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PART THREE: TRANSPORT 522 later, similar sails were set between the masts. Other improvements came with the increasing size of ships, and with the need to carry more sails for greater speed; individual sails became larger and increased from one or two to three or four on each mast by 1800. The masts themselves, becoming loftier and more square in proportion, soon outran the average tree and had to be assembled from two or three sections, one above the other; often, too, the largest sections had to be ‘made’ from smaller timbers. Sails were cut better and set more tautly to obtain the best from the wind: blocks, containing pulleys to increase manual capacity when hauling on ropes, appeared at an early stage, and multiple blocks with metal sheaves and bearing made running rigging easier to work. Changes in hull design also improved the qualities of ships. The basic layout, with a deep waist between high castles, remained, but the forecastle was soon much reduced in height. The aftercastle, later known as the poop or quarter- deck, remained somewhat more pronounced and provided accommodation for officers and passengers, if any. The sheer, or fore-and-aft curve of the deck, was also gradually reduced, which greatly reduced the wind resistance of these ships and made them more weatherly. To accommodate the mizen mast, tiller steering had given way in the fifteenth century to the whipstaff, a vertical lever which operated a yoke attached to the rudder; this in turn was succeeded in about 1710 Figure 10.2: A Flemish ship of c. 1560. PORTS AND SHIPPING 523 by the wheel and tackles, making ships much more manageable. For example, in 1700 flag officers of the British navy were still making sure that the ‘great ships’ were safely in harbour by the end of September; but in 1759, Admiral Hawke was able to maintain the blockade of Brest far into November and then fight a decisive battle close inshore in Quiberon Bay in a rising gale. During the period from 1500 to about 1850 the average merchantman was designed along similar lines to the contemporary warship, although at 100–200 tonnes it would have been much smaller. However, much uncertainty still exists about the detailed layout of early merchant vessels, at least until the emergence of the Dutch fluyt at the end of the sixteenth century (Figure 10.3). This was a capacious three-masted vessel, rounded at the stern, cheap to build and run, without armament and so needing only a small crew. A sound bulk carrier, it was the basis of Dutch commercial supremacy and was copied by other seafaring nations. The largest merchant ships were the East Indiamen (Figure 10.4), of all nations, usually 500–600 tonnes in the seventeenth and eighteenth centuries, but rising to 1200 tonnes in the 1790s. These tonnages compare with the 500 and upwards of a small naval frigate, rising to more than 2000 for a first rate ship of the line. Such big ships were approaching the limits for wooden construction, and schemes were being evolved for strengthening them. Gabriel Snodgrass introduced a straighter side to the hull and a flat upper deck, much improving the strength of the whole, and Sir Robert Seppings, master shipwright at the Figure 10.3: A Dutch ‘fluyt’ of the early seventeenth century. PART THREE: TRANSPORT 524 Chatham naval dockyard, developed a system of diagonal bracing to increase the strength of wooden hulls. In actual hull form there were few developments, although Sir Anthony Deane in England, Frederick af Chapman in Sweden and various French naval architects made advances in the theoretical principles of sailing performance. (French ships had a good reputation for speed, but were often found to be weak in construction.) The Baltimore clipper (in fact a schooner), which emerged in the early nineteenth century, represented the most important development to date in hull form: its long, low profile, with sharply raked stem and overhanging stern counter, resulting in the minimum area possible in contact with the water, made these revolutionary vessels the fastest then afloat. Another important innovation of the eighteenth century was coppering, or sheathing ships’ bottoms with copper plates (earlier experiments with lead having proved unsatisfactory) to protect them from boring by shipworms and fouling by barnacles and weed. Once it was recognized that copper nails must be used, to avoid the galvanic reaction that occurred between the copper plating and the iron bolts at first used to attach it, coppering much improved ships’ speed, as well as reducing the need for maintenance, and it was widely adopted after 1780. Figure 10.4: A merchant ship of the late eighteenth century. PORTS AND SHIPPING 525 The nineteenth century From the early 1800s the very considerable increase in the volume and extent of trade, especially to more distant parts of the world, created economic conditions that encouraged both more and still larger ships and new commercial methods. By 1815, although the majority of merchant ships continued to be built along conventional lines, some significant changes began. Several trades demanded greater speed, sometimes, as in the tea trade, to reach markets quickly, in other less reputable activities, such as the slave trade, to elude pursuers. Many more passengers were seeking conveyance, and regularity of performance began to be important. Although steam would not become a serious competitor on most ocean voyages until around 1850, economical working became more necessary as the expanding markets stimulated increased competition alongside their many opportunities. The square-rigged three-master was initially supplanted for coastal trading, by the brig, similarly rigged but with only two masts, but the sharp and fine Baltimore hull form, schooner rigged (fore-and-aft sails on two or more masts, with square topsails on the foremast), steadily replaced both ship and brig. For longer voyages the same fast and economical hull was applied to larger and larger square-rigged vessels, for their size slowly but steadily increased. These fast square-riggers were the true clippers, famous in the China tea trade from the 1840s. They were also run by some of the Atlantic packet lines, which carried mail under government contract and therefore needed to offer speedy, reliable and regular service; here, too, the threat posed by steam made speed crucial. The discovery of gold in California in 1848, and in Australia in 1852, created a demand for passages at any price and, as steamships could not yet undertake such long voyages, the clippers, mostly built in the USA of softwood, prospered. Even after the boom years clippers, now mostly British built, continued until about 1870 in the China trade and 1890 in the passenger and wool trades to Australasia, and their example encouraged smarter sailing in general. After 1860 iron rapidly replaced wooden construction for deep-sea vessels. The larger sizes already in existence were too much for wood—the American clippers quickly wore out—and by the early 1870s ships of over loom long were being built. Concomitant improvements in rigging were needed: sails had reached their maximum practicable size and were subdivided, and were fitted with patent reefing systems such as Cunningham’s, which enabled the area of sail to be reduced without sending so many men aloft. Iron or steel masts and yards, and wire rigging, replaced wood and hemp, and sometimes sailing ships had steam-powered donkey engines to drive their winches, all of which allowed crews to be reduced. These improvements helped sail to remain competitive, even after the opening of the Suez Canal in 1869 (see p. 505) enabled steamships to take over PART THREE: TRANSPORT 526 more and more of the main trades between the Orient and Europe. In the 1870s four-masted ships and barques (three-masters, square-rigged on fore-and mainmast, fore-and-aft rigged on mizen, see Figure 10.4) were extensively built, largely for bulk cargoes such as grain and nitrates. Later a few five-masters were built. Big sailing ships of 1500 to over 3000 tonnes remained profitable for bulk trades and were built up to the 1890s, a few even up to 1905, but after that date their decline was rapid. A few survived in the Australian grain trade and the Baltic timber trade between the wars. The other characteristic type of the last days of commercial sail was the schooner (see p. 524), still commonly built of wood until 1900. Small coastal schooners remained very active until 1914, while in North America some very large craft of this rig were built for coal and timber carrying, many with four or more masts, one with seven. Since the 1970s evidence of an increasing energy crisis has directed attention once more to the use of wind power for shipping. Taking advantage of aeronautical discoveries, controllable sails of aerofoil type have been fitted to several otherwise conventional cargo vessels, but the economic benefits have yet to be measured. Figure 10.5: An iron clipper of the 1870s—the Piako. PORTS AND SHIPPING 527 STEAMSHIPS Paddle steamers Paddle-wheels, operated by men or animals, are said to have been used by the Chinese to power small craft at an early date, and there were vessels driven by treadmill in European waters during the seventeenth century. Early attempts to propel boats by means of steam-driven paddle-wheels were those of Denis Papin (1707); the Marquis de Joffroy d’Abbans (1776), who in 1783 used a horizontal double-acting steam engine developed independently of Boulton and Watt; and the American John Fitch (from 1786), whose experiments included the use of steam-driven oars. Financial backing, however, was not forthcoming until William Symington’s Charlotte Dundas, driven by a stern paddle-wheel between two hulls, became the first commercial steamship, operating on the Forth and Clyde Canal from 1802. Other pioneers included Robert Fulton, whose Clermont, with a pair of side paddle-wheels, ran commercially on New York’s rivers from 1807, and Henry Bell, with the first coastal steamer, the Comet of 1812, which ran off the west coast of Scotland. By about 1825 there was an extensive system of steamship services around the British Isles and to Europe, as well as on American rivers. The majority of these vessels were side-wheel paddle steamers with low-pressure non- condensing engines, conforming (with suitable strengthening for engines and boilers) to normal wooden ship layout. The first transatlantic steamship crossing has been claimed for the American Savannah as early as 1819, but she was a hybrid vessel and completed most of the voyage under sail. Among early eastward crossings under steam, the twenty-five-day voyage of the Royal William in 1833 is notable. However, transatlantic steam navigation as a commercial reality dates from 1837, with both the Sirius and Isambard Kingdom Brunel’s first marine essay, the Great Western, designed to extend the Great Western Railway from Bristol to New York. The British government, recognizing the political and commercial value of fast, regular communication with distant regions, was quick to support the establishment of four subsequently famous shipping companies: the Royal Mail Steam Packet Co (1839) to the West Indies and South America; the Peninsular Steam Navigation Co. (1840, later the Peninsular and Oriental) to India and later Australia and the Far East; the Cunard company (1840) to North America; and the Pacific Steam Navigation Co. (1839) for service along the west coast of South America. These routes usually employed ships of 1500–2000 tonnes with large engines, usually of side-lever type, by now fitted with jet or surface condensers which conserved fresh water. PART THREE: TRANSPORT 528 Iron ships and screw propulsion The Staffordshire ironmaster John Wilkinson and others had experimented with iron hulls before the end of the eighteenth century, using the methods of wooden ship construction, but the idea was long regarded with scepticism. By the 1840s, however, even sailing ships were beginning to outgrow the capabilities of wood; it was becoming evident, too, that the strength of iron would allow the building of hulls that were not only larger but which could be clear of structural members, improving cargo capacity and handling as well as the flexibility of ship layout. The screw propeller seems to have been invented almost simultaneously in 1836, by Francis Pettit Smith in England and John Ericsson in Sweden; in 1845 the British Admiralty conducted trials between two identical frigates, the Alecto, with a pair of paddle-wheels, and the screw- driven Rattler, in which the latter was clearly superior. Brunel’s second ship, the Great Britain of 1845, was a very large (over 3000 tonnes) iron screw ship of advanced design, with the first watertight bulkheads. The minor damage she incurred on running aground in Dundrum Bay, Ireland, in 1847 demonstrated the strength of her hull construction. His Great Eastern of 1858, designed to run to the Far East, was even more far-sighted, a vast ship of nearly 19,000 tonnes and more than 200m long, with both a screw and a pair of paddle-wheels to provide sufficient power. Although both ships were technically successful, they were too large for the commercial needs of their time and were not emulated. Figure 10.6: An early paddle steamer—the Clarence. PORTS AND SHIPPING 529 From about 1860 to the present day, merchant ships and warships followed different lines of development and must be considered separately. MERCHANT SHIPPING Apart from a short period when composite construction (iron frame with wooden planking) was popular, after 1860 only iron ships were built for ocean work, to be replaced from 1880 by the steel made widely available by the Siemens-Martin process (see p. 171). While hull structure followed in essentials that of wooden ships, with keel and ribs to which the plates were bolted, later riveted, iron and steel sections were far less bulky than wood. It was also now possible to install watertight bulkheads and double bottoms (both pioneered by Brunel) and to adapt the hull for a variety of specialized requirements, whether for cargo, for a particular route or, as became increasingly the case, to minimize harbour and other dues calculated on tonnage. In the bigger ships made feasible by iron, multiple decks could be provided for more and better passenger accommodation (a trend that had begun with the largest wooden Atlantic packets), and steamers with three, four and eventually more decks were built. With cargo vessels the introduction of the screw propeller rapidly brought steam to the forefront. The original bulk carrier steamships, built by Charles Mark Palmer and others for the coal trade between the north-east of England and London, were one-deck ships and the first to use water ballast tanks to reduce turnaround time in port, an invention attributed to John McIntyre. Very quickly these ships extended their activities further afield, becoming the predecessors of the tramp steamers. For regular trades more complex ships appeared with several separate holds and one or two lower decks, allowing cargo to be stowed according to its type or destination. The vast majority of these steamships were driven by screw engines. Paddle steamers were retained until the early 1860s by the ocean contract packets, and until well into the twentieth century by river, coastal and cross-channel passenger steamers, especially where high speed was required and where the diameter of a large single screw was too great for the available draught of water. On such routes, too, the availability of fuel was not a major consideration, but on longer voyages it virtually governed the extension of commercial steam navigation, other than the subsidized mail services. A world- wide network of coaling stations was established to replenish the bunkers of steamships on ocean voyages—the lack of possible sites for such facilities significantly delayed the introduction of steamship services to Australasia—and the supply of these ports provided in itself an extensive trade for the preferred Newcastle and South Wales coal as well as from other sources. The development of more economical engines and boilers progressed steadily to PART THREE: TRANSPORT 530 answer this problem. Attempts were made in the 1850s to use steam twice, but it was not until the mid-1860s that the famous Holt engine and other designs brought the compound engine into practical use combined with improved boiler construction to allow higher pressures. Holt’s Ocean Steamship Company’s service to China in 1866, combined with the opening of the Suez Canal in 1869, marked the death-knell of sail on the routes to India and the Far East in favour of compound steamships. From this period, too, the tramp steamer emerged, delivering and picking up freight in an ad hoc manner from port to port and making serious inroads into the bulk cargoes carried by large sailing ships. With the development of the triple expansion engine (see p. 286) about 1880, the last bastions of sailing ships as regular passenger and high quality cargo carriers were threatened—the routes to Australia and New Zealand. Both countries, as well as Argentina and the Mid-west of the United States, also provided more bulk cargoes for the tramp steamers, such as grain to feed the industrial populations of western Europe, and refrigeration developed to the point where large consignments of frozen meat in fast cargo ships became a prime business. In the same period, the 1880s, engines for fast ships were produced, running at higher revolutions and much more compact, and in the 1890s quadruple expansion engines came into use. Twin screws had been tried earlier, with limited success, but also in the 1890s they were widely adopted and, to provide increased power for larger and faster ships, triple and quadruple screws were introduced. The great expansion in trade, and in commercial methods, allowed larger cargoes to be readily handled and opened the way for the economic use of the much bigger ships already shown to be feasible by the Great Eastern. In the 1870s the long ship was pioneered by the Belfast shipbuilders Harland & Wolff, with a length: beam ratio of 9 or 10:1, and from the 75m (248ft) of the 1860s the length of the largest ships rose to more than 120m (394ft); an especially rapid enlargement during the 1890s brought lengths up to 200m (65 6ft) or more, with beam increasing rather more in proportion to around 7 or 8:1. By 1914 great liners of 240m (787ft) were in service. Until the 1890s virtually all the passenger accommodation was in the hull, but as facilities grew more and more luxurious it was sited on the hull in superstructure. As more power needed more boilers, the great ‘funnel race’ began, the number of funnels being regarded as an index of quality. Further important changes in the engine room accompanied these advances to produce the merchant ship as it was to remain until the 1970s. The water-tube boiler was developed in various forms and, after much trouble, eventually became a reliable steam producer, especially when combined with the Parsons steam turbine (see p. 290). The early turbines were directly coupled to the propeller, but by 1914 gears had been developed to a state where they could be inserted into the shaft to give slower and more PORTS AND SHIPPING 531 economical propeller speeds. In some ships low-pressure turbines were fitted together with reciprocating engines. From the 1880s, Russia used indigenous petroleum fuel for ships’ boilers, and by 1914 copious supplies of oil were being produced by the countries around the Persian Gulf. Its advantages as a fuel, and its ease of handling and cleanliness compared with coal, ensured its popularity; and after 1918, in more stringent economic conditions, the savings it offered, in time and in the need for numerous stokers, made oil the most used fuel for steamships. It was also the fuel of a new and serious competitor to steam—the internal combustion or diesel engine (see p. 303ff.), first used in Russian vessels around the Caspian Sea. Much development work by the Danish firm of Burmeister & Wain made it suitable for ocean-going vessels; the Selandia of 1912 was the first deep-sea ship fitted with diesel engines, which made rapid progress especially among Scandinavian owners, while its application to submarines was crucial. Electric power was also adopted for ships, but with less widespread success. Current was generated by either steam or diesel engines and fed to motors which were small enough to occupy otherwise little-used space aft. While the installations were technically successful, electric drive was found to be uneconomic except in specialized cases where exact control was important, such as ferries or cable ships. The coal-fired steam engine did not remain untouched in this period of diversity, for many improvements were made in both reciprocating and turbine types, such as the use of higher steam pressures, poppet valves and other refinements such as mechanical stokers with pulverized fuel. Types of ship did not, in general change greatly, although there were many modifications of detail. The main novelty was, of course, the appearance of the oil tanker in large numbers, the first having been built in 1886. From the earliest days these vessels had their engines aft, a feature which became increasingly common on small coastal steamers. For safety reasons tankers had to be closely subdivided into numerous compartments, and they were equipped with expansion tanks and pumping systems to handle the cargo. The new Isherwood longitudinal system of construction, in which much of the strength is in stringers running fore-and-aft as well as in the more usual frames, was found especially advantageous for tankers. The inter-war period also saw a considerable increase in the number of refrigerated ships, not only for meat and dairy products but also for fruit. Other new methods of building were introduced, many to be of great utility in the emergency building programmes of the Second World War, such as the American Liberty ships. These included welding, instead of the time-honoured riveting of plates and sections, and large-scale prefabrication in shops away from the slip. Another change was in the use of lighter-weight materials for superstructures. . boilers, the great ‘funnel race’ began, the number of funnels being regarded as an index of quality. Further important changes in the engine room accompanied these advances to produce the merchant. 1807, and Henry Bell, with the first coastal steamer, the Comet of 1812, which ran off the west coast of Scotland. By about 1825 there was an extensive system of steamship services around the British. pronounced and provided accommodation for officers and passengers, if any. The sheer, or fore-and-aft curve of the deck, was also gradually reduced, which greatly reduced the wind resistance of these

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