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Ships and Shipbuilding, the types and construction of any large buoyant type vessel in which people travel or transport goods over the surface of the water. The term boat usually denotes smaller vessels, but no criterion of differentiation is generally accepted. The term shipbuilding is applied to the construction of large vessels. See also Boats and Boatbuilding.
At about the same time the Chinese developed one of the strongest and most
seaworthy vessels in existence: the junk, which is still used by the peoples of
Southeast Asia. Essentially a large, light flat-bottomed box, the junk lacks
three components elsewhere regarded as fundamental to ships: keel, and stem- and
sternposts (upright members at bow and stern). Its hull is partitioned off by
solid bulkheads running lengthwise and crosswise to divide it into watertight
compartments. Such bulkheads, which were not adopted by the West until the 19th
century, not only make the ship structurally rigid, but also protect it against
sinking. The lack of a keel is compensated for by a heavy steering oar or
rudder, mounted on the centerline through a watertight housing in the bottom.
The rudder can be raised or lowered. The sails are made up of narrow horizontal
linen or matting panels, each secured by its own line or sheet, so that each
sail can be quickly spread or closed.
By the 9th century AD, Chinese junks were carrying merchants
to Indonesia and India. In his Travels, written in 1298, the Italian traveler
Marco Polo praised the bulkhead system that kept the vessel from sinking "if she
springs a leak by running against a rock, or on being hit by a hungry whale." By
the 15th century junks were sailing to East Africa.
The ships of medieval Europe were, in
general, developments of the Roman galleys, but they used much longer oars, or
sweeps. These oars frequently were as long as 15 m (50 ft) and were powered by
as many as seven rowers at each oar. The inboard portions of the oars were
counterbalanced and equipped with handles; the rowers were arranged in tiers on
ramps. To provide greater leverage for the long oars, the tholes, or pins,
against which the oars were pulled, were mounted outside the hull of the ship on
a wooden framework, called an apostis, running parallel to the centerline of the
ship. First used on ancient galleys and reintroduced on medieval ships, the
apostis had the same purpose as the outriggers used on modern racing shells. Use
of the apostis also facilitated the arranging of the oars in two or more banks
on each side of the vessel.
Other improvements introduced in the Middle Ages included the
use of a permanent rudder hung from the sternpost of the ship in place of the
steering oars used by the Romans. In addition, the ships of later medieval times
were made with a greater freeboard (higher sides above the waterline) to make
them more suitable for use in rough or stormy seas.
The typical warship of the Middle Ages was the medieval
galley, which was brought to perfection by shipbuilders of the Mediterranean
area, particularly by the builders of Genoa and Venice. Galleys varied in length
from 30 to 60 m (100 to 200 ft) and were commonly propelled by 20 oars on each
side together with sails rigged on two or three masts. Beginning with the 15th
century, galleys were armed with cannon on the forecastle deck and on the high
poop deck at the stern. In later models of the galleys, guns were also mounted
to fire broadside over the bulwarks of the ship and, still later, to fire
through openings or ports in the bulwarks. The larger galleys carried as many as
1200 men.
Until the end of the Middle Ages no clear distinction was
made between naval and merchant sailing ships; vessels with sails were used both
as warships and as merchant ships, although oared ships were restricted largely
to military purposes. At about the beginning of the 15th century, however,
various nations began to develop distinctive types of vessels for fighting and
trade. A typical merchant ship of the late Middle Ages was the carrack, a
strongly built, three-masted vessel, carrying two courses of square sails on the
foremast and mainmast and a lateen sail (a triangular sail attached to both a
mast and a yard) on the short mizzenmast. Such ships were equipped with only a
limited amount of armament and were designed primarily for carrying cargo.
Near the end of the Middle Ages the use of oars for propulsion began to give way
to the exclusive employment of sails, particularly in vessels built in northern
Europe for use in the Atlantic Ocean. The Mediterranean nations, particularly
Italy, continued to build galleys, and as late as 1571 the Christian fleet that
fought the Turks at the Battle of Lepanto was composed almost exclusively of
galleys. Subsequently, various classes of rowing-and-sailing warships, such as
the galleon, were developed by the Mediterranean nations; these types replaced
the galley ships by the late 1700s.
European nations developed many types of sailing ships. The caravel, typical of
Portugal and Spain, was a comparatively small vessel, usually of about 113
metric tons burden (cargo capacity), but sometimes larger or smaller. The
caravel had a broad bow and a high, narrow poop deck. It was rigged with three
or four masts, of which only the foremast carried a square sail, while the
others carried lateen sails. The ships in which Christopher Columbus sailed on
his voyages of discovery were caravels.
The typical European warship of the 16th and 17th centuries
was the so-called great ship, with four or five masts, high forecastle and poop
decks, and two or more tiers of guns. These ships reached displacements of 900
metric tons or more and carried at least 60 guns. Later, armaments were
increased, particularly in the British navy, so that ships of 100 guns were not
uncommon. The flagship of the British admiral Horatio Nelson, the HMS Victory,
built in the middle of the 18th century, typified the large man-of-war style of
the period. The Victory was 56.7 m (186 ft) in length, 15.9 m (52 ft) in beam or
width, and had a displacement of 2197 metric tons. Lighter types of warship were
the frigate and sloop, or corvette, full-rigged ships, carrying 36 or fewer
guns, usually all mounted on deck rather than below decks as in the great ships.
Other small naval vessels of the 18th and 19th centuries included brigs,
brigantines, schooners, cutters, and luggers. For present-day naval ships, see
Naval Vessels.
Though gradually increasing in size and with minor improvements in detail,
sailing ships remained unchanged in their essentials for the three centuries
following Columbus's voyages. The renowned clipper ship, which brought a
remarkable advance in speed, was introduced only near the end of the
sailing-ship era in the mid-19th century. Its predecessor, the Baltimore
clipper, which was developed around the time of the American Revolution,
established an international reputation for swiftness and was particularly
successful in blockade running and privateering during the War of 1812. Slightly
modified and enlarged to accommodate up to approximately 450 metric tons burden,
Baltimore clippers were used as fast mail and passenger packet ships in the
transatlantic trade after the war.
The true clipper ships, which replaced the Baltimore
clippers, were the highest development of the commercial sailing ship, combining
speed and seaworthiness. Long, slender, and sharp-bowed, clippers excelled in
long-distance commerce, such as the U.S.-China trade and the Britain-India
trade. The trade between the west and east coasts, brought on by the California
gold rush of 1849, accelerated the need for fast-moving ships. As a result,
during this time numerous speed records were set.
The largest clipper ever built was the Great Republic, built in 1853 by Boston
naval architect Donald McKay, whose clippers set many of the records for
transatlantic, New York-to-San Francisco, and around-the-world voyages.
American wooden ships, particularly the clippers, dominated all ocean trade until the depression of 1857, when the British took the lead in the construction of so-called composite ships, which were planked with wood over iron frames, and in the construction of iron ships. Ships of the composite type, such as the British Cutty Sark, carried a major portion of the ocean freight of the world until approximately 1900, but they were unable to compete with steamships for the premium rates offered for fast freight service. In the Australian grain trade with Great Britain, sailing ships were used as late as the 1920s. These sailing ships were often made of steel and were usually rigged as barques, because this rig could be sailed with a smaller crew than the ship-rigged vessels. For the American coastal trade, many large schooners were constructed and were used until shortly after World War I. These schooners had four or more masts, could carry large quantities of cargo because of their fore-and-aft rigs, and could be handled by a comparatively small crew. The largest of these schooners was the seven-masted Thomas W. Lawson, built in 1902, which was a steel vessel with a tonnage of well over 5000. See Sail; Sailing.
Contributed by: Howard I. Chapelle
"Ships and Shipbuilding," Microsoftฎ Encartaฎ 97 Encyclopedia.
ฉ 1993-1996 Microsoft Corporation. All rights reserved.
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Last Revised: July 19, 2006 07:31 PM.
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