I. The third class of rating on Lloyd's books, for the comparative excellence of merchant ships. (See A.)

ICE-ANCHOR. A bar of round iron tapered to a point, and bent as a pot-hook; a hole is cut in the ice, the point entered, and the hawser bent to the shorter hook; by this vessels ride safely till any motion of the ice capsizes it, and then it is hauled in. The ice is usually entered by a lance, which cuts its hole easily.

ICE-BEAMS. Strengtheners for whalers. (See Fortifying.)

ICEBERG. An insulated mountain of ice, whether on Arctic lands or floating in the sea. Some have been known to be aground in 120 fathoms water, and rise to the height of 150 feet above it. Cook's obtaining fresh water from floating icebergs was not a new discovery. The Hudson's Bay ships had long made use of it; and in July, 1585, Captain Davis met with ice "which melted into very good fresh water."

ICE-BIRDS. Small sea-fowl in the polar regions.

ICE-BLINK. A streak or stratum of lucid whiteness which appears over the ice in that part of the atmosphere adjoining the horizon, and proceeds from an extensive aggregation of ice reflecting the rays of light into the circumambient air.

ICE-BOAT. A peculiar track-schuyt for the Dutch canals in winter.

ICE-BOUND. A vessel so surrounded by ice as to be prevented from proceeding on her voyage.

ICE-CHISEL. A large socket-chisel into which a pole is inserted, used to cut holes in the ice.

ICE-CLAWS. A flat claw with two prongs spread like a can-hook; the same as a single span or claw-dog.

ICE-FENDERS. Fenders of any kind, used to protect a vessel from injury by ice; usually broken spars hanging vertically where the strain is expected.

ICE LANE or Vein. A narrow temporary channel of water in the packs or other large collections of ice.

ICE-MASTER. A pilot, or man of experience, for the Arctic Sea.

ICE-PLANK. See Spike-plank.

ICE-QUAKE. The rending crash which accompanies the breaking of floes of ice.

ICE-SAW. A huge saw for cutting through ice; it is made of 2⁄8 to 3⁄8 inch plates of iron, and varies in length from 10 to 24 feet.

ICE-SLUDGE. Small comminuted ice, or bay-ice broken up by the wind.

ICE-TONGUE. See Tongue.

ICHNOGRAPHY. A ground plot or plan of a fortification, showing the details of the construction as if cut horizontally through.

ICK. An Erse or Manx term for a creek or gullet.

IDLER. A general designation for all those on board a ship-of-war, who,[399] from being liable to constant day duty, are not subjected to keep the night-watch, but must go on deck if all hands are called during the night. Surgeons, marine-officers, paymasters, and the civil department, are also thus denominated.

IDOLEERS. The name by which the Dutch authorities are known in their oriental colonies, the designation being a corruption of edle herren.

IGNORANCE. If a loss happen through the ignorance of the master of a ship, it is not considered as a peril of the sea; consequently the assurers are not liable. Nor is his ignorance of admiralty-law admissible as an excuse.

IGUANA. A large lizard used for food in tropical climates.

ILAND. The Saxon ealand (See Island.)

ILDE, and Ile. Archaic terms for island.

ILET. Lacing holes. (See Eyelet-holes.)

ILLEGAL VOYAGE. (See Voyage.)

IMMER. A water-fowl (See Ember-goose). The Colymbus immer of Linn., the great plunger of Buffon.

IMMERSION. The prismatic solid carried under water on the lee-side of a ship by its inclination.—Centre of immersion, the mean centre of the part immersed. (See Centre of Cavity.) Astronomically, immersion means the disappearance of a heavenly body when undergoing eclipse.

IMP. One length of twisted hair in a fishing-line.

IMPEDIMENTA. The ancient term for the baggage of an army.

IMPORT, Importation, and Importer, being exactly the reverse of export, exportation, and exporter, refer to those terms, and take the opposite meaning. To import is therefore to bring commodities into a country for the purpose of traffic.

IMPOSSIBLE. A hateful word, generally supplanted among good seamen by "we'll try." A thing which is impossible in law, is pronounced to be all one with a thing impossible in nature.

IMPOST. The tax received for such foreign merchandises as are brought into any haven within a prince's dominions.

IMPREGNABLE. Said of a fortress or position supposed to be proof against any attack.

IMPRESS, To. To compel to serve.

IMPRESSION. The effect produced upon any ship, place, or body of troops, by a hostile attack.

IMPRESSMENT. The system and act of pressing seamen, and compelling them—under plea of state necessity—to serve in our men-of-war.

IMPREST. Charge on the pay of an officer.

IMPREST-MONEY. That paid on the enlistment of soldiers.

IN. The state of any sails in a ship when they are furled or stowed, in opposition to out, which implies that they are set, or extended to assist the ship's course. Hence, in is also used as an order to shorten sail, as "In topgallant-sails." It was moreover an old word for embanking and inclosing; thus Sir Nicholas L'Estrange (Harleian[400] MS. 6395) speaks of him who had "the patent for inning the salt marshes."

IN AND OUT. A term sometimes used for the scantling of timbers, the moulding way, and particularly for those bolts that are driven into the hanging and lodging knees, drawn through the ship's sides, and termed in-and-out bolts.

IN-BOARD. Within the ship; the opposite of out-board.

IN-BOATS! The order to hoist the boats in-board.

IN-BOW! The order to the bowman to throw in his oar, and prepare his boat-hook, previous to getting alongside.

INCH. The smallest lineal measure to which a name is given; but it has many subdivisions. Also, a general name for a small coast islet on the northern shores, from the old Gaelic word.

INCIDENCE, Angle of. That which the direction of a ray of light, &c., makes at the point where it strikes with a line drawn perpendicularly to the surface of that body.

INCLINATION. In geometry, is the mutual tendency of two lines or planes towards each other, so as to form an angle.

INCLINATION OF AN ORBIT. The angle which the path of a comet or planet makes with the plane of the ecliptic.

INCLINATORY NEEDLE. An old term for the dipping-needle (which see).

INCLINOMETER. An invention by Wales in Cook's second voyage, where particulars are given.

INCOMPETENCY, or Insufficiency, of a Merchantman's Crew. A bar to any claim on warrantry; as it is an implied condition in the sea-worthiness of a ship, that at sailing she must have a master of competent skill, and a crew sufficient to navigate her on the voyage.

INDEMNIFICATION. A stipulated compensation for damage done.

INDEMNITY. Amnesty; security against punishment.

INDENTED LINE. In fortification, a connected line of works composed of faces which offer a continued series of alternate salient and re-entering angles. It is conveniently applied on the banks of a river entering a town, and was to be seen on the James river in Virginia, near Richmond, in 1864.

INDENTED PARAPET. One of which the interior slope is indented with a series of vertical cavities, enabling the men stationed within them to fire across the proper front.

INDENTING FOR STORES. An indispensable duty to show that every article has been actually received.

INDENTURES, Pair of. A term for charter-party.

INDEX. The flat bar which carries the nonius scale and index-glass of a quadrant, octant, quintant, or sextant.

INDEX-ERROR. The reading of the verniers of the above-named instruments. It is the correction to be applied to the + or - reading of a vernier when the horizon and index-glasses are parallel.[401]

INDEX-GLASS. A plane speculum, or mirror of quick-silvered glass, which moves with the index, and is designed to reflect the image of the sun or other object upon the horizon glass, whence it is again reflected to the eye of the observer.

INDEX-ROD. A graduated indicator.

INDIAMAN. A term occasionally applied to any ship in the East India trade, but in strict parlance the large ships formerly officered by the East India Company for that trade, and generally armed.

INDIAN INK. Properly Chinese; compounded of a peculiar lamp-black and gum.

INDIAN OCEAN. The great Oriental Ocean.

INDRAUGHT. A particular flowing of the ocean towards any contracting part of a coast or coasts, as that which sets from the Atlantic into the Straits of Gibraltar, and on other coasts of Europe and Africa. It usually applies to a strong current, apt to engender a sort of vortex.

INDUCED MAGNETISM. The magnetic action of the earth, whereby every particle of soft iron in certain positions is converted into a magnet.

INDULTO. The duty formerly exacted by the crown of Spain upon colonial commodities.

INEQUALITY, Secular. A small irregularity in the motions of planets, which becomes important only after a long lapse of years. The great inequality of Jupiter and Saturn is a variation of their orbital positions, caused by the disturbing action of one planet on the other.

INERTIA. The passive principle by which bodies persist in a state of motion or rest, and resist as much as they are resisted. (See Vis Inertiæ.)

INFANTRY. Foot soldiers of the regular army; so called throughout Europe after the original Spanish "infanteria," or troops of the infanta or queen of Spain, who first developed on a large scale the importance of the arm.

INFERIOR CONJUNCTION. Mercury or Venus is said to be in inferior conjunction, when it is situated in the same longitude as the sun, and between that luminary and the earth.

INFERIOR PLANETS. This name, the opposite of superior, is applied to Mercury and Venus, because they revolve in orbits interior to the earth's path.

INFORMATION. In admiralty courts, implies a clause introduced into a citation, intimating that in the event of a party cited not appearing, the court will proceed in his absence.

INGS. An old word said to be left here by the Danes; it signifies low grounds or springy meadows near a river, or creek, liable to occasional overflowings.

IN-HAULER. The rope used for hauling in the clue of a boom-sail, or jib-traveller: it is the reverse of out-hauler.

INITIAL VELOCITY. The velocity of a projectile at the moment of discharge from a gun.

INJECTION-PIPE. This is fixed in the interior of a marine steam-engine,[402] is fitted with a cock, and communicates with the water outside: it is for the purpose of playing into the condenser while the engine is working, and creating a vacuum.

INLAND SEA. Mediterranean. Implies a very large gulf surrounded by land, except at the communication with the ocean, as the Baltic, Red, and Mediterranean Seas.

INLAND TRADE. That which is wholly managed at home, and the term is in contradistinction to commerce. In China it is applied to canal-trade.

INLET. A term in some cases synonymous with cove and creek (which see), in contradistinction to outlet, when speaking of the supply and discharge of lakes and broad waters, or an opening in the land, forming a passage to any inclosed water.

INNER AND OUTER TURNS. Terms applied to the passing of the reef-earings, besides its over and under turns.

INNER JIB-STAY. A temporary stay lashed half-way in, on the jib-boom; it sets up with lashing-eyes at the fore top-mast head.

INNER POST, or Inner Stern-post. The post on which the transoms are seated. An oak timber brought on and fayed at the fore-edge of the main-post, and generally continued as high as the wing-transom, to seat the other transoms upon, and strengthen the whole. (See Stern-post.) It applies to the main stern-post in steamers, the screw acting between it and the outer, on which the rudder is hung.

INNINGS. Coast lands recovered from the sea by draining.

INNIS. An old Gaelic term for an island, still in use.