| TERMS | MEANING: |
|---|---|
| OAR | A wooden instrument which, working as a lever, is used to pull a boat through the water. It has three parts: the blade, the part of the oar which enters the water; the shaft, the main body of the oar; and the loom, the inboard end on which the rower pulls. The point of leverage is the rowlock, crutch, or thole pin in the gunwale of the boat. It is so basic an adjunct of the sea that, according to legend, Ulysses/ Odysseus was told, on his retirement from a life at sea, that he should journey inland carrying an oar over his shoulder until he should find a people who asked him what it was he was carrying. There, after making a sacrifice to Neptune, he should build his house. |
| OCCULTING LIGHT | A navigational light displayed by a lighthouse or lightship in which the period of darkness is shorter than the period of light. |
| OCEAN | In its proper meaning, the whole body of water which encircles the globe with the exception of inland seas, lakes, and rivers. For more precise geographical purposes, the ocean is divided into five separate oceans—the Atlantic (North and South). Indian. Pacific. Arctic, and Antarctic. It has been calculated that the oceans cover 71 per cent of the whole area of the globe. |
| OCEAN RATING COUNCIL | An international body which supervises the rules under which racing yachts are rated. It is a complementary body to the International Yacht Racing Union. |
| OCEANIA | A term sometimes used to describe the South Seas but more accurately those south Pacific islands included in the area bounded by Hawaii in the north. Easter Island in the east. New Zealand in the south, and New Guinea in the west. This area is subdivided into Polynesia in the east, Micronesia in the north-west, and Melanesia in the south-west. |
| OCEANOGRAPHY | The science which deals with the phenomena common to the whole ocean. Attempts to particularize this science under the general name ‘thalassography’ have been resisted since it was first proposed by the Italian authorities at the end of the 19th century; similar attempts to align this science with the general title of hydrography have similarly failed to find favour, since oceanography is a wider study than pure hydrography. |
| OCTANT | A reflecting navigational instrument for measuring the altitude of heavenly bodies, having an arc of one-eighth of a circle, but because of its reflecting properties, capable of measuring altitudes of up to 90°. When John Hadley invented his reflecting quadrant in 1731, it was in fact an octant, but was still called a quadrant because that was the name by which all seamen called the existing common, or seaman’s, quadrant, even though Hadleys reflecting, or double image, sector doubled the degree of altitude which could be measured. Octants remained in use by navigators up to the 19th century, “sextants, which were introduced during the second half of the 1 8th century, being generally used for lunar observations in the calculation of longitude. When the introduction of chronometers made these involved lunar calculations no longer navigationally necessary, the sextant replaced the octant as the standard navigational instrument for the measurement of altitudes. |
| ODESSA | A principal seaport and naval base of southern Russia, in the north-west corner of the Black Sea. Originally it was a Greek settlement, but with the decay of Greek civilization in the 3rd and 4th centuries B.C., the settlements died away. The town was held by the Lithuanians from the 14th to 16th centuries when it was seized by the Tartars. The Turks occupied it during the early 18th century and in 1789 it was captured by Russian forces under French leadership, being finally ceded to Russia in 1791. It is from that date that development of Odessa as a major seaport and naval base was begun. During the Crimean War (1854-6) it was attacked unsuccessfully by an Anglo-French fleet: the Turks were equally unsuccessful during the Russo-Turkish War of 1876-7. |
| ODYSSEUS | According to Greek legend the son of Laertes and Anticleia and one of the most famous heroes of ancient Greece. After the capture of Troy, effected by his stratagem of the wooden horse, he set sail for Ithaca but unfavourable winds carried him along the coast of North Africa and across unknown seas to Italy, where he braved the dangers of Scylla and Charybdis. After many adventures he was, again according to legend, slain unknowingly in his old age by his son Telemachus. |
| OFF SOUNDINGS, or BEYOND SOUND INGS | A ship is off soundings when she is in waters which lie to seaward of the 100-fathom line. Before the days of sounding machines and echo-sounders, the deep sea lead line could measure depths up to about 100 fathoms, so that this was in those days the limit of soundings, all greater depths being off, or beyond, soundings. |
| OFF THE WIND | Said of a sailing ship when she is sailing with the sheets well eased off with the wind coming free or from broad on the bow. When a vessel sails as close to the wind as she can, she is on the wind. |
| OFFING | The distance that a ship at sea keeps away from the land because of navigational dangers, fog, or other hazards. The term is generally, though not necessarily, understood to mean that the ship remains in waters too deep for anchoring. To keep, or to make, a good offing, to lay a course which takes a ship well off the land and clear of all danger. |
| OLDSTER | In the old days of the British sailing navy a midshipman of more than four years’ seniority who, with the master’s mates, also known as oldsters, occupied the cockpit of the ship. Junior midshipmen of less than four years’ seniority were under the charge of the gunner in the gunroom. |
| OLERON, THE LAWS OF | A code of maritime law enacted by Eleanor of Aquitaine, who married Henry II of England in 1152, and attributed by her to the Island of Oleron, part of her duchy and renowned for the skill and courage of its seafaring population. It is possible that they were based on the older Rhodian Law of the Mediterranean. The laws dealt mainly with the rights and responsibilities of ships” captains in relation to discipline, mutiny, pay, cargoes, sickness on board, pilotage, and similar matters. The Laws of Oleron were introduced into England in about 1190 by Richard I. son of Henry and Eleanor of Aquitaine. And were codified in the Black Book of the Admiralty in 1336. |
| ON THE BEACH | Said of a seaman who has retired from sea service. |
| ON THE WIND | Said of a sailing vessel when she is sailing with her sheets hauled as far aft as possible, or as close to the wind as the ship will go. |
| OPEN HAWSE | The condition of a ship when she is lying to two anchors without the cables becoming crossed. It is the opposite of a foul hawse, in which the ship has swung with the tide to an extent where the two cables grow across each other. |
| ORDER OF SAILING | The disposition of a fleet of warships when sailing in company, or of a convoy. It is from the order of sailing that the order of battle is formed when an enemy fleet is sighted. |
| ORDINARY SEAMAN | The lowest man’s rating on board British ships. Boys are rated ordinary seamen and begin their man’s time on board at the age of 18, normally being rated able (A.B.) at the age of 21. The abbreviation is O.D., probably derived from OrDinary. |
| OROPESA SWEEP | A method of sweeping moored mines by a wire towed by a minesweeper: it required only one minesweeper to operate it. It swept mines to the side of the minesweeper by means of a long wire fitted with wire cutters placed at intervals along the wire to cut the mine moorings. The wire was towed astern of the minesweeper with a kite fitted to the wire a short distance from the point of tow to keep the wire down to a fixed depth below water. Near the end of the wire was an otter which forced it outwards as it was towed through the water, and at the end was a float to hold the wire at its fixed depth and prevent it sinking to the bottom. As the wire came into contact with the mine mooring wires, they slid along it until meeting a cutter, when the mooring wire was severed and the mine floated to the surface, where it could be destroyed or sunk by rifle fire. |
| OTTER | A board rigged with a line and bridle which, when towed underwater, stretches the line by reason of the outward angle at which the bridle holds it. It is used widely in fishing to spread out a net or to keep open the mouth of a trawl. (When otter boards are used on a trawl they are normally called doors.) The name comes from the otter board used by salmon fishers to tauten their line or net as they towed it along the shore, the otter being a great predator of salmon. |
| OUTHAUL | A line or purchase by which a sail is hauled outboard along a spar. Aboard a square rigged ship the studding-sails and their booms were hauled out along the yards by means of outhauls. On old-fashioned yachts with long bowsprits, the tack of the jib was hooked on to a traveler, a large iron ring running along the bowsprit, which was then hauled towards the outer (or crans iron) end of the bowsprit by the outhaul. |
| OUTRIGGER | (1) An extension to each side of the crosstrees of a sailing vessel to spread the backstays, in a schooner the topmast backstays, and in a full-rigged ship the topgallant and royal backstays.
(2) A counterpoising log of wood rigged out from the side of a native canoe in the Pacific and Indian Oceans to provide additional stability when carrying sail in a stiff breeze. (3) The projecting beams rigged on the sides of sailing men-of-war to which additional shrouds were led for extra support of the masts when the ship was careened. A great strain was exerted on the mast during careening as the ship was hauled down on to her side by tackles secured to the mastheads, hence the need for extra support by additional, temporary, shrouds. |
| OVER THE BAY | An expression used by the old seamen, particularly in the days of square rigged ships, to describe officers who had taken a few more nips of rum or whisky than necessary to ‘freshen their hawse’. |
| OVERFALL | A condition of the sea when it falls into breaking waves caused by wind or current over an irregular bottom, or by currents meeting. Tiderips and tide-races frequently cause over-falls. |
| OVERHAUL | (1) To increase the distance apart of the blocks of a tackle by running the rope back through the sheaves,
(2) The expression used to describe the action of a ship when she overtakes, or is catching up with, another ship at sea, (3) An expression sometimes used in connection with the inspection, testing, and repair of a vessel’s machinery, but the more correct nautical word in this respect is refit. |
| OVER-RAKED | A vessel is said to be over-raked when she is riding to her anchor(s) in bad weather and the seas break continuously over her bows. It is a condition which can often be ameliorated by increasing the scope of the cable through veering an extra amount so that the vessel may lie more easily. |
| OVERTAKING LIGHT | A white light displayed at the stern of a vessel under way at night, forming part of the compulsory navigation lights which a ship must burn under the regulations laid down by the International Convention for Preventing Collisions at Sea. The overtaking light, also widely known as a stern light, must have a visibility of two miles on a clear night and must show through an arc on either side of the vessel from right astern to two points abaft the beam. |
| OX-EYE | A name given to a small cloud which occasionally appears in the sky off the eastern coast of Africa and spreads quickly to cover the whole of the sky, presaging a severe storm accompanied by a violent wind. It gets its name from its resemblance, when first seen, to the eye of an ox. |
| OXTER PLATE | The name given to the outer plates of a ship’s hull which are riveted or welded to the stern post of a ship. |