An Encyclopedia of the History of Technology part 58 pot

PART THREE: TRANSPORT 552 blocks placed in the centre of the bottom of the dock. She would then be supported on either side by shores against the dock side, before the dock would be drained by sluices as the tide ebbed. From the eighteenth century onwards, docks began to be lined with brick or stone, and the sides were often stepped to facilitate fixing the shores. Later still, pumping machinery was provided to empty the dock, while instead of gates the entrance was often fitted with a caisson, a floating structure which fitted the entrance closely, but which could be floated to one side or into a special recess to allow entrance or exit of ships. If no dock was available, ships under repair had to be careened, or hove down to a steep angle using special blocks and tackles to the mastheads. In tidal waters, however, gridirons or hards could be used, the ship standing upright, and work being done between tides. The building and maintenance of royal fleets was everywhere entrusted very largely to state dockyards, which, incorporating as they did all the various necessary trades in the one establishment, became the earliest large-scale industrial undertakings, employing more than 1000 men even in the late seventeenth century. The largest warships were so much bigger than any merchant ship as to be beyond the capacity of private shipbuilders, and this was a powerful influence in the rise of dockyards; in addition, the existing ships had to be cared for, an peace as in war, while large stocks of all kinds of stores had to be kept up against the eventuality of hostilities. In many cases, the dockyards embodied the most advanced techniques of their day, such as the early use of stone for docks, large-scale manufacture of rope, and early in the nineteenth century mass-production methods in Marc Isambard Brunel’s block-making machinery (see p. 405); in matters of detail there is ample evidence of careful thought in layout. At Sheerness in the 1820s Rennie had the opportunity of creating a new yard to replace the old ramshackle one. Most of his buildings were iron-framed and fire-proof, there were tunnels to bring masts from the masthouse to the storage ponds and many other sound ideas, including steam pumping engines. Navies had also to provide for their other needs. Naval victualling required the preparation of much preserved food, and this was found, again for reasons of scale, to be best done by the service. So one finds breweries, bakeries and slaughterhouses and meat preservation and packing houses under naval control, together with storehouses. Guns, ammunition and powder were often provided by other government establishments, in co-operation with the army, while naval hospitals were early examples of large-scale care for the sick. In the nineteenth century all shipbuilding establishments changed dramatically, as, in many cases, did their geographical locations. Steam engines, iron ships and larger ships called for great extensions to dockyards and reorganization of private yards, with foundries, plate shops, machine shops, steam hammers and all the equipment for handling iron and later steel. PORTS AND SHIPPING 553 An important additional trade, usually by specialist firms, was the production of armour plate. Although the size of merchant ships increased to become comparable to that of warships, the state dockyards continued to build some of the ships required for navies, although the proportion was smaller than in days of wood and sail, and they also added submarines to their range. DIVING Men have used various devices to work or remain under water since Greek divers destroyed a boom during the siege of Syracuse in 415 BC although in no case could they stay down very long. Such means were simply to hold one’s breath or to have an air bag or a crude helmet, or even an air pipe from a bladder on the surface. By the sixteenth century the diving bell, where pressure keeps out the sea water, enabled wrecks to be examined and even some salvage work such as that of Phips in the Bahamas in 1687. In the eighteenth century, air was piped down to diving bells, while diving suits were used by Lethbridge and Freminet, and Borelli pumped air down to his suit. These improvements permitted work to be done under water to a depth of about 15m (soft), and this was obviously important for harbour works. In 1819, Augustus Siebe patented his ‘open’ diving suit, with pumped air, followed in 1837 by his ‘closed’ suit, the real pioneer of modern diving dress. With its aid, much salvage, survey and construction work became possible. At the same time, however, other possibilities were being explored, such as a diving chamber, one of which reached 74.5m (245ft) in 1865, and a semi-independent suit using compressed air, both being French. In connection with this activity, underwater apparatus of various kinds was developed and information was gathered about the effects of depth and of compressed air and other factors on the divers themselves. Following the First World War, gold was recovered from both the Laurentic and the Egypt in very deep water. Divers on the Egypt descended to 119m (393ft) using steel articulated suits, and this idea was extended to deep diving research craft such as Beebe’s Bathysphere in the 1930s and Piccard’s Bathyscaphe in the 1950s. In the 1920s had come the first moves towards another style, of quite independent diving, with foot fins, goggles, and compressed air carried by the diver, or later helium. During the Second World War Jacques Cousteau perfected his Aqualung along these lines. Together with advances made by the navies of the world, the basis was laid for the great progress in underwater activity since, not only in general exploration and oil-rig working, but in the recovery by the aid of much new equipment of articles from wrecks and the fragments of crashed aircraft, begun with the Comet disaster of 1954. Working under compressed air at great depths can produce bubbles of nitrogen in the bloodstream, inducing compression sickness (‘the bends’) PART THREE: TRANSPORT 554 which can prove fatal. It is averted by bringing divers to the surface at a slow and carefully controlled rate. FURTHER READING For the development of the ship, the several volumes of the British National Maritime Museum series The ship may be recommended. Published by Her Majesty’s Stationery Office for the Museum. For the history of navigation, the best general work is Commander W.E.May, A history of marine navigation (G.T.Foulis, Yeovil, 1973). For lighthouses, see Douglas B.Hague and Rosemary Christie, Lighthouses: their architecture, history and archaeology (Gomer Press, Llandyssul, 1975). For ports, James Bird’s The major seaports of the United Kingdom (Hutchinson, London, 1963) offers many insights. For dockyards, Jonathan Coad’s Historic architecture of the Royal Navy (Gollancz, London, 1982) is invaluable. As a general compendium, Peter Kemp’s Oxford companion to ships and the sea (Oxford University Press, Oxford, 1976) will prove most informative. 555 11 RAIL P.J.G.RANSOM RAILWAYS BEFORE LOCOMOTIVES Rail transport as we know it today is descended from railways used underground in the mines of central Europe in the sixteenth century. These had rails of wood and along them small wagons were pushed by hand. German miners may have introduced the concept to Britain late in that century. The first line in Britain on the surface was completed in 1603–4 by Huntingdon Beaumont: it ran from a coal mine near Wollaton for two miles to a point close to Nottingham where the coal could be sold. A similar line was built in Shropshire the following year, and Beaumont built three more in Northumberland. These were imitated by other coal owners, gradually at first because of the unstable political state of Britain in the seventeenth century, but with increasing frequency during the eighteenth. Some of these wagonways carried coal from pit to point of sale, but far more delivered it to a wharf for onward carriage by barge or ship. Such a layout lent itself to the construction of lines on gentle continuous gradients down which laden wagons ran by force of gravity; horses hauled them empty back uphill. For their period, the engineering of these lines was advanced. The wagons were guided by flanged wheels and braked by brake blocks bearing on the treads (a practice as yet unknown on road vehicles); castiron wheels started to come into use, probably, during the 1730s. The wooden track was well built and carefully maintained, cuttings, embankments and bridges enabled gradients to be easy, and, in Northumberland and Durham, lines terminated at high level on staithes so that coal could be fed by gravity into ships waiting below. The most notable surviving relic of the period is Causey Arch, Co. Durham, the 32m (105ft) stone span of which once carried a wagonway across a ravine. The first wooden railway in the USA was built in 1795, and by 1800 the total length of wooden wagonways in Britain, made up from many short lines, was probably PART THREE: TRANSPORT 556 approaching 480km (300 miles). By then another fundamental development had taken place. To simplify the replacement of worn rails, the practice had grown up of making rails in two parts, one on top of the other, so that only the top part needed to be replaced. In 1767 at Coalbrookdale, Shropshire, hard-wearing cast iron was for the first time substituted for wood as the material from which the top part of the rails was made. Track of this type was installed on the line built to extend the Trent & Mersey Canal’s Caldon branch to limestone quarries at Caldon Low, Staffordshire. Between the end of the canal at Froghall and the quarries lay an ascent of over 200m (670ft) in 5.6km (3.5 miles), practicable for a horse-and-gravity railway but scarcely so for a canal. The whole line was authorized by Act of Parliament in 1776, the railway section being the first to be so authorized. The obvious step forward of making the rails entirely of cast iron seems to have occurred in South Wales, where ironworks were using iron edge rails, deeper than they were wide, in the early 1790s. William Jessop, foremost canal engineer of the day, employed iron rails of T-section in 1793–4 on the Leicester Navigation’s part-rail, part-canal Forest Line. This was during the great period of canal construction in Britain (see Chapter 9), and many short horse railways, and some not so short, were built in connection with canals. The terms tramroad or tramway (the derivation is uncertian) came to be used to describe them. See Figure 11.1 for an illustration of an iron-railed horse railway. The form of track used on most of them, however, proved eventually to be a diversion, a blind alley, from the proper path of progress. Iron rails of L- section were used, in combination with unflanged wheels running loose on their axles; rails were laid with the flanges located along their inner edges, probably so that stones and other obstructions on the running surface could be cleared away easily. Light narrow gauge track of this type had been developed by John Curr for use in coal mines and was first used above ground in 1788; subsequently tramroads, or ‘plateways’, using comparatively heavy L-section rails laid on sleepers made from stone blocks were extensively promoted by Jessop’s associate Benjamin Outram, and came into general use. Only in north- east England, with its long tradition of flanged wheels, were edge rails still used extensively: there, iron first replaced wood as the rail material in 1797. In 1799, Jessop recommended that an iron railway should be substituted throughout the length of a proposed canal for which it appeared, on investigation, that water supplies would be insufficient. The consequence was the Surrey Iron Railway, a plateway opened in 1803 between Wandsworth and Croydon: it was the first public railway independent of canals, that is to say, it was built and run by a company incorporated by Act of Parliament for the purpose, and it was available for use by all comers. During the next four decades many other public horse railways were built; on one of them, the RAIL 557 Oystermouth Railway running westwards out of Swansea, the innovation was made in 1807 of carrying passengers (in a horse-drawn coach)—the first fare- paying passengers carried by rail. Eventually, the routes of horse railways in Britain totalled about 2400km (1500 miles). In the USA, construction of the Baltimore & Ohio Railroad as a horse railway commenced in 1828. Its track was made up of wooden rails with longitudinal wrought-iron straps fastened along them to form the running surface: the first railway of this type in the USA had been completed in 1826. The first public railway in Austria was the horse railway built from Linz to Budweis between 1827 and 1832. Horse railway engineering works included tunnels, viaducts and inclined planes. Self-acting inclined planes had originated on the Continent and were used on British wooden railways from the mid-eighteenth century onwards, in locations where gradients too steep for ordinary horse-and-gravity operation Figure 11.1: A horse railway built in 1815 to carry coal to Belvoir Castle, Leicestershire, from a canal wharf was still in use a century later. Cast-iron fish- belly edge rails can be seen. PART THREE: TRANSPORT 558 were unavoidable. Laden wagons about to descend were connected by a rope, which led round a winding drum at the head of the incline to empty wagons at its foot so that the former, during their descent, could haul the latter up. But where it could not be guaranteed that the weight of descending wagons would regularly exceed that of those ascending, an external source of power was needed. By the end of the eighteenth century, the stationary steam engine had been developed far enough to provide it. One of the earliest such installations was made by the Lancaster Canal Co. in 1803–4. The deep valley of the River Ribble separated two completed sections of the canal, and a tramroad was built to link them which descended by inclined planes into the valley, and crossed the river by a low-level bridge; it was intended as a temporary expedient pending construction of a high-level aqueduct which in fact was never built. The incline at Preston, on the north side of the river, was powered by a steam engine. Cable haulage on inclined planes, both powered and self-acting, then became a common feature of railways built during the ensuing forty years. In some cases gradients were steep, in others not—the Cromford & High Peak Railway, for instance, was built between 1825 and 1831 with inclined planes ranging in gradient between 1 in 7 and 1 in 60. Some railways achieved powered transport over considerable distances by means of successive inclined planes: the preserved Bowes Railway, Tyne & Wear, is of this type. This method of operation was still further developed in north-east England by Benjamin Thompson, who achieved power traction over level or gently undulating lines by positioning stationary engines at intervals. When an engine was drawing a train of wagons towards it by means of the ‘head rope’, there was attached to the rear of the train the ‘tail rope’ from the previous engine, running off an out-of-gear winding drum. When the wagons arrived at the engine, the tail rope was detached to become the head rope for a train in the opposite direction. This system was installed continuously over five miles of the Brunton & Shields Railroad, completed in 1826, where trains were conveyed by rope haulage at overall speeds of nearly 9.6kph (6mph) including stoppages for rope changing. THE FIRST STEAM LOCOMOTIVES By 1826, however, steam locomotives—though not, as yet, particularly efficient ones—were already in commercial service. They had originated with the work of Richard Trevithick who, in about 1797, had conceived the brilliantly simple notion that James Watt’s separate condenser patent for stationary steam engines (see Chapter 5) could be avoided by using steam at a high enough pressure for the exhaust to be led to the atmosphere, so that the condenser could be eliminated altogether. A side-effect of this development was that RAIL 559 boiler and engine could then be made compact enough to become the power plant of a self-propelled vehicle. The first attempt to build a locomotive to Trevithick’s ideas was made by the Coalbrookdale Company in 1802, but little is known about it and it seems unlikely that it worked satisfactorily. It was otherwise with the next locomotive, built under Trevithick’s supervision at Penydarren Ironworks, South Wales. On 20 February 1804, without difficulty, it conveyed 10 tonnes of iron, five wagons and seventy men riding on them for more than 14km (9 miles) along the Penydarren or Merthyr Tramroad, a plateway completed in 1802. Probably this locomotive had a cylindrical boiler with, set into it, a single horizontal cylinder, and cylindrical furnace and return fire tube: and was carried on four wheels driven through gears. Steam was exhausted up the chimney to draw the fire. Unfortunately the track was not substantial enough for a locomotive and too many brittle cast-iron rails were broken: so the locomotive was altered for use as a stationary engine. A similar fate met another Trevithick-type locomotive built at Gateshead the following year which had been intended for Christopher Blackett’s wooden- railed Wylam Wagonway in Northumberland. In 1808, Trevithick demonstrated a locomotive on a circular railway in London; this locomotive had a vertical cylinder and the rear wheels were driven directly by connecting rods. By 1811 the Napoleonic wars had inflated the price of horse fodder so much that J.C.Brandling was considering use of a steam locomotive on his Middleton Railway, an edge railway carrying coal from a colliery into Leeds. John Blenkinsop, who was Brandling’s colliery manager, believed that a locomotive light enough to avoid damaging the track would be too light to haul a useful load by adhesion, so he invented a rack railway in which a pinion on the locomotive would mesh with teeth cast along the side of one of the running rails. The locomotive, designed and built in Leeds by Matthew Murray, was a development of Trevithick’s 1808 locomotive with two vertical cylinders, cranks at right angles and the rack pinion driven through gears. The first of these locomotives came into use in June 1812: it was the first steam locomotive to go into regular service, for it worked well, hauling 30 coal wagons at 4.8kph (3mph), and was soon joined by others. Blackett was prompted to attempt locomotive haulage again. He had already re-laid his wagonway as a plateway; his manager William Hedley carried out experiments, first with a model and then with a full-size test carriage driven by men turning handles, and concluded that a locomotive could work by adhesion alone if its two pairs of wheels were coupled by gears. The first locomotive which was then built at Wylam was a failure, its boiler producing insufficient steam, but the next, completed in the spring of 1814, was a success, except that it damaged the track. To spread the load it was converted to run on two four-wheeled bogies, which it and subsequent similar locomotives at Wylam did until about 1830 when the line was re-laid as an edge railway and the locomotives put back on four wheels. These locomotives PART THREE: TRANSPORT 560 ran until the 1860s and two survived to be preserved, as Puffing Billy and Wylam Dilly in the Science Museum, London, and the Royal Museum of Scotland, Edinburgh, respectively. George Stephenson One of those who came to watch the early trials of the Wylam locomotives was George Stephenson, a self-taught mechanical genius who was at this period chief enginewright at Killingworth colliery near Newcastle upon Tyne. A wagonway with iron edge rails connected the colliery with the river and for this in 1813 Stephenson was instructed by his employer, Sir Thomas Liddell, to build a locomotive. Its design was probably based on the Middleton type of locomotive, but drive was by adhesion, not rack. So when this locomotive, called Blucher, was completed in July 1814 it pioneered what ever since has been the conventional arrangement: it was the first locomotive both to be driven by adhesion, and to have flanged wheels running on edge rails. For the next decade and a half, other engineers seemed to lose interest in locomotives and Stephenson almost alone and step by step introduced improvements—geared drive gave way to wheels coupled by chain, for instance, and eventually to coupling rods. He built more locomotives, and in about 1819 he laid out the Hetton Colliery Railway, from Hetton-le-Hole to Sunderland, as the first railway designed to have no animal traction. Its 13km (8 mile) route included two sections to be worked by locomotives, while the rest comprised powered and self-acting inclined planes. An essential preliminary to widespread adoption of locomotives was, as Stephenson well realized, improvements to the track. Although edge rails were stronger than plate rails, particularly when they were ‘fish-bellied’, cast-iron rails could be no more than about a metre long, and track laid with them was a continuous succession of joints. Rails rolled from malleable iron provided the answer, for not only could they be made as much as 3m (15ft) long, but they were not brittle. In 1821 an Act of Parliament was obtained for the Stockton & Darlington Railway: Stephenson persuaded the promoters to use both malleable iron rails and locomotives and became the railway’s engineer. To build locomotives, George Stephenson, his son Robert and other partners set up Robert Stephenson & Co. in 1823. In 1825, George Stephenson surveyed a railway between Liverpool and Manchester, but a Bill for this line was rejected by Parliament. Later the same year, however, the Stockton & Darlington Railway was triumphantly opened, Stephenson’s latest locomotive Locomotion hauling a train made up of the company’s sole passenger coach and 21 wagons fitted with seats. In service, the S & DR used not only locomotives but also horse haulage, gravity operation and powered and self-acting inclined planes. The locomotives, RAIL 561 indeed, proved in the early years unreliable, for they did not steam well enough for a continuous journey as long as 30km (20 miles). Liverpool & Manchester In these circumstances the directors of the 50km (31 mile) Liverpool & Manchester Railway were uncertain what form of motive power to use. They had successfully obtained an Act of Parliament in 1826 for a route surveyed by Charles Vignoles, and two years later construction, under George Stephenson, was well advanced. An independent report recommended cable haulage. The L & M directors then decided to hold a prize competition to find a locomotive which would be ‘a decided improvement on any hitherto constructed’. This competition, the Rainhill Trials, was held in October 1829 on a completed section of the railway. Of the four steam locomotives which came to Rainhill, only one, the Rocket, proved able to do all that the organizers of the trials stipulated, and indeed far more (see Figure 7, p. 36). Rocket was built by Robert Stephenson & Co., and entered by a partnership of George and Robert Stephenson and Henry Booth. Robert at this date was developing locomotive design fairly rapidly, but it was Booth who suggested that the boiler of their trials locomotive should have not a single large-diameter fire tube (as was then usual) but a multiplicity of small- diameter copper tubes through which hot gases from the fire would pass. In this way the heating surface would be much increased, and so would production of steam. This multi-tubular boiler proved highly successful—Rocket achieved 48kph (30mph) against the stipulated 16kph (10mph) of the trials— and became the conventional form of locomotive boiler. A water-jacketed firebox, which in Rocket’s case had been added at the rear of the barrel, was soon incorporated into the structure of the boiler proper, and a smokebox, with chimney mounted upon it, added at the front. To the English, Booth and the Stephensons are the originators of the multitubular firetube boiler: the French credit Marc Seguin. Seguin had obtained two locomotives in 1828 from Robert Stephenson & Co. for the Lyons & St Etienne Railway, then under construction. They proved even less reliable than the locomotives on the Stockton & Darlington, probably because curves on the St Etienne line were much more frequent and demands on the locomotives therefore greater. Seguin designed a boiler of return-tube type, in which the return part was multi-tubular. After experiments with a stationary boiler of this pattern, Seguin built a locomotive incorporating it in 1829, but whether this or Rocket was completed first is uncertain. Seguin and Booth were, however, ignorant of one another’s activities at this period. Seguin’s locomotive would not have steamed as well as Stephenson’s for, unlike Rocket, in which exhaust steam was turned up the chimney, it relied on fans to blow the fire. . means of the ‘head rope’, there was attached to the rear of the train the ‘tail rope’ from the previous engine, running off an out -of- gear winding drum. When the wagons arrived at the engine, the. developed and information was gathered about the effects of depth and of compressed air and other factors on the divers themselves. Following the First World War, gold was recovered from both the Laurentic. by the Lancaster Canal Co. in 1803–4. The deep valley of the River Ribble separated two completed sections of the canal, and a tramroad was built to link them which descended by inclined planes