Galley (Fr. galere), a long, low, narrow vessel of war, propelled by oars and sails. The derivation of the word is uncertain, but it is generally supposed to be from galea, a helmet, either because it was used sometimes as a figurehead, or because the basket-like construction at the head of the mast, for the use of archers and slingers, was shaped like a helmet. The name was first applied under the Byzantine empire to this class of vessels, which the ancients designated, according to the number of banks of oars in each, biremes, triremes, quadriremes, etc. The first galleys were merely open boats, with a single rank of rowers on each side, and sometimes with a single mast and a square sail. The rowers were placed amidship and the fighting men in.the bow and stern. Platforms for combatants were soon built on the forecastle and stern, and bulwarks were raised for the protection of oarsmen; but it was not until the 3d or 4th century 13. 0. that the two platforms were connected so as to make a complete deck. The Egyptian war galleys of the 15th century B. C. differed very little in general construction from the Mediterranean galleys of the 17th century A. D. They were from 116 to 120 ft. long by 16 ft. wide, were propelled by both sails and oars, and were armed with a beak.

They are represented sometimes with 22 oars on a side, always ar-ranged in a single bank. According to Pliny, the Erythrseans were the inventors of the bireme, or galley with two banks of oars; Thucydides ascribes the trireme, with three banks, to the Corinthians; the quadrireme, with four banks, is said by Pliny and Diodorus to have been built first by the Carthaginians; and Mnesigiton ascribes the quinquereme, with five banks, to the Salaminians. In the times of Alexander the Great and the Ptolemies, galleys of 12, 15, 20, and even 40 banks of oars were built, according to ancient writers. A vast deal of learning has been expended in attempts to explain the method of arrangement of these oar banks, but it is still an unsolved problem. Some scholars maintain that the several banks were actually placed one above the other, and others that the benches were in rising grades, like stairs; but those familiar with naval construction reject these theories. A more plausible one is that of L'Escalier, who supposes that the three banks of the trireme were arranged, not one above the other, but all in a line, one amidship, one abaft the mainmast, and one forward of the foremast; and that in the quinquereme two banks, one above the other, were put amidship, two aft, and one forward.

The possibility of two superimposed banks is generally admitted, and some writers believe in three. On the column of Trajan is represented a trireme with three banks of oars one above another, but beyond this number we have no example. The Athenians used nothing but triremes for a long time, but in the 4th century B. C. quadriremes and quinqueremes were introduced. In the most flourishing state of their navy they seldom carried more than 10 fighting men in each galley, depending on superior seamanship and sinking an enemy by piercing him with the spur, rather than on overcoming him by a hand-to-hand conflict. The Romans adopted a different system when they built their first navy in the Punic wars. Of the 420 men in each quinquereme, 120 were combatants; and they fitted their galleys with a boarding bridge, by means of which an enemy's deck could be reached easily when the vessels were laid alongside of each other. Quinqueremes had usually two masts, each of which carried a square sail. These masts were lowered previous to going into action, and the galleys were manoeuvred by oars alone. In time experience proved the superiority of lighter vessels, and the trireme gradually supplanted other forms and came to be recognized as the best type of the war galley.

The Roman trireme was about 105 ft. long by 11 wide, and was manned by 170 rowers. After the time of Julius Cassar the trireme was 90 ft. by 10, differing from the Neapolitan and Maltese galleys, whose length seldom exceeded seven breadths. When propelled by both oars and sails their speed was very great, almost equalling at times that of the modern steamboat. In the ancient galleys each oar was pulled by a single man. The rowers were guided by the word of command or by the sound of a trumpet, and appropriate cries were adapted to each manoeuvre. The Greeks sometimes had musicians who regulated the movements by singing or by playing the flute or harp. In place of a rudder, galleys were furnished with a large broad oar on each side of the stern, and sometimes with two on each side. The galleys which under the eastern empire took the place of the trireme were of similar construction, but a little lower. They had two decks and two banks of 25 oars on each side, making 100 in all, were armed with a beak, and furnished with various engines for throwing darts and stones, or for dropping heavy weights on the deck of an enemy.

After the invention of Greek fire, tubes for spouting this liquid were fitted to the bow, and the bulwarks and deck were sometimes covered with raw hide to protect them from that thrown by an enemy. England under Alfred the Great excelled in her galleys, which carried from 40 to 60 rowers on each side. The forces of William the Conqueror were transported across the channel in galleys so small that they carried no more than 20 armed men besides the rowers. When Richard Coeur de Lion went to the Holy Land in 1190, he had, besides other ships, 38 war galleys; and the Saracens fought him with similar vessels. They differed very little from those of the early eastern empire. Geoffrey de Vinsauf describes them as long and graceful, not high out of water, with two decks and two banks of oars, and armed with a wooden spur shod with iron. A smaller and lighter vessel, with one bank of oars, used for despatch boats and for throwing Greek fire, was called a galleon. From this time onward galleys again played an important part in the Mediterranean. They were much used also in the northern seas. In 1295 Eric, king of Norway, furnished Philip the Fair 200 galleys for use in the war with Edward I. of England. In the 14th century and after galleys were divided generally into three classes.