| TERMS | MEANING: |
|---|---|
| A.B. | The abbreviated title for the rating of able seaman, a man able to perform all the duties of a seaman on board ship. In the old sailing ship days it was a man able to hand, reef, and steer, but today, to be an able seaman a man must have many more maritime skills than that. By some, the initials were thought to refer to an ‘able-bodied’ seaman but this is not the case; they are merely the first two letters of “able”. |
| ABACK | The situation of the sails of a squarerigged ship when the yards are trimmed to bring the wind to bear on their forward side. Sails are laid aback when this is done purposely to stop a ship’s way through the water or to assist her in tacking; they are taken aback when the ship is inadvertently brought to by an unexpected change of wind or by lack of attention by the helmsman. |
| ABAFT | Towards the stern of a ship, relative to some other object or position. Abaft the beam, any bearing or direction between the beam of a ship and her stern. |
| ABANDON SHIP | The order given when a ship is in danger of sinking or on fire for the entire crew to take to the boats and liferafts. |
| ABANDONMENT | A term used in marine insurance indicating the surrender of ship and cargo to the insurers in the case of a constructive total loss. |
| ABATEMENT OF FALSE LIGHTS | A right, under the authority of the Merchant Shipping Acts, by which the lighthouse authority in Britain may order the extinction or screening of any light visible to seaward which could be mistaken for that emanating from a lighthouse. |
| ABOARD | In or on board a ship. The word is also widely used in other maritime meanings; thus for one ship to fall aboard of another is for her to fall foul of another; in the days of sailing navies, to lay an enemy aboard was to sail alongside an enemy with the intention of carrying her by boarding: in square-rigged ships, to haul the tacks aboard was to brace the yards round for sailing close-hauled. |
| ABOVE-BOARD | Above the deck and therefore open and visible, which gave rise to the term used to denote open and fair dealing. |
| ABOX | An old sailing ship expression of the days of masts and yards. To lay the head-yards abox in a square-rigged sailing vessel was to lay them square to the foremast in order to heave-to. This brought the ship more under command if it was subsequently required to wear or to stay the vessel. But to brace abox is to brace the head-yards flat aback to the wind, not square to the mast, in order to ensure that the wind acts on the sails so that the bows of the ship cast the required way. |
| A-BRACKET | A position of a ship in relation to another or to a recognizable mark or place, being directly opposite to the ship. mark, or place. Thus when a vessel is abreast, say, a lightship, then the lightship is abeam of her. Line abreast, a naval fleet formation in which ships steam in position abeam of the flagship, forming a line at right angles to the course they are steering. |
| ACCOMMODATION PLAN | A naval architect’s set of drawings for the building of a new ship showing the layout below decks of cabins and berths for passengers, officers, and crew, together with the dining room, lounges, and other passenger spaces. The plan is normally drawn to a scale of 1 : 96 or 1 : 48 in feet (or 1:1 00 or 1:50 in metres) according to the size and complexity of the ship. Yacht designers usually term their accommodation drawing the General Arrangement plan, which shows in detail the principal features of the accommodation layout—berths, lockers, cupboards, toilet or shower, galley, navigator’s space, etc.—both in elevation and in plan. In addition there may be a number of cross sections, or half sections, showing the accommodation arrangement relative to the curving inside of the hull. This plan is normally drawn to a scale between 1:32 and 1:12 (or 1:30 and 1:10 in metres). |
| A COCKBILL | A term used to describe an anchor when it hangs by its ring at the cathead or from the hawsehole ready for letting go. In the case of stockless anchors which are let go from the hawsehole, a few feet of cable are veered so that the shank hangs clear vertically. |
| ACORN | The small ornamental piece of wood, usually in the shape of either an acorn or a cone, which was fixed on the top of the spindle on the masthead of a sailing vessel which carried the vane. Its purpose was to prevent the vane, which has a very loose-fitting sleeve, from being blown off the spindle. Although it was a standard fitting on all ships under sail, vanes are today rarely used even in those large sailing vessels still in commission, their place being taken by modern instruments to measure the strength and direction of the wind more accurately than ever could be done by means of a vane. |
| ACROSTOLIUM | The symbolical ornament, usually in the form of a shield or helmet, which ancient Greek or Roman ships carried on their prows either to seek favour with the sea gods or to ward off evil. It was the forerunner of the figurehead with which more modern ships were, and some still are, decorated. |
| ACTING | A prefix used in navies and merchant navies, as in other similar services, to denote that a higher rank is being temporarily held. Payment is, of course, at the full rate for the acting rank or rating. |
| ACTIVE LIST | The list of officers of a navy or a merchant navy who, as in all similar services, are actually serving or are liable to be called upon for active service at any time. Officers on the retired list may also be liable to recall to active service if below a certain age. |
| ACTUAIRE (French) | The list of officers of a navy or a merchant navy who, as in all similar services, are actually serving or are liable to be called upon for active service at any time. Officers on the retired list may also be liable to recall to active service if below a certain age. |
| ACTUAIRE (French) | An open transport for troops, propelled both by oars and sails, of the 18th and early 19th centuries. |
| ACTUAIROLE (French) | A small galley propelled by oars and used for the transport of troops up and down the coast in the 18th and early 19th centuries. |
| ACUMBA | Another term for oakum. It was originally the Anglo-Saxon word for the coarse part of flax, and thus received its association with oakum as a suitable material for the purpose of caulking a seam. |
| ADAMANT | An old name for the lodestone. In its true meaning it was the name for any very hard stone and became finally the name for a diamond. According to contemporary seamen there were two explanations to account for its connection with the lodestone, one that the Latin derivation of the word was ad-amare, to take a liking to, to have an attraction for, which suggested a lodestone or magnet; the other that it was the name of a mythical rock with magic properties, of which one was the power of attraction. The association of the name with a lodestone came to an end in the 17th century when it became totally associated with a diamond. |
| ADMIRAL | In all maritime nations the title of the commander of a fleet or of a subdivision of it. The word certainly comes from the Arabic word amir, prince or leader, and in the Mediterranean, as early as the 12th century, the leader of the Moslem fleets had the title amir-albahr. commander of the sea. The substantive amir and the article al were combined by other maritime nations in the Mediterranean as they developed to form the title amiral (French) and almirante (Spanish). The title reached Britain and other north European nations probably as a result of the Crusades, but became confused with the Roman admirabilis. As well as signifying the chief commander of the fleet, the title was also applied to his ship, and in many of the Elizabethan descriptions of voyages published in England the word almost invariably applied to the ship; the commander himself frequently being described as ‘general’ or ‘captain’, or a combination of the two. The four active ranks, or flag ranks as they are known, are admiral of the fleet, admiral, vice admiral, and rear admiral, in descending order. These ranks are found in most navies though in different forms and spellings. The exclusively male tenure of the rank of admiral was first breached in 1972 when the United States Navy promoted a lady. Miss Alene Duerk. to flag rank as head of the Navy Nurse Corps. |
| ADMIRAL OF THE FLEET | From the earliest days the senior admiral in the British Navy, whose presence at sea was originally signified by •the Royal Standard flown from the mainmast head, replaced at the end of the 17th century by the Union flag. The admiral of the fleet held his post until death. In 1693 he was paid £6 a day with no allowance for servants, but in 1700 his daily pay was reduced to £5 and he was allowed fifty servants for whom he drew £1,014 a year. Until 1863 the rank was held only by the senior admiral on the list although one or two special exceptions were made. Admiral Lord St. Vincent was made an additional admiral of the fleet in 1821 by King George IV because Lord Wellington had been made a field marshal by the army. And in 1830, to celebrate his accession to the throne, William IV, the ‘sailor king’, made two more admirals of the fleet. All these, however, lapsed on the death of the holders, reducing the number again to one. Between 1854 and 1857 there was no admiral of the fleet in the British Navy. The admiral on the top of the list by seniority, and therefore the one to be made admiral of the fleet, was Thomas Gosselin, but as he had not been to sea for forty-five years and was also mentally deranged, he was not considered fit for promotion to so exalted a rank. When he died in 1857 the next admiral in seniority, Sir Charles Ogle, was promoted. In 1863, the army now having six field marshals, it was decided to allow the navy three admirals of the fleet. In 1870 new regulations were introduced to the effect that admirals of the fleet should retire at the age of 70, leaving vacancies for three always on the active list. Promotions to this rank during and after the First World War (1914-18) increased the numbers both on the active and retired lists, and although they were reduced by deaths during the twenty years between the two world wars, the numbers were increased again as a result of promotions made during and after the Second World War. In 1940 all admirals of the fleet on the retired list were replaced on the active list in order to conform with the army practice in respect of field marshals, who never retired, and it was laid down that all future admirals of the fleet would remain on the active list for life. Equivalent ranks in other navies are fleet admiral (U.S.A.), Grossadmiral (Germany), and Grande Ammiraglio (Italy). |
| ADMIRAL’S CUP | A perpetual challenge award established in 1957 by the Royal Ocean Racing Club, London, for biennial international team racing for yachts originally limited to between 30 and 60 feet in waterline length. The ‘admiral’ in the title was Sir Myles Wyatt, who in 1957 was “admiral of the Royal Ocean Racing Club. The series of races consists of two inshore races of 30 miles each and the two offshore races, to include the Fastnet race, totalling some 830 miles. The limiting size of entrants was later modified to between 25 and 70 feet (7-6-21-3 m) R.O.R.C. rating. The cup was won by Great Britain the first year, by the Netherlands in 1959, by the U.S.A. in 1961, by Britain in 1963 and again in 1965, by Australia in 1967, by the U.S.A. in 1969, and was regained by Great Britain in 1971 by a team led by the then Prime Minister, the Rt. Hon. Edward Heath. The winner in 1973 was the West German team led by Hans-Otto Schumann. The Cup was again regained by Britain in 1975. The Admiral’s Cup is now recognized as the most important international competition in the ocean racing world. |
| ADMIRALTY | The generic international term for jurisdiction over maritime causes, with authority to establish courts presided over by a judge of Admiralty. It did not, in times past, indicate military command of naval forces, which would normally be specifically conferred by a sovereign or other ruler on an individual who was sometimes called captain-general until the term admiral came gradually to replace it during the late 13th and early 14th centuries. At the same time, in Britain, Admiralty came also to be applied to the office of the Lord High Admiral in its military and administrative aspects with regard to the Royal Navy, and the officials executing the office of the Lord High Admiral when that office was put into commission were known as Lords Commissioners of the Admiralty and their committee as the Board of Admiralty. This system continued in Britain until 1964 when the office of Admiralty was absorbed with those of the army and the air force into a Ministry of Defence. As a concession to long tradition those within the Ministry of Defence charged with the overall direction of naval affairs are collectively called the Admiralty Board but are no longer Lords Commissioners. In other maritime nations the overall direction of their naval affairs is usually conducted by a Ministry of Marine or a Navy Department. |
| ADORNINGS | A general name often used to describe the gingerbread work on the stern and quarter galleries of the old sailing ships, particularly naval, from about the 15th to the 19th centuries. |
| ADRIFT | A term denoting floating at random, as of a boat or ship broken away from her moorings and at the mercy of wind and waves. To cast adrift, of a ship, to abandon her at sea; of persons, to place them in a ship’s boat or raft and leave them. The word is also used to describe a seaman absent from his watch, or his work, or failing in his prompt and due return from leave. |
| ADVANCE | The amount of wages paid to a seaman when signing on for a new voyage. In the Royal Navy, before the introduction of continuous service, the advance was two months’ wages; in many merchant ships it was one month’s wages, the clearing off of which was known as ‘working off the dead horse’. |
| ADVANTAGE | The term used to describe the method of reeving a tackle in order to gain the maximum increase in power. The power increase in a tackle is equal, if friction is disregarded, to the number of parts of the fall at the moving block, and a tackle is rove to advantage when the hauling part of the fall leads from the moving block. Where a tackle is rigged so that the hauling part leads from the standing part, the power gained is less and the tackle is said to be rove to disadvantage. |
| ADVENTURE | A commercial term recognized in maritime law to denote consignments of cargo sent abroad in a ship to be sold or bartered by the master to best advantage, hence cargo carried without fixed destination but to be sold when opportunity offers. A bill of adventure, one signed by a merchant in which he takes the chances of the voyage. It is now obsolete except perhaps in remote parts of the world. In French maritime law a bill of gross adventure is an instrument making a loan on a maritime security. |
| ADVICE-BOAT | A small vessel used during the period of sailing navies to carry orders or dispatches to and from fleets and single ships at sea. They were of no particular size or rig. The only criterion of their employment being speed. |
| ADZE | Sometimes written as ADDES in old books on the shipbuilder’s art, the principal tool of the old-time shipbuilder in the days of wooden ships, resembling a garden mattock but with a longer and sharper blade slightly curved inwards towards the handle. It was always considered a most difficult tool to use, but with it an experienced shipbuilder could smooth, or ‘dub’, an oak plank and leave it as smooth as if it had been planed. An adze was also used extensively by coopers in making casks for the stowage of victuals, etc., at sea. |
| AERODYNAMICS | A branch of the science of pneumatics which deals with air and other gases in motion and with their mechanical effects. In its maritime connection aerodynamics can be used to explain how a wind produces forward motion in a sailing vessel even though it blows from before the vessel’s beam. When a wind strikes a surface, its force can be resolved into two components, one acting at right angles to the surface and the other along the surface. If this surface is the sail of a boat, the component blowing along the sail can be disregarded, as it is providing no force on the sail, but the component at right angles to the sail does exert a force. That component can now similarly be resolved into two more components, not in relation to the angle of the sail but to the fore and aft line of the boat. The larger of these two components exerts a force which tries to blow the boat directly to leeward, and the smaller of them, blowing along the fore and aft line, is all that is left of the wind to drive the boat forward. It is at this point that the keel of the boat, or the centreboard in the case of dinghies, comes into play. It provides a lateral grip on the water which offers considerable resistance to the larger component and very little resistance to the smaller, so that the boat moves forward and makes only a small amount of leeway. There is another element which gives forward movement to a sailing boat when the wind acts on her sail. In the resolution of forces considered above, the sail has been considered as a flat surface on which the wind strikes at an angle. In fact a sail has a parabolic curve fore and aft, of which the steepest part of the curve is at the luff. When an airstream meets a curve at an acute angle it creates a partial vacuum as it flows over the steepest part of the curve, and in a sailing boat this partial vacuum acts to pull her forward and reinforce the small component of the wind that is driving her forward. The greater the speed of the airflow over the steepest part of the curve, the more effective the partial vacuum, and so a modern sail design increases the speed of the airflow by creating a slot, or ‘funnel’, along the luff of the mainsail by setting a headsail forward of the mainsail. In cases where the clew of the headsail overlaps the luff of the mainsail the wind is funnelled with even greater speed over the steepest part of the curve and so increases even more the partial vacuum. When a sailing vessel is close-hauled, with the wind blowing over the bow, she can thus move forward against the direction of the wind, first because of the small component of the wind which gives her forward motion, secondly because of the partial vacuum caused by the wind flowing over the curve at her luff which pulls her forward, and thirdly because of her keel which provides effective lateral resistance to the larger component of the wind and prevents her being blown down to leeward at right angles to her desired course. |
| AFER | The old Latin name for the south-west wind, to be found in some of the old accounts of early voyages. |
| AFFLECK | The name of two brothers who both became admirals in the British Navy. EDMUND (1724-88) was captain of the Bedford, the first ship to sight the Spanish fleet during Lord Rodney’s relief of Gibraltar in 1780, resulting in the ‘moonlight battle’ in which Rodney heavily defeated de Langara’s ships. He was on the American station during the latter part of the War of American Independence (1775-82) and played a considerable part in the battle of the Saints in 1782, being made a baronet for his gallantry. He ended his naval service as rear admiral of the Blue and member of parliament for Colchester. His brother PHILIP (1726-99) was with Admiral Boscawen at the capture of Louisburg in 1758, served in American waters during the War of American Independence, and was commander-in-chief of the West Indies station from 1790 to 1793. On his return he was appointed a Lord Commissioner of the Admiralty until 1796 when he retired with the rank of admiral of the Blue. |
| AFFREIGHTMENT CONTRACT OF | The legal term to describe the contract between a shipowner and a merchant under which the former contracts to carry the goods of the latter to a certain destination on the payment of a sum of money known as the freight. The law which deals with contracts of affreightment is a branch of the general law of contracts. It should not be confused with a charter party, under which a ship is hired by a merchant to carry his goods and who then takes temporary possession and control of her, or with a bill of lading, which is the actual document signed by the master of a ship acknowledging the shipment of goods. |
| AFLOAT | The condition of a vessel when she is wholly supported by the water and clear of the ground. The word is also often used in a more general sense to mean at sea, or of life at sea. afloat support, a term used in navies to indicate the provision at sea of auxiliary and supply ships to enable a fleet of warships to replenish with essential stores, fuel, etc., to enable it to operate for long periods at sea without recourse to shore bases. |
| AFT | At or towards the stern or after part of a ship, as a word either of position or motion. A gun may be mounted aft (an expression of position) and seamen sent aft to man it (an expression of motion). Fore and aft, from stem to stern. It is a contraction of abaft, though used in a general, not a relative, sense. The adjective is after, e.g., the after part of a ship, as above. |
| AFTERBODY | That part of a ship’s hull which lies aft of the midship section. It embraces the whole of the after half of the hull from upper deck to keel, and on the designed shape of the afterbody depends the run of the ship. |
| AFTERGUARD | Seamen whose station in the days of sail was on the poop or quarterdeck to work the after gear of the ship. Also a term often used in yachting to denote the owner and his guests; in yacht racing, the helmsman and his advisers. |
| AFTERTURN | The twist given to rope, when the strands are laid up to form it, in the opposite direction to the twist of the strands. |
| AGAMEMNON | A ship’s name used five times in the British Navy. The first of the name, a 64-gun ship launched at Buckler’s Hard in 1781, had Horatio Nelson as her captain in 1793-4 in the Mediterranean and later saw a good deal of action including the battles of Copenhagen and Trafalgar before she was wrecked in the Rio de la Plata in June 1809. The next Agamemnon, launched at Woolwich in 1852, can claim to be the first large warship specifically designed from the start as a single-screw battleship as opposed to those which had an engine fitted in them after building. She assisted in the laying of the first Atlantic cable in 1858. |
| AGE OF THE MOON | The number of days that have elapsed since the day of new or change of the moon. A lunation, which is the interval between the times of successive new moons, is 29{ days, so that the age of the moon at first quarter is 7 days; at full moon, 15 days; and at third quarter, 22 days. |
| AGROUND | Said of a ship when she is resting on the bottom. When put there purposely, a ship takes the ground, when by accident, she runs aground, or is stranded. |
| AHEAD | A word {opposite to astern) used in two senses at sea. Referring to direction, it means any distance directly in front of a ship on her current heading; referring to movement, it means the passage of a ship through the water in the direction in which her bows are pointing. It is a word much associated with the orders to work the engines of a ship, the usual engine room telegraph having the words ‘ahead’, ‘astern’, and ‘stop’ printed on the dial with a manually operated pointer to indicate slow, half, and full speed ahead or astern. |
| AHOY! | The normal hail to a ship or boat to attract attention. |
| A-HULL or LYING A-HULL | The condition of a ship drifting under bare poles with her helm a-lee, or hove-to at sea under stress of weather. The term is also frequently applied to a ship which has been abandoned at sea. |
| AIRCRAFT CARRIERS | Major warships capable of operating aircraft. The idea of operating aircraft from the decks of warships originated very soon after the flying machine became a practical proposition. In 1911 the American aviator Eugene Ely both took off and alighted on platforms erected on cruisers. A few months later Commander Samson, of the British Navy, took off in a Short biplane from a similar platform on the forecastle of the battleship H.M.S. Africa. Though aircraft were regularly flown off numerous British warships during the First World War (1914-18) and, in 1 9 1 7, a Sopwith ‘Pup’ aircraft was landed on the flight deck superimposed on the forecastle of H.M.S. Furious, it was not until that ship had a landing deck built abaft her bridge superstructure that regular attempts to land on were made. These were in the main a failure and it was not until a ship with an unobstructed deck over her whole length was completed in 1918 that the problem of landing on was satisfactorily solved. This was H.M.S. Argus which dispensed with any superstructure or funnel by incorporating a hydraulically. raised and lowered bridge and by discharging her boiler smoke and gases over the stern. She was followed by H.M.S. Eagle in 1920, converted from an uncompleted battleship, which had a superstructure and funnels offset on the starboard side of an otherwise unobstructed flight deck, as did H.M.S. Hermes, completed three years later and the first ship to be built as a carrier from the keel up. These were known as ‘island’ carriers. The Furious emerged in her final form in 1925, a flush-deck carrier like the Argus. The U.S. and Japanese Navies had meanwhile commissioned their first small carriers in 1922, the Langley and Hosho respectively. These were flush-decked with funnels to one side which could be lowered horizontally during flying operations. No further carriers were built until after the conclusion of the Washington Treaty, when the U.S. and Japanese Navies each selected for conversion two capital ships due to be scrapped, the battle-cruisers Lexington and Saratoga for the former, the battle-cruiser Akagi and the battleship Kaga for the latter. These were all island carriers (i.e., carriers with the bridge structure offset to the side) of some 36,000 tons, though the superstructure in the Japanese ships was comparatively small as it did not incorporate the funnels which, instead, projected horizontally over the side, a feature common to the majority of their carriers. The British selected the smaller ships Courageous and Glorious, originally sister ships of the Furious, for conversion to island carriers. Subsequent carriers built for the three major navies, and the Beam, converted from a battleship by the French, adopted the island design which thenceforward became standard. From 1937, however, when the British laid down the first of their post-Washington Treaty carriers, H.M.S. Illustrious, British design differed from that of other navies in the incorporation of armoured flight decks and hangar sides. This greatly improved their resistance to bomb attack but reduced the number of aircraft they could operate. War experience bore out the necessity for such increased protection and both the Americans and the Japanese adopted it for fleet carriers laid down after the battle of Midway in 1942. Carriers built up to the end of the Second World War (1945) were of three main types — large fleet carriers operating up to 100 aircraft, light fleet carriers operating about 40, and escort carriers, ships of moderate speed and originally converted from merchant ships, to operate between 20 and 35 aircraft. None of the last type remain in service. The majority of light fleet carriers still in service have been relegated to auxiliary roles such as commando ships operating helicopters. Fleet carriers are now called attack carriers in the U.S. Navy, the only navy which still operates them in considerable numbers. The largest of these in existence is the U.S.S. Nimitz, displacing 95.000 tons and operating about 100 aircraft. She was commissioned in 1975 and has a crew of 5,700 officers and men. Like the U.S.S. Enterprise (75,700 tons) before her, she is nuclearpowered. Two more carriers in this class are planned, the Eisenhower, due to be launched in 1977, and the Vinson, 1980. |
| AIR-SEA RESCUE | A service introduced initially by the Royal Air Force in 1940 as a means of rescuing pilots and aircrew of aircraft ditched or shot down at sea as a result of enemy action. It was operated by high-speed launches based at a number of convenient points round the coastline of Britain, particularly along the Channel and North Sea coasts where the majority of air action took place. Inflatable dinghies carried in aircraft were fitted with automatic wireless transmitters on which the launches could home. Since the war, the development of the helicopter has revolutionized air-sea rescue, and many countries, including Britain, operate them as a life-saving service at sea in addition to the lifeboat services. |
| ALBURKAH | A small, iron, paddle-wheel steamer of 55 tons, designed by Macgregor Laird, which was the first iron ship to make an ocean voyage. In 1832 she left Liverpool for the Niger, with her designer on board, returning to Liverpool in 1834 with only nine of her original crew of forty-eight, the remainder having died of fever. |
| ALDIS LAMP | A hand-held electric lamp fitted with a finger-operated shutter used for the sending of signals at sea. |
| A-LEE | The position of the helm of a vessel when it has been pushed down to leeward in order to tack a sailing vessel or to bring her bows up into the wind, ‘helm’s a-lee’, the response of the helmsman after putting the helm down on the order to tack. When a vessel heaves-to under storm canvas in rough weather, the helm is lashed a-lee so that the bows are continuously forced up towards the wind, in which position the vessel lies more easily. |
| ALL HANDS | An order on board ship for the seamen of all watches to muster on deck immediately. It is an order usually given either in an emergency or for performing an evolution which requires the use of all available seamen. The full order is ‘all hands on deck’, but it is normally shortened to ‘all hands’. |
| ALL IN THE WIND | An expression used to describe the situation when a sailing vessel, while going about, is head to wind and all her sails are shivering. |
| ALL STANDING | A ship is said to be brought up all standing when she lets go her anchor with too much way on and so is brought suddenly to a stop as the anchor bites. In earlier sailing ship days, all standing was an expression sometimes used to denote that a ship was fully equipped. |
| ALL-A-TAUNT-O | The condition of a squarerigged sailing vessel where all the running rigging is hauled taut and belayed and all her yards are crossed on the masts, i.e., have not been sent down. In general it refers more to ships with very tall masts than to more rugged ships with shorter masts. |
| ALLEYWAY | The name usually given in merchant vessels to a passage-way along the decks below the upper deck, giving access to cabins or other parts of the ship. |
| ALLIANCE | A frigate of the Continental (U.S.) Navy, was built at Salisbury, Mass., and launched in April 1778. In 1779 she sailed for Brest from Boston, commanded by Pierre Landais. She was part of the squadron of John Paul Jones which sailed from France in August 1779 and was present at the action when the Bonhomme Richard captured H.M.S. Serapis off Flamborough Head on 23 September. In 1781, under the command of John Barry, she sailed from Boston with a member of President Washington’s staff on board to ask for the dispatch of-a French fleet to American waters to support the revolution. Later she made several minor captures and was used for escort purposes. She became the last remaining vessel of the Continental Navy and was sold on 1 August 1785. |
| ALOFT | Above, overhead, also anywhere about the upper yards, masts, and rigging of ships. ‘away aloft’, the command for topmen to take up their stations on the masts and yards. ‘gone aloft’, a sailor’s phrase for a seaman who has died. |
| ALOOF | An old expression meaning ‘keep your luff”, or sail as close to the wind as possible. Sometimes, in old books of voyages, written as ‘aluffe’. The expression was most often used when a ship was sailing along a lee shore, the order to ‘keep aloof meaning to keep the ship’s head nearer to the wind to prevent her being driven closer to the shore. ALOW the opposite to aloft, meaning on or near the deck of a ship. When a vessel is carrying all sail alow and aloft, she has all her sails, including studdingsails, set and all reefs shaken out. |
| ALTERNATING LIGHT | A navigational light displayed by a lighthouse, lightship, or lighted buoy in which two colours are shown alternately, with or without a period of darkness separating them. |
| ALTITUDE | From the Latin altitudo, height, the angle between the centre of a celestial body and the rational horizon as measured from the centre of the earth. It is one of the three sides of the astronomical triangle, through the solution of which a position line can be plotted on a chart. In the case of altitudes of stars, most of which are infinitely distant, the observer’s horizon can be accepted as the rational horizon without any loss of accuracy, but in an observation for navigational purposes of the sun or moon, which are both much closer to the earth, a correction, known as semi-diameter, must be applied to the observed altitude to allow for the distance between the centre of the sun or moon and their lower limb, which is the point of observation, and for the distance between the observer’s position on the earth’s surface and the centre of the earth, which is the point from which the true altitude must be measured for astronomical calculations. |
| ALTMARK | A German naval tanker of 8,053 tons, was tender to the pocket-battleship Admiral Graf Spee during the latter’s operations as a commerce raider in the South Atlantic during the Second World War. On her way back to Germany with 299 British prisoners on board after the Graf Spee had been sunk, she was intercepted on 16 February 1940 by the British destroyer Cossack in Jossing Fjord (Norwegian territorial waters), the prisoners rescued, and the ship left, as she was not then a warship. Later she became a supply ship for German surface raiders under the name of Uckermark and was accidentally destroyed at Yokohama on 30 November 1942. |
| AMAIN | An old maritime word meaning •immediately’, as ‘let go amain’, let go the anchor at once. Another old naval expression of the 15th and 16th centuries was ‘waving amajn’, which was a direction by a warship to a merchant vessel, encountered in the waters claimed by a sovereign state, to strike her topsails in salute. The actual waving was done with swords or pikes to indicate the warlike nature of the ship demanding the salute. In the same context, the merchant ship would ‘strike amain’, i.e.. let fall her topsails immediately. |
| AMBERGRIS | From the French ambre gris. grey amber, a light, inflammable fatty substance sometimes found in the intestines of sperm whales iPhyseteridae) or floating in tropical seas. It occurs in lumps from a few ounces to several hundred pounds and is used extensively in the preparation of perfumes. |
| AMIDSHIPS | In the middle of the ship, whether longitudinally or laterally. It is more usually known as a helm order, normally shortened to ‘midships, to centre the helm in the line of the keel. |
| AMPLITUDE | The angle between the point at which the sun rises and sets and the true east and west points of the horizon. In earlier days, amplitudes were used to find the variation of the compass, the difference of either the morning or evening amplitude from the mean giving the variation. This was first suggested by Francisco Faleiro in his Tractado de Esphera y del Arte del Marear, published in 1535. In 1595 Thomas Hariot produced a table of amplitudes which saved the navigator the trouble of working them out; it is published in the introduction to the Instructions for Raleigh’s Voyage to Guiana, now in the British Museum. This method of discovering the variation was liable to error because of the considerable refraction of the sun at sunrise and sunset. |
| ANCHOR | A large and heavy instrument designed to hold a ship in any desired locality and prevent her from drifting at the mercy of wind. tide, or current. This is achieved by her anchor, attached to the ship by a cable, digging itself into the sea bed and holding the ship fast. The earliest forms of anchor were large stones, or baskets filled with stones, and these were used by the ancient Greeks. As ships grew larger, more efficient anchors were required to hold them, and iron hooks, designed to dig themselves into the sea bed as any strain came upon them, were introduced. Their invention has been credited variously to King Midas of Phrygia and to the seamen of Tuscany. A second arm to the hook, making them double-headed, was added shortly afterwards, and the anchor thus took the general shape which we know today. An early improvement was the addition of a stock, or horizontal arm, at the top of the shank of the anchor and set at right-angles to the hooks, or flukes, the purpose being to ensure that the flukes lay vertically on the sea bed and thus dug themselves in to provide maximum holding power. This basic anchor, known as the fisherman’s anchor, with two flukes and the stock at rightangles, remained the standard pattern of anchor for centuries, but in the early part of the 19th century a further improvement was made by curving the arms, which provided added strength in a period when welding was still an imperfect art. A persistent drawback to this type of anchor was the difficulty of stowage, but this was obviated later in the century by the invention of the Martin close-stowing anchor, in which the stock was in the same plane as the arms, which themselves canted about a pivot in the crown of the anchor and thus forced the flukes downwards into the sea bed to provide holding power. These anchors were stowed flat on an anchor-bed when not in use. It was a short step from the closestowing to the stockless anchor, which had the advantages of making anchor beds unnecessary, of simplicity in working with a resulting saving of time and labour, and still greater ease of stowage. For smaller craft, such as yachts, a further development of the stockless anchor has resulted in simpler and more efficient designs, such as the CQR, or ploughshare (known in the U.S.A. as a plow anchor) and mushroom anchors and others similar in operation. While for their small size they provide better and more secure holding even than the stockless, they are unsuitable for seagoing ships of any size, since, when built large enough for this purpose, they present unacceptable problems of efficient stowage on board. But they are frequently used in cases where permanent anchoring is required, as in the case of lightships, oil rigs at sea, and moorings. The most modern development is an anchor with particularly deep flukes which pivot round a stock at the bottom of the shank. For big ships it is the Meon anchor, and for small vessels the Danforth. This development combines theadvanlages of both main types of anchor, as although it has a stock to turn the flukes into the ground, it can still be stowed in the hawsepipe like a stockless anchor. Efficiency factors of the different types of anchor have been worked out but are apt to be misleading as so much depends on the type of ground in which the anchor beds itself. In terms of resistance to drag, the CQR anchor is generally recognized as best, with the Danforth and Meon coming a close second. Least efficient is the fisherman’s anchor. |
| ANCHOR BUOY | A buoy used to mark the position of a ship’s anchor when it is on the bottom. With small anchors, such as those of yachts or fishing vessels, the buoy rope is usually attached to the crown of the anchor with a turn round one of the flukes so that it can be used to weigh the anchor if the flukes are caught in rocks or stones; in large anchors it is normally attached with a short length of rigging chain to the gravity band or the crown to avoid damage by chafing on the bottom. The length of the buoyrope is of course adjusted to the depth of water in which the anchor lies, allowing for the fact that the buoy must be able to watch (rise without tightening the rope) at high water. When using an anchor buoy it is always streamed before the anchor is let go to avoid any danger of the buoy rope becoming entangled with the cable and being dragged under water as the cable runs out. |
| ANCHOR LIGHT | Another name for a riding light. For details of all navigational lights. |
| ANCHOR WARP | The name given to a hawser or rope when it is attached to an anchor and used as a temporary cable. |
| ANCHOR WATCH | A precaution taken on board ship when lying to an anchor in bad weather with a danger of the anchor dragging. The watch normally consists of an officer on the ship’s bridge, who by frequent compass bearings of shore objects can detect whether an anchor is dragging, and a small party on the forecastle ready to watch and work the cable. A dragging anchor can often be detected by feeling vibration in the cable; another sign is when the cable slackens and tautens alternately in a marked manner. |
| ANCHORAGE | An area off the coast where the ground is suitable for ships to lie to an anchor, giving a good and secure holding. These areas are marked on a chart with the symbol of an anchor. In older days it was also the name given to a royal duty levied on vessels coming to a port or roadstead for shelter. |
| ANEMOMETER | An instrument for measuring the velocity of the wind. It consists of a number of wind-driven cups connected to a vertical spindle which, as it rotates, moves a pointer on a scale marked in knots or miles an hour. In large ships it is mounted in any position where the wind is not blanketed by part of the superstructure, frequently at the masthead; hand-held models are sometimes used in smaller vessels although they are rapidly becoming permanent fittings in many small sailing yachts. In another type of anemometer, known as a ventimeter, the wind enters the bottom of a glass cylinder and pushes a disc up a vertical rod against the force of gravity, the wind strengths being marked up the side of the cylinder and indicated by the height reached by the disc. Of the two types, the wind-cup model is the more accurate and reliable. |
| AN-END | A wooden mast is said to be an-end when it is cracked perpendicularly to the plane of the deck, or in the case of a topmast, to the plane of the top. The expression is virtually obsolete as few vessels, even the smallest, have wooden masts today. |
| ANGEL-SHOT | Another name used during the days of sailing navies for chain shot, in which a cannon-ball was cut into two and the halves joined by a short length of chain. When fired from a cannon, the force of discharge caused the shot to rotate at great speed so that it cut a swathe through whatever it hit. It was designed for use against the rigging of enemy ships, but was also employed as an anti-personnel weapon against men working on the upper deck. It was no doubt in this role that it obtained its second name through its ability to send many men to join the angels at a single discharge. |
| ANGLE OF CUT | In navigation, the smaller angle at which two position lines on a chart intersect. The reliability of a fix obtained by intersecting position lines depends on the angle of cut. When fixing a ship’s position by cross bearings of two marks, the prudent navigator aims to select marks whose bearings differ by not less than about 30°, recognizing that the nearer is the difference of bearings to 90°, and other factors being equal, the more reliable will be the resulting fix. |
| ANSWERING PENDANT | A red and white vertically striped pendant hoisted when answering a flag signal at sea to indicate that it has been understood. Until the signal has been fully understood, the answering pendant is hoisted at the dip, i.e., only half way up the signal halyards. The same pendant is used both in the naval signal code and in the International Code of Signals for merchant ships. |
| ANTARCTIC | A wooden sealer of 226 tons built in Norway in 187 1 as the Cap Nor. She was used on Henrik J. Bull’s Norwegian Antarctic expedition of 1894-5 and later employed on Otto Nordenskjold’s Swedish Antarctic expedition of 1901-3 when she was crushed and lost in the pack ice of the Weddell Sea in February 1903. |
| ANTARCTIC CONVERGENCE | A boundary in the southern oceans along which cold, poorly saline Antarctic surface water, flowing north from Antarctica, sinks beneath warmer southward-flowing sub-Antarctic water. The zone in which this takes place lies in about lat. 50° S. across most of the Atlantic and Indian Ocean sectors and is located between latitudes 55° and 62° in the Pacific sector. It is accompanied by a fall in surface temperature from about 5° C to 3° C in summer and from 3° C to 1° C in winter. The Antarctic convergence marks not only a change in the ocean’s surface temperature but also a change in chemical composition. There are also marked biological differences on either side of the convergence both with respect to life in the ocean and to bird life. Finally, the convergence influences the climatic characteristics of various sub-Antarctic islands whose shores are washed by its cold upwelling waters. |
| ANTI AIRCRAFT (A/A) CRUISER | A small and obsolescent cruiser with some of her mainarmament guns removed and replaced with highangle anti-aircraft batteries, used in the British Navy during the early years of the Second World War. Their function when thus converted was the defence of other ships from attack by aircraft. About eight of these cruisers, drawn from the 4.200-ton ‘C’-class cruisers of 1917-19, served with the British fleets during the Second World War. With the rapid growth in sophistication of aircraft attack during the war, particularly in the sphere of rocket armament and consequent lowlevel attack, these cruisers became no longer viable in their anti-aircraft role and were gradually phased out of service from 1942 onwards. |
| ANTICYCLONE | An area of high barometric pressure around which the wind circulates in a clockwise direction in the northern hemisphere and anti-clockwise in the southern. Anticyclones are always fair-weather systems, usually slow moving, and with the strength of the wind never more than moderate. |
| ANTIFOULING PAINT | A composition which includes poisons, usually based on copper or mercury, applied to the bottoms and sides, below the waterline, of all vessels to inhibit the growth of weed and barnacles and, in the case of wooden vessels, attack by worm such as the teredo. The paint forms a toxic solution in the water immediately around the vessel and is so mixed that the release of the poisons is gradual, lasting as long as the paint itself. |
| ANTI-GALLICANS | A pair of additional backstays temporarily rigged to provide extra support to the masts of square-rigged ships when running before the trade winds. They were used only in merchant ships, as men-of-war were always more heavily stayed than merchant vessels and did not, in the general run of naval service, spend days on end running a fixed course before a following trade wind. It was this continuous strain, often lasting for many days and always in the same direction, which made additional support for the masts desirable. The origin of the term is obscure; certainly it had nothing to do with the French, as the name might suggest. |
| ANTI-GUGGLER | A straw or tube feloniously entered into a cask or bottle to suck out the contents. It was a popular and relatively easy access to extra nourishment in hot climates during the 1 8th and 1 9th centuries when captains of ships often put their private stocks of wine and spirits in a hanging safe outside their cabins to keep them cool. Modern cooling methods have effectively removed this method of succumbing to temptation. |
| APEAK | The position of the anchor when the bows of a ship have been drawn directly above it during weighing, just before it is broken out of the ground. Originally the spelling was peek. |
| APOSTLES | The name given to the two large bollards, fixed to the main deck near the bows in the larger square-rigged sailing vessels, around which hawsers or anchor cables were belayed. In all the larger sailing vessels the anchor cables were brought inboard through the hawseholes on the main deck level since it was on that deck that the main capstan was mounted. In some of the smaller merchant ships of the sailing era, where the anchor cables were brought in over the forecastle deck, the knightheads, which supported the heel of the bowsprit, were used as apostles when belaying the anchor cables. |
| APPARENT WIND | The direction of the wind as it appears to those on board a sailing vessel. It differs from the true wind in speed and direction by an amount which can be worked out by a vector diagram: the vessel’s speed through the water being represented by one leg of a triangle of which the true wind and the apparent wind form the other two sides. The difference between the apparent and true wind is most pronounced when the true wind blows from directly abeam, and is reduced as the vessel sails closer to, or further off, the true wind. It disappears completely with the wind from dead astern. It is to the apparent wind, not the true wind, that a sailing vessel trims her sails. In the diagram the strength of the wind has been taken as 12 knots and the speed of the vessel as four knots. |
| APRON | (1) A strengthening timber behind the lower part of the stem and above the foremost end of the keel of a wooden ship. It takes the fastenings of the fore-hoods or planking of the bow, and was also sometimes known as a stomach-piece.
(2) Apron of a gun, a piece of lead sheet which was laid over the touch-hole to protect the vent from damp. (3) Apron of a dock, the platform rising where the gates are closed and on which the si 11 is fastened. |
| AQUALUNG | A device invented in France in 1943 by Captain Jacques-Yves Cousteau and Emile Gagnan to enable a diver to operate under water independently of an air supply from the surface. It consists of three small cylinders secured on the back of the diver, filled with air compressed to a very high pressure and connected to an air regulator. Two tubes are led from the air regulator to a mouthpiece, and air is supplied to the mouthpiece by the regulator at the pressure exerted by the depth of water reached by the diver. Nose and eyes are enclosed in a rubber mask fitted with a glass front, and the diving dress is completed with rubber foot fins or flippers. The safe depth to which a free diver wearing an aqualung can operate is about 100 feet, though experienced divers have operated successfully at depths greater than this. |
| ARGO | According to legend the ship in which the Argonauts sailed from Greece in search of the Golden Fleece. She was, in the Greek mythological story, built by Argos, the son of Phrixus and a famous shipbuilder of his time, of pines cut from Mount Pelion, supposed to have the property of never rotting. She was pierced for fifty oars, one for each of the fifty Greek heroes who manned her, and so perhaps would qualify to be considered as the first longship ever to sail the seas. It was recorded that the construction of the ship was supervised by the goddess Athena, who inserted a piece of the holy oak from Dodona into the prow so that the ship would never lose her way. Her bows were painted vermilion. At the time of her building the Argo was said to be the largest ship in the world. Perhaps the best-known modern version of the old story is that by Charles Kingsley in his book The Heroes (1856). |
| ARMILLARY SPHERE | A skeleton model of the celestial sphere, generally with the earth in the centre, showing the equator, poles, tropics, zodiac, etc., on the outer ring, with inner rings for the sun, moon, and planets. It was an instrument dating from the late 14th or early 15th century, designed to give the navigator a knowledge of the arrangement and motions of the heavenly bodies. It is recorded that a brass armillary sphere, costing £4.7s.6gL was supplied to Martin Frobisher for his first expedition in search of the North-West passage in 1576. |
| ARMSTRONG PATENT | A slang expression used in the big trading sailing ships around the end of the 1 9th and beginning of the 20th centuries to indicate that a ship was not fitted with any mechanical aids, and that all the work of the ship had to be done by human (crew) labour—in fact by their strong arms. |
| ARTEMON | The name given to a small square sail set on a yard and carried below a sharply steeved spar over the bows of Roman merchant vessels from about 200 b.c. to the decline of Roman shipping at the fall of the empire. Its function was largely as an aid to steering, while its spar or mast could be described as the forerunner of the bowsprit. It was virtually identical with the spritsail of the 14th- 17th centuries a.d. The name was also used, somewhat loosely and erroneously, to describe the mainsail of ancient ships. |
| ARTEMON MAST | Originally a sprit or mast set up in the bows of many ships of the 12th to 15th centuries, before the introduction of the bowsprit, as an aid to steering the vessel by stopping the bows coming up into the wind, a natural result of carrying insufficient canvas forward of the mast. Oddly enough, the French word for mizen is artimon. and the mizen-mast is mat d’artimon, which is of course at the other end of the ship. It is from the French word, and not the original, that in later ships built with four or five masts during the 19th and early 20th centuries, the fourth mast was sometimes known as an artemon mast. |
| ARTICLES | The conditions of service which are signed by a seaman in the merchant service when joining a ship. They are also signed by the master of the ship concerned and form a legal contract binding on both sides. Normally a ship’s articles embody provisions governing rates of pay, scale of victuals, daily hours of work, etc., and in older days when the route round Cape Horn was the only way to reach the Pacific Ocean from the Atlantic and was widely used as a normal trade route, they specified the extremes of latitude beyond which a seaman was not to be called upon to serve. In many ships’ articles a clause is usually included that in danger or distress the master may call on the seaman for exertions beyond the limitations expressed in the articles. Ship’s discipline on board is based on the articles, and the master has authority to punish members of the crew who transgress the articles. |
| ARTIFICIAL HORIZON | An aid to taking an astronomical sight with a sextant when the sea horizon is obscured through haze, fog, or darkness. The problem was recognized by navigators long ago, and many attempts have been made to remedy it. John Hadley, inventor of the reflecting quadrant, was the first, using a simple spirit level attached to the frame of the quadrant, but neither this nor a more sophisticated bubble horizon designed by John Elton in 1732 proved successful. An interesting suggestion was made by Serson, and later by the celebrated engineer John Smeaton, for a spinning top with a polished upper surface which by means of its gyroscopic inertia would provide a horizontal reflecting surface for use as an artificial horizon. The difficulty of applying such a solution to the deck of a ship at sea was, how ever, immense. In 1838 Lieutenant A. B. Becher R.N. invented an artificial horizon which consisted of a small pendulum with its bob suspended, for damping purposes, in a cistern of oil. This arrangement was fitted in line with the optical axis of the sextant telescope, and a slip of metal of which the upper edge was fixed at right angles to the pendulum, served as a horizon to which the observed celestial body was brought into coincidence. Many other attempts have been made to produce a satisfactory artificial horizon, including those by Admirals Beechey and Fleurais, but none was really practical at sea. The most successful has been the Booth bubble horizon which was designed specifically for air navigation and has since been adapted for use at sea. The problem of providing an artificial horizon ashore is simply solved by the use of liquid, usually mercury, introduced by George Adams in 1738. The use of liquid on board ship, however, is useless, as the slightest movement of the ship causes tremors to form on the surface of the liquid and thus break the desired horizon. |
| ASDIC | The original name of the underwater sound-ranging apparatus for determining the range and bearing of a submerged submarine. The name was derived from the initial letters of the Anti-Submarine Detection Investigation Committee, which was set up as an Anglo-French project in 1918, immediately after the First World War (1914-18). The invention was mainly French in conception. It is now known as sonar. |
| ASHORE | Aground, on the land, as opposed to aboard. A sailor goes ashore when he disembarks from a ship or boat and steps on land, either on duty or for a spell of leave. A ship runs ashore when she strikes the land, but runs aground if she strikes a submerged bank not connected with the shore, ‘a run ashore’, the seaman’s name for a short period of liberty. |
| ASPECT RATIO | The ratio between the length of the luff and the foot of a yacht’s mainsail. Whereas in the early days of the so-called Bermudian or Marconi mainsails the aspect ratio used to be as low as 2 : 1, in modern class racing yachts the luff-to-foot length ratio is generally between 3-5:1 and 4-0:1. Such a high aspect ratio means a tall and narrow sail which is like a glider’s wing set up on end. It is highly efficient in sailing very close to the wind (as near as 34-points or about 39°) as there is negligible twist in the surface of the sail from foot to head, whereas the old broader mainsails suffered from a pronounced sag to leeward. To make up for the loss of driving power of these small modern mainsails, very large headsails, often of more than twice the area of the mainsail, must be carried under certain conditions. |
| ASSISTANCE | A vessel of 423 tons built of teak at Calcutta in 1835 and originally named Baboo. She was purchased by the British Admiralty in 1848 and commissioned as a two-gun barque by Captain (later Admiral) H. T. Austin for a polar expedition in search of Sir John Franklin in 1850. She was also part of the squadron under Captain Sir Edward Belcher which sailed on a similar mission in 1852, but was abandoned by him in the ice in 1854. |
| ASTERN | Backwards, behind. It is a word employed in two senses in maritime use; in movement, that of a ship going backwards; in direction, directly behind a ship. As an order given to the engine-room of a ship for the movement of her engines, it indicates that they must be made to revolve in the reverse direction. |
| ASTROLABE | From the Greek astrer, star, and labin, to take. The word astrolabe has been employed for a variety of instruments used for solving astronomical problems relating to the sun, moon, and stars. A spherical astrolabe, often called an armillary sphere, consists of a series of concentric rings each representing one of the principal great circles of the celestial sphere. Equatorial armillaries were designed for determining declination of a celestial body, whereas zodiacal armillaries served to ascertain a heavenly body’s celestial latitude and celestial longitude, without having to resort to tedious computations. Planispheric astrolabes, which were perfected by the astronomers of India, Persia, and Arabia during the 7th century a.d., were complex instruments employing brass plates on which were engraved stereographic projections of the celestial sphere, each for a particular latitude of the observer, used essentially for time-measuring by solar observations during the day and observations of one of a small number of stars by night. The seaman’s astrolabe, unlike the complex astronomer’s instrument of the same name, is a very simple device used not for time-measuring but for measuring the altitude of sun or star. It consists of a massive graduated ring of brass fitted with an alidade, or sighting rule, pivoted at the centre of the ring. The instrument was suspended by the thumb or by means of a thread from a shackle at the top of the ring so that it hung vertically. The alidade was then turned about its axis so that the sun or star could be sightedalong it and the altitude read off on the ring. According to Ramond Lull, the famous Majorcan astronomer, the seaman’s astrolabe was in use among the pilots of Majorca as early as 1295. but Samuel Purchas informs us that Martin Behaim was the first to adapt the astrolabe to navigation in 1484. The seaman’s astrolabe, like the seaman’s quadrant, was of little use for observations from the heaving deck of a lively ship at sea. For fixing the approximate latitudes of new discoveries, however, in which observations were made ashore, it was an instrument simple in principle and use and well-adapted to the explorer’s needs. |
| ATHWART | A direction across the line of a ship’s course, athwart-hawse, the position of a ship or other vessel driven by wind or tide across the stem of another, athwartships, from one side of the ship to the other. athwart the tide, the position of a ship held by the force of the wind lying across the direction of the tide when at anchor. |
| ATLANTIC NEPTUNE | A magnificent collection of charts of the eastern coast of North America issued by the British Admiralty for the use of the Royal Navy in 1777 from surveys made by J. F. W., Des Barres, and others. Samuel Holland was the other chief surveyor engaged, and was in fact responsible for more of the surveys than Des Barres. but the series is made especially notable by the quality and beauty of the aquatints of views of ports and the coastline which were contributed by Des Barres. The word Neptune in the title was frequently used during the 18th century to describe collections of maps and charts, in much the same way as Atlas. |
| A-TRIP | An anchor is said to be atrip at the moment of weighing when it is broken out of the ground by the pull of the cable. In squarerigged ships topsails are atrip when they are hoisted to their full extent and ready for sheeting home and yards are atrip when they are swayed up and their stops cut ready for crossing. A topmast or topgallant mast is atrip when the fid is loosened ready for it to be struck, or lowered. |
| AURORA | A display of atmospheric lights visible in high latitudes, Borealis in northern latitudes and Australis in southern. They are caused by electrical discharges in the atmosphere, and when the displays are particularly bright, and movement of the light rapid, are almost invariably accompanied by severe electrical storms. There is also evidence that the frequency of display is generally similar to that of sun-spot activity, that in years of many sunspots there are more auroras than usual. Although the frequency of display varies from year to year, the largest number of displays in any year generally occur during the period of the equinoxes (March and September). Auroras take many forms, that of the corona being generally accepted as the most spectacular, although auroral curtains and bands are also magnificent spectacles. As the distance from the Arctic and Antarctic circles increase, the visible auroras generally take the form of the less exciting arcs and rays, while further away still the most frequent form is the diffused aurora. |
| AUSTER | The old Latin name for the south wind, used in some of the accounts of very early voyages. It was this meaning of south or southerly which gave the name Terra Australis to the vast land mass which early geographers believed must exist in the southern hemisphere to balance the land mass which was known to exist in the northern hemisphere. |
| AUTOMATIC HELMSMAN | A device fitted in many ships by which they are held on any desired course without the need of a man on the steering wheel. Any variation from the set course automatically supplies power to the steering engine so that the helm is put over and the vessel brought back to her course. In most systems the automatic helmsman is actuated by a gyroscopic compass so that the course steered is a true course. |
| AUXILIARY | (1) The name by which an engine is known when fitted for occasional use in a sailing yacht.
(2) Machinery fitted in steam and motor vessels which is not a part of the main propelling machinery but used for ancillary purposes, such as pumps, capstan engines, air compressors, etc. |
| AVAST | The order in any seamanship operation to stop or hold. It is generally thought to have been derived from the Italian basta, enough. |
| AWASH | The situation of an object almost submerged, as when seas wash over a wreck or shoal, or when a ship lies so low in the water that the seas wash over her. A falling tide which exposes a rock or bank which is submerged at high water makes it awash. |
| A-WEIGH or AWEIGH | The situation of the anchor at the moment it is broken out of the ground when being weighed. When the anchor is a-weigh the ship is no longer secured to the ground and will drift unless under sail or power. |
| AWNING | (1) A canvas canopy spread over a deck for protection from the sun. It is spread over a ridge rope in the centre line of the ship and secured to stanchions erected for the purpose on either side of the deck. In small yachts, a sail spread across the boom is often used for an awning.
(2) In the older sailing vessels that part of the poop deck which used to project beyond the doors of the poop cabins to form a shelter for the steering-wheel and binnacle was also called the awning. |
| AXLE-TREES | (1) The name given to the two cross-pieces of a wooden gun carriage fixed under the fore and after parts of the cheeks and carrying the spindles of the wheels.
(2) The iron spindle of the old-fashioned chain-pump used for pumping out the bilges of ships was also known as an axle-tree. |
| AYE AYE, SIR | The correct and seamanlike reply on board ship on receipt of an order. ‘Ayeaye’ is also the reply in the Royal Navy from a boat which has a commissioned officer below the rank of captain on board, when hailed from a ship. If no commissioned officer is on board, the reply is ‘No No’; if a captain is on board the reply is the name of his ship, and if an admiral, the reply is ‘flag’. Boats are hailed in this fashion so that watchkeepers on board ship may know the form of salute required when officers arrive on board. |
| AZIMUTH | From the Arabic as sumat, way or direction, a navigational term used to indicate the bearing of a celestial body. Its navigational definition is the measure of the arc of the horizon that lies between the elevated pole (north in northern hemisphere, south in southern) and the point where the celestial great circle passing through the celestial body cuts the horizon. It can be measured by a ship’s compass or, more usually, obtained from tables in the Nautical Almanac. It is a vital factor in fixing a ship’s position by astronomical navigation since it is along the azimuth of the celestial body that the intercept obtained from an observation is laid off on a chart to obtain a position line. Azimuths are also frequently used as a means of checking the deviation of a magnetic compass, the difference between the compass azimuth and the true azimuth as obtained from the Nautical Almanac giving the compass deviation for the course on which the ship is sailing. |