloucester to Berkeley Pill. An Act was obtained in 1793. Work started the following year but by 1800 only 29km (5.5 miles) had been built. Work ceased for want of money until 1819 and again in 1820–3. It was then restarted and the 26.5km (16.5 miles) were finally completed in 1827 and capable of taking 600 tonne vessels. Instead of continuing south to Berkeley Pill, the canal terminated at Sharpness Point where a much larger harbour and entrance lock were opened in 1874. The Gloucester and Sharpness Canal Company also constructed extensive docks at Gloucester. Later, by leasing the Worcester and Birmingham Canal, the company obtained a through-water route to Birmingham. An east-west link in southern England had been canvassed since the sixteenth century, but it was not until 1794 that an Act was passed to link the Kennet at Newbury with the Avon at Bath. The Kennet and Avon Canal, completed in 1810, included the Caen Hill flight of 29 locks at Devizes, two notable aqueducts by John Rennie, who was the canal engineer, the Dundas at Limpley Stoke and the Avoncliff, and two interesting pumping stations for supplying water to the canal, one at Claverton powered by a waterwheel and one at Crofton powered by steam. While many smaller canals were constructed, some of which included pioneering structures such as the boat lifts on the Grand Western in Somerset and the inclined planes on the Bude, Chard and Shropshire Coal Canals, the last major canal of the inland canal system was the Birmingham and Liverpool Junction Canal. Becoming in 1846 the Shropshire Union Canal, it ran from Autherley on the Staffordshire and Worcestershire north-westwards to Nantwich on the Ellesmere and Chester Canal. Proposed by Thomas Telford and receiving its Act in 1826, it was completed in 1835. Unlike the Brindley contour canals, it was straight with deep cuttings and high embankments. The Ellesmere and Chester had incorporated the Ellesmere Canal, under whose 1793 Act the great iron aqueduct with masonry piers was later built across the Dee at Pontcysyllte and opened in 1805. Also on this line was the Chirk aqueduct across the Ceiriog. In the north of Scotland the Great Glen forms a natural line of fairly lowlying country relative to the high lands on each side and as early as 1726 the line was viewed as a possible ship canal route from coast to coast. It was again surveyed in 1773–4, in 1793, and by Telford in 1801–2. Wartime considerations demonstrated the advisibility of such a link, as it would enable vessels to avoid the attentions of French privateers and also provide a safer passage than the rigours of the Pentland Firth. Acts were passed in 1803 and 1804. Telford was appointed engineer, William Jessop consultant, and the two worked in harmony until the latter’s death in 1814. The canal was a series of cuts linking several INLAND WATERWAYS 481 lochs, including Loch Ness, with locks sometimes in groups as at Neptune’s Staircase, the flight of eight locks at Bonavie, and sometimes singly. It was not completed until 1822 but, although it proved its worth at times it was less valuable as a major ship canal than had been hoped. An earlier, though much shorter, ship canal in Scotland was the Crinan Canal, 14km (9 miles) and 15 locks across the Mull of Kintyre, constructed between 1793 and 1815. In Ireland the Shannon, the longest river in the British Isles, which had always been navigable in parts, began to be improved in the mid-eighteenth century, while at the beginning of the nineteenth century links with Dublin gave it added importance. After a number of abortive starts in the mid- eighteenth century work restarted in the 1770s on the Grand Canal from Dublin and 24km (15 miles) had been opened by 1779. This canal, while designed to reach the Shannon at Shannon Harbour, which it did in 1803, also had the Barrow branch running from near Robertstown southward past Monasterevin to Athy, reaching there in 1790 where it joined the Barrow Navigation. A further branch left westward at Monasterevin for Mountmellick in 1850. The original terminus in Dublin was at St James’s harbour west of the city centre, but with the completion to Athy it was felt that there should be a connection with the river Liffey close to St James’s Harbour. Instead it was built on a semi-circular route round the south of the city to join the Liffey on the east of Dublin. At this point a dock system, the Ringsend Docks, was built by William Jessop, and both the docks and the new line with seven locks were opened on 23 April 1796. An extension beyond the Shannon to Ballinasloe was opened in 1828. The Grand Canal was unusual in that a series of hotels was built alongside the canal for the benefit of passengers travelling by boat. Excellent surviving examples are at Portobello, Dublin, opened in 1807, and Robertstown, opened 1801, though neither still operates as a hotel. A rival canal running from Dublin to a more northerly point on the Shannon was promoted in the 1780s. This was the Royal Canal and work began in 1789 at the Dublin end. It leaves the Liffey on the north bank almost opposite the Ringsend Docks. Construction progress was slow and in 1802 John Rennie was called in to advise but it was not completed to the Shannon at Tarmonberry, 145.5km (90.5 miles) from Dublin, until 1817. It included a very deep cutting to the west of Dublin known as the Deep Sinking and a high embankment over the Ryewater. In 1845 it was bought by the Midland Great Western Railway so that a railway could be built alongside. Over the years traffic declined and it was officially closed in 1961. Towards the end of the nineteenth century the largest of the British canal projects was conceived. Manchester, at the hub of the cotton industry, was suffering because of the Liverpool port charges and the rail monopoly between Liverpool and Manchester. Suggestions were made in 1876 that a ship canal should be built from the Mersey to Manchester and the idea was accepted. Despite the opposition of the authorities in Liverpool and the railway companies, ichemx . barrier and a means of communication. The origins of man’s realization that the barrier could be transformed into a means of communication for transport of both men and materials on inland lakes and rivers. to form the Grand Union. The Warwick and Birmingham and the Warwick and Napton were both built as part of the improved line between London and PART THREE: TRANSPORT 480 Birmingham, and the Birmingham. the Bude, Chard and Shropshire Coal Canals, the last major canal of the inland canal system was the Birmingham and Liverpool Junction Canal. Becoming in 1846 the Shropshire Union Canal, it ran

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