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Методические указания Специальность 190701: «Организация перевозок и управление на транспорте (водном)» Новосибирск 2009 (стр. 5 из 20)



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ЧАСТЬ 4. ТЕКСТЫ ДЛЯ ЧТЕНИЯ И ПЕРЕВОДА
_____________________ (ЗА ЗКУРС)_______________________

HISTORY OF TRANSPORTATION

Early rowed vessels

The earliest historical evidence of boats is found in Egypt during the 4th millennium ВС. A culture nearly completely riparian, Egypt was narrowly aligned along the Nile, totally supported by it, and served by transport on its uninterruptedly navigable surface below the First Cataract (at modern-day Aswan). There are representations of Egyptian boats used to carry obelisks on the Nile from Upper Egypt that were as long as 300 feet (100 metres), longer than any warship constructed in the era of wooden ships.

The Egyptian boats commonly featured sails as well as oars. Because they were confined to the Nile and depended on winds in a narrow channel, recourse to rowing was essential. This became true of most navigation when the Egyptians began to venture out onto the shallow waters of the Mediterranean and Red seas. Most early Nile boats had a single square sail as well as one level, or row, of oarsmen. Quickly, several levels came into use, as it was difficult to maneuver very elongated boats in the open sea. The later Roman two-level bireme and three-level trireme were most common, but sometimes more than a dozen banks of oars were used to propel the largest boats.

Navigation on the sea began among Egyptians as early as the 3rd millennium ВС. Voyages to Crete were among the earliest, followed by voyages guided by landmark navigation to Phoenicia and, later, using the early canal that tied the Nile to the Red Sea, by trading journeys sailing down the eastern coast of Africa. According to the 5th-century-BC Greek historian Herodotus, the king of Egypt about 600 ВС dispatched a fleet from a Red Sea port that returned to Egypt via the Mediterranean after a journey of more than two years. Cretan and Phoenician voyagers gave greater attention to the specialization of ships for trade.

Model of a Phoenician ship, 13th century ВС. In the Museum of The Philadelphia Civic Center. The basic functions of the warship and cargo ship determined their design. Because fighting ships required speed, adequate space for substantial numbers of fighting men, and the ability to maneuver at any time in any direction, long, narrow rowed ships became the standard for naval warfare. In contrast, because trading ships sought to carry as much tonnage of goods as possible with as small a crew as practicable, the trading vessel became as round a ship as might navigate with facility


(see photograph). The trading vessel required increased freeboard (height between the waterline and upper deck level), as the swell in the larger seas could fairly easily swamp the low-sided galleys propelled by oarsmen. As rowed galleys became higher-sided and featured additional banks of oarsmen, it was discovered that the height of ships caused new problems. Long oars were awkward and quickly lost the force of their sweep. Thus, once kings and traders began to perceive the need for specialized ships, ship design became an important undertaking.

As was true of early wheeled vehicles, ship design also showed strong geographic orientation. Julius Caesar, for one, quickly perceived the distinctive, and in some ways superior, qualities of the ships of northern Europe. In the conquest of Britain and in their encounter with the Batavian area in Holland, Romans became aware of the northern European boat. It was generally of clinker construction (that is, with a hull built of overlapping timbers) and identical at either end. In the Mediterranean, ship design favoured carvel-built (that is, built of planks joined along their lengths to form a smooth surface) vessels that differed at the bow and stern (the forward and rear ends, respectively). In the early centuries, both Mediterranean and northern boats were commonly rowed, but the cyclonic storms found year-round in the Baltic and North Sea latitudes encouraged the use of sails. Because the sailing techniques of these early centuries depended heavily on sailing with a following wind (i.e., from behind), the frequent shifts in wind direction in the north permitted, after only relatively short waits, navigation in most compass directions. In the persistent summer high-pressure systems of the Mediterranean the long waits for a change of wind direction discouraged sailing. It was also more economical to carry goods by ship in the north. With a less absolute dependence on rowing, the double-ended clinker boat could be built with a greater freeboard than was possible in the rowed galleys of the Mediterranean. When European sailors began to look with increasing curiosity at the seemingly boundless Atlantic Ocean, greater freeboard made oceanic navigation more practicable.

Sailing ships

The move to the pure sailing ship came with small but steadily increasing technical innovations that more often allowed ships to sail with the wind behind them. Sails changed from a large square canvas suspended from a single yard (top spar), to complex arrangements intended to pivot on the mast depending on the direction and force of the wind. Instead of being driven solely by the wind direction, ships could "sail into the wind" to the extent that the course taken by a ship became the product of a resolution of forces (the actual wind direction and the objective course of the particular



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ship). Sails were devised to handle gentle breezes and to gain some mileage from them as well as from strong winds and to maintain some choice as to course while under their influence.

Types of sails

While the speed of a rowed ship was mainly determined by the number of oarsmen in the crew, in sailing ships the total spread of canvas in the sails was the main determinant of speed. Because winds are not fixed either as to direction or as to force, gaining the maximum effective propulsion from them requires complexly variable sails. There was one constant that characterized navigation by sail throughout its history - to gain speed it was necessary to increase the number of masts on the ship. Ships in both the Mediterranean and the north were single-masted until about AD 1400 and likely as well to be rigged for one basic type of sail. With experience square sails replaced the simple lateen sails that were the mainstay during the Middle Ages, particularly in the Mediterranean.

In the earlier centuries of sailing ships the dominant rig was the square sail, which features a canvas suspended on a boom, held aloft by the mast, and hung across the longitudinal axis of the ship. To utilize the shifting relationship between the desired course of the ship and the present wind direction, the square sail must be twisted on the mast to present an edge to the wind. Among other things this meant that most ships had to have clear decks amidships to permit the shifting of the sail and its boom; most of the deck space was thus monopolized by a single swinging sail. Large sails also required a sizable gang of men to raise and lower the sail (and, when reef ports were introduced, to reef the sail, that is, to reduce its area by gathering up the sail at the reef points).By 1200 the standard sailing ship in the Mediterranean was two-masted, with the foremast larger and hung with a sail new to ordinary navigation at sea. This was the lateen sail, earlier known to the Egyptians and sailors of the eastern Mediterranean. The lateen sail is triangular in shape and is fixed to a long yard mounted at its middle to the top of the mast. The combination of sails tended to change over the years, though the second mast often carried a square sail

One broad classification of sails, which included the lateen, was termed "fore-and-aft" sails - that is, those capable of taking the wind on either their front or back surfaces. Such sails are hung along the longitudinal axis of the ship. By tacking to starboard (the right side) the ship would use the wind from one quarter. Tacking to port (the left side) would use a wind coming from the opposite quarter to attain the same objective.


Asian ships

During this same period China, with its vast land areas and poor road communications, was turning to water for transportation. Starting with a dugout canoe, the Chinese joined two canoes with planking, forming a square punt, or raft. Next, the side, the bow, and the stern were built up with planking to form a large, flat-bottomed wooden box. The bow was sharpened with a wedge-shaped addition below the water!ine. At the stern, instead of merely hanging a steering oar over one side as did the Western ships, Chinese shipbuilders contrived a watertight box, extending through the deck and bottom, that allowed the steering oar or rudder to be placed on the centreline, thus giving better control. The stern was built to a high, small platform at the stern deck, later called a castle in the West, so that, in a following sea, the ship would remain dry. Thus, in spite of what to Western eyes seemed an ungainly figure, the Chinese junk was an excellent hull for seaworthiness as well as for beaching in shoal (shallow) water. The principal advantage, however, not apparent from an external view, was great structural rigidity. In order to support the side and the bow planking, the Chinese used solid planked walls (bulkheads), running both longitudinally and transversely and dividing the ship into 12 or more compartments, producing not only strength but also protection against damage.

In rigging the Chinese junk was far ahead of Western ships, with sails made of narrow panels, each tied to a sheet (line) at each end so that the force of the wind could be taken in many lines rather than on the mast alone; also, the sail could be hauled about to permit the ship to sail somewhat into the wind. By the 15th century junks had developed into the largest, strongest, and most seaworthy ships in the world. Not until about the 19th century did Western ships catch up in performance.

Early oceanic navigation

The rise of oceanic navigation began when the basic Mediterranean trading vessel, the Venetian buss (a full-bodied, rounded two-masted ship), passed through the Strait of Gibraltar. At the time of Richard I of England (reigned 1189-99), whose familiarity with Mediterranean shipping stemmed from his participation in the Crusades, Mediterranean navigation had evolved in two directions: the galley had become a rowed fighting ship and the buss a sail-propelled trader's vessel. From Richard's crusading

expeditions the value of the forecastle and after castle - giving enclosed deck houses and a bulging bow of great capacity - was learned, and this

style became the basis of the English oceangoing trader. These crusading



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voyages also introduced the English to journeys longer than the coasting and North Sea navigation they had previously undertaken.

The story of European navigation and shipbuilding is in large part one of interaction between technical developments in the two narrow boundary seas. It is thought that sailors from Bayonne in southwestern France introduced the Mediterranean carrack (a large three-masted, carvel-build ship using both square and lateen sails) to northern Europe and in turn introduced the double-ended clinker ship of the north to the Mediterranean. This crossfertilization took place in the 14th century, a time of considerable change in navigation in the Atlantic-facing regions of France, Spain, and Portugal.

Changes in shipbuilding during the Middle Ages were gradual. Among northern ships the double-ended structure began to disappear when sailing gained dominance over rowing. To make best use of sails meant moving away from steering oars to a rudder, first attached to the side of the boat and then, after a straight stern post was adopted, firmly attached to that stern. By 1252 the Port Books of Damme in Flanders distinguished ships with rudders on the side from those with stern rudders

The arts of navigation were improving at the same time. The compass was devised at the beginning of the 14th century, but it took time to understand how to use it effectively in a world with variable magnetic declinations. It was only about the year 1400 that the lodestone began to be used in navigation in any consistent manner.

15-ccntury ships and shipping

The early 15th century saw the rise of the full-rigged ship, which had three masts and five or six sails. At the beginning of that century Europe and Asia were connected by caravan routes over land. The galleys or trade ships were long, low-sided, commonly rowed for much of their voyage, and guided by successive landfalls with little need for the compass and mathematical navigation. By the end of the century Da Gama, Columbus, and Cabot had made their revolutionary journeys, the Portuguese had organized the first school of oceanic navigation, and trade had begun to be global.

"Full-rigged" ships were introduced because trade was becoming larger in scale, more frequent in occurrence, and more distant in destination. There was no way to enlarge the propulsive force of ships save by increasing the area of sail. To pack more square yards of canvas on a hull required multiple masts and lofting more and larger sails on each mast. As multiple masts were added, the hull was elongated; keels were often two


and a half times as long as the ship's beam (width). At the beginning of the 15th century large ships were of about 300 tons; by 1425 they were approximately 720 tons.

In the 16th century the full-rigged ship was initially a carrack, a Mediterranean three-master perhaps introduced from Genoa to England. The trade between the Mediterranean and England was carried on at Southampton largely by these carracks. As the years passed the galleon became the most distinctive vessel. This was most commonly a Spanish ship riding high out of the water. Although the name suggested a large galley, galleons probably never carried oars and were likely to be four-masted.

In earlier centuries ships were often merchantmen sufficiently armed to defend themselves against pirates, privateersmen. and the depredations of an active enemy. In peacetime a ship would go about its business as a nation's trader, but it was able to become a fighting vessel if necessary. When the size of guns and the numbers involved grew to create an offensive capability, there remained little space to carry the volume of goods required by a trader. What resulted was the convoy, under which merchantmen would be protected by specialized naval ships. The distinction between warship and trading ship might have remained quite abstract had not the theory and tactics of warfare changed. Most medieval wars were either dynastic or religious, and armies and navies were small by modern standards. But beginning with the warfare between the Dutch and the English in the 17th century, conflict was the result of competition in trade rather than in sovereignty and faith. Thus, the major trading nations came to dominate ship design and construction.

17th-century developments

With the emergence of the eastern trade about 1600 the merchant ship had grown impressively. The Venetian buss was rapidly supplanted by another Venetian ship, the cog. A buss of 240 tons with lateen sails was required by maritime statutes of Venice to be manned by a crew of 50 sailors. The crew of a square-sailed cog of the same size was only 20 sailors. Thus began an effort that has characterized merchant shipping for centuries to reduce crews to the minimum. This was particularly true of oceanic navigation, because larger crews were expensive to pay and to provision - and the large amounts of provisions necessary were sometimes critical on long voyages.

In the north, vessels were commonly three-masted by the 16th century. These were the ships that Cabot used to reach Newfoundland and



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Drake, Frobisher, and Raleigh sailed over the world's oceans. Raleigh wrote that the Dutch ships of the period were so easy to sail that a crew one-third the size used in English craft could operate them. Efforts were made to accomplish technical improvements on English copies of Venetian and Genoese traders. These ultimately resulted in the East Indiaman of the 17th century. This large and costly ship was intended to be England's entry in a fierce competition with the Dutch for the trade of India and the Spice Islands.

When Europeans began to undertake trading voyages to the East, they encountered an ancient and economically well-developed world. In establishing a sea link with the East, European merchants could hope to get under way quickly using the producers already resident there and the goods in established production. What resulted were European "factories," settlements for trade established on coasts at places such as Bombay, Madras, and Calcutta. Some European merchants settled there, but there was no large-scale migration; production of the goods followed established procedures and remained in Asian hands. In contrast, in the New World of America and Australia there was so little existing production of trading goods that the establishment of ties required not only the pioneering of the trading route but also the founding of a colony to create new production. Shipping was critical in each of these relationships but became larger and more continuous in the case of the colonies.

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