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A galley is a warship propelled primarily by oars, but also having masts and sails. Galleys fought in the wars of ancient Persia, Greece, Carthage and Rome until the 4th century. They were revived by the medieval Mediterranean states from the 14th century until they were rendered obsolete by the ocean-going man of war. The Battle of Lepanto (1571) was the last great naval battle in which the galley played the principal part.
Galleys travelled the Mediterranean from perhaps 3000 BC. The first ships to navigate the Mediterranean were merchant ships with square-rigged sails built by the Greeks and Phoenicians. The first military vessels, described in Homer and represented in paintings, had a single row of oarsmen along each side in addition to the sail to provide speed and manoeuvrability.
These early sailors had very little in the way of navigational tools. CompassThis article is about the navigational tool. For other meanings, see Compass (disambiguation A compass (or mariner's compass is navigational instrument for finding directions. It consists of a magnetised pointer free to align itself accurately with Earth'es were not used for navigation until the 13th century12th century 13th century 14th century other centuries) As a means of recording the passage of time, the 13th century was that century which lasted from 1201 to 1300. Events Fourth through eighth crusades of western European kingdoms against Islam Fall of, and the development of sextantA sextant is a measuring instrument used to measure the angle of elevation of a celestial object, traditionally the Sun above the horizon. Knowing the angle and time of day, traditionally mid-day for the sun, one can calculate the degree of latitude.s, octants and accurate chronometerA chronometer is a clock designed to have sufficient long-term accuracy that it can be used as a portable time standard on a vehicle, usually in order to determine longitude by means of celestial navigation. Today only timepieces certified by the COSC mays together with the mathematics required to determine longitudeMap of Earth showing vertical lines of longitude Longitude sometimes denoted λ, describes the location of a place on Earth east or west of a north-south line called the Prime Meridian. Longitude is given as an angular measurement ranging from 0° at and latitudeLatitude denoted φ, gives the location of a place on Earth north or south of the Equator. Latitude is an angular measurement ranging from 0° at the Equator to 90° at the poles. Usually, the difference in latitude largely affects the climate and/or wea had to wait until considerably later. The ancient sailors navigated by means of the sun and the prevailing wind, and by the first millennium BC were using the stars to navigate at night, but if they were blown out of sight of land then they were lost.
The development of the ram in about 800 BC changed the nature of naval warfare, which had until that point been a matter of boarding and hand-to-hand fighting. Now the more manoeuverable ship could render the slower ship useless by staving in its sides. There is some doubt as to whether defeated galleys were usually sunk. The Greek word for "sunk" can also mean "waterlogged" and there are reports of victorious galleys towing the defeated ship away after the battle. The paucity of archaeological remains of sunken ships, in comparison with the abundance of galleys according to the writings of contemporaries, is further evidence that it was not common practice to sink the defeated ship.
Building an efficient galley was a difficult task. A ship travelling at high speed creates a bow wave and has to expend considerable energy climbing this wave instead of increasing its speed. The longer a ship is, the faster it can travel before being hampered by this effect, but long ships were difficult to construct with the available technology. Through a process of trial and error, the monoreme — a galley with one row of oars on each side — reached the peak of its development in the penteconter, about 38 m long, with 25 oarsmen on each side. It is believed that it that could reach speeds of about 9 knots (18 km/h), only a knot or so slower than modern rowed racing boats. The penteconter was large enough that cables stretched between the bow and stern were necessary to distribute the stress evenly.
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