SECANT. A line drawn from the centre of a circle to the extremity of the tangent.

SECCA. A shoal on Italian shores and charts.

SECOND. The sixtieth part of a minute. A division of a degree of a circle. A term applied both to time and to space. Also, second in a duel; a very important part to play, since many a life may be saved without implicating honour.

SECONDARY PLANET. See Satellites.

SECOND-CAPTAIN. Commanders under captains in the navy, of late.[606]

SECOND-COUNTER. See Counter.

SECOND-FUTTOCKS. The frame-timbers scarphed on the end of the futtock-timbers.

SECOND-HAND. A term in fishing-boats to distinguish the second in charge.

SECOND OFFICER. Second mate in merchantmen.

SECOND-RATE. Vessels of seventy-four guns (on the old scale).

SECTION. A draught or figure representing the internal parts of a ship cut by a plane at any particular place athwart ships or longitudinally.

SECTOR. See Dip-sector.

SECULAR ACCELERATION. See Acceleration of the Moon.

SECULAR INEQUALITY. See Inequality.

SECURE ARMS! Place them under the left arm, to guard the lock from the weather or rain.

SEDITION. Mutinous commotion against the constituted authorities, especially dangerous at sea.

SEDOW. The old English name for the fish called gilt-head; Sparus auratus.

SEDUCE, To. To inveigle a man to desertion.

SEELING. A sudden heeling over, and quick return.

SEER. The tumbler of a gun-lock.

SEE-SAW. Reciprocating motion.

SEGE. An old law-term for the seat or berth in which a ship lies.

SEGMENT. In geometry, any part of a circle which is bounded by an arc and its chord, or so much of the circle as is cut off by that chord.

SEGMENTAL STERN. See Round Stern.

SEGMENT-SHELL. For use with rifled guns; an elongated iron shell having very thin sides, and built up internally with segment-shaped pieces of iron, which, offering the resistance of an arch against pressure from without, are easily separated by the very slight bursting charge within; thereby retaining most of their original direction and velocity after explosion.

SEIN, or Seine. The name of a large fishing-net. Also, a flat seam.

SEIN-FISH. By statute (3 Jac. I. c. 12) includes that sort taken with a sein.

SEIZING. Fastening any two ropes, or different parts of one rope together, with turns of small stuff.

SEIZINGS. The cords with which the act of seizing is performed; they vary in size in proportion to the rope on which they are used.

SEIZLING. A young carp.

SEIZURE. The right of naval officers to seize anywhere afloat, is legally established: a ship, therefore, although incapable of cruising, may still make a seizure in port.

SELCHIE. The northern name for the seal, Phoca vitulina.

SELENOCENTRIC. Having relation to the centre of the moon.

SELENOGRAPHY. The delineation of the moon's surface.[607]

SELLING OUT. An officer in the army wishing to retire from the service, may do so by disposing of his commission.

SELLOCK. See Sillock.

SELVAGE. The woven edge of canvas formed by web and woof. See Boke of Curtasye (14th century):—

SELVAGEE. A strong and pliant hank, or untwisted skein of rope-yarn marled together, and used as a strap to fasten round a shroud or stay, or slings to which to hook a tackle to hoist in any heavy articles.

SEMAPHORE. An expeditious mode of communication by signal; it consists of upright posts and movable arms, now chiefly used for railway signals, electric telegraphs being found better for great distances.

SEMEBOLE. An old term for a pipe, or half a tun of wine.

SEMI-AXIS MAJOR. See Mean Distance.

SEMICIRCLE. A figure comprehended between the diameter of a circle and half the circumference.

SEMI-DIAMETER. The angle subtended by half the diameter of a heavenly body; in the cases of the sun and moon it is much used in navigation.

SEMI-DIURNAL ARC. Half the arc described by a heavenly body between its rising and setting.

SEMI-ISLET. An old term for bridge-islet (which see).

SEND, To. To rise after pitching heavily and suddenly between two waves, or out of the trough of the sea.

SENDING, or 'Scending. The act of being thrown about violently when adrift.

SENIORITY. The difference of rank, or standing in priority, according to dates of commissions; or if on the same day, the order in which they stand on the official printed lists.

SENIOR OFFICER. The commanding officer for the time being.

SENNIT. A flat cordage formed by plaiting five or seven rope-yarns together. Straw, plaited in the same way for hats, is called plat-sennit; it is made by sailors in India from the leaf of the palm, for that well-known straw-hat, adorned with flowing ribbons, which formerly distinguished the man-of-war's man.

SENSIBLE HORIZON. See Horizon.

SENTINEL, or Sentry. A soldier, marine, or seaman placed upon any post, to watch and enforce any specific order with which he may be intrusted.

SENTRY GO! The order to the new sentry to proceed to the relief of the previous one.

SEQUIN. A Turkish and Venetian gold coin of the current value of 6s. 11d.

SERANG. A boatswain of Lascars.

SERASKIER. A Turkish general.[608]

SERGEANT. The senior non-commissioned rank in the army and marines.

SERGEANT-MAJOR. The senior sergeant in a regiment, or first non-commissioned officer; usually a zealous and thorough soldier.

SERON. A commercial package of Spanish America, made of green bullock's-hide with the hair on.

SERPENTARIUS. See Ophiuchus.

SERPENTIN. An ancient 24-pounder gun, the dolphins of which represented serpents; it was 13 feet long, and weighed 4360 lbs.

SERPENTINE POWDER. An old term for a peculiar granulated gunpowder.

SERRATED. Notched like the edge of a saw.

SERVE, To. To supply the gun with powder and shot. Also, to handle it through all the changes of station.

SERVE THE VENT, To. To stop it with the thumb.

SERVICE. The profession; as a general term, expresses every kind of duty which a naval or military man can be called upon to perform. Also, implying any bold exploit.—To see service, is a common expression, which implies actual contest with the enemy.—Service, of served rope, is the spun-yarn wound round a rope by means of a serving-board or mallet.

SERVICEABLE. Both as respects men and stores, capable of or fit for duty.

SERVING-BOARD. A flattened piece of hard wood with a handle, for passing service on the smaller ropes.

SERVING-MALLET. The mallet, grooved on the under side, with which spun-yarn, or other small stuff, is wrapped tightly round a rope.

SERVING OUT SLOPS. Distributing clothing, &c. Also, a cant term to denote punishment at the gangway.

SET. The direction in which a current flows, or of the wind. (See Direction. )—To set, is to observe the bearings of any distant object by the compass. (See Bearing.

) Also applied to the direction of the tide, as "the tide setting to the south," is opposed to a swelling sea setting to the north-west. Also, when applied to sails, implies the loosing and spreading them, so as to force the ship through the water on weighing. When in chase, or other emergency, the term is sometimes used as synonymous with make sail.

SET-BOLTS. Used in drifting out bolts from their position. Also employed for forcing the planks and other works, bringing them close to one another, as Blake's bringing-to bolts, with wood screws, eyes, and rings.

SET FLYING. Sails that do not remain aloft when taken in, but are hauled on deck or stowed in the tops, as skysails, studding-sails, &c.

SET IN. Said when the sea-breeze or weather appears to be steady.

SET ON! The order to set the engine going on board a steamer.

SETT. A kind of shipwright's power, composed of two ring-bolts and a wrain-staff, with cleats and lashings. Also, the particular spot in a river or frith, where stationary nets are fixed.

SETTEE. A single-decked Mediterranean vessel with a long and sharp[609] prow, without top-masts, and carrying lateen sails. They were mostly used as transports to galleys.

SET THE CHASE, To. To mark well the position of the vessel chased by bearing, so that by standing away from her on one tack, she may be cut off on the other.

SETTING. The operation of moving a boat or raft by means of poles. Also, arranging the sights of a gun, or pointing it.

SETTING POLE. A pole, generally pointed with iron, forced into the mud, by which boats and barges are moored in shallow water.

SETTING THE WATCH. The military night guard or watch at the evening gun-fire. Naval watches are not interfered with by time.

SETTING-UP. Raising a ship from her blocks, shores, &c., by wedges driven between the heels of the shore and the dock foundation.

SETTLE. Now termed the stern-sheets [derived from the Anglo-Saxon settl, a seat]. —To settle. To lower; also to sink, as "the deck has settled;" "we settled the land. " (See Laying.

) "Settle the main top-sail halliards," i. e. ease them off a little, so as to lower the yard, as on shaking out a reef.

SETTLING. Sinking in the water.

SET UP. Soldiers, mariners, and small-arm men, well drilled, and instructed to be upright and soldierlike in their carriage, are "well set up."

SET UP RIGGING, To. To take in the slack of the shrouds, stays, and backstays, to bring the same strain as before, and thus secure the masts.

SEVERALTY. The denomination under which disagreements respecting accounts amongst the part-owners of a ship are referred, either to equity courts, or the common law.

SEVERE. Effectual; as, a severe turn in belaying a rope.

SEW, or Sue. Pronounced sue. (See Sewed.)

SEWANT. A north-country name for the plaice.

SEWARD, or Sea-ward. An early name for the custos maris, or he who guards the sea-coast.

SEWED. A ship resting upon the ground, where the water has fallen, so as to afford no hope of floating until lightened, or the return tide floats her, is said to be sewed, by as much as the difference between the surface of the water, and the ship's floating-mark. If not left quite dry, she sews to such a point; if the water leaves her a couple of feet, she is sewed two feet.

SEWIN. A white kind of salmon taken on the coast of Wales. Sometimes this word is used for the dish called sowens.

SEXAGESIMAL DIVISIONS. The circumference of the circle is divided into 360 degrees, each degree into 60 minutes, and each minute into 60 seconds. The Americans afterwards used 60 thirds, but European astronomers prefer decimals.

SEXTANT. A mathematical instrument for taking altitudes of, and measuring the angular distances between, the heavenly bodies. It is constructed on a principle similar to Hadley's quadrant; but the arc contains a sixth part of a circle, and measures angles up to 120°.[610]

SHACKLE [from the Anglo-Saxon sceacul]. A span with two eyes and a bolt, attached to open links in a chain-cable, at every 15 fathoms; they are fitted with a movable bolt, so that the chain can there be separated or coupled, as circumstances require. Also, an iron loop-hooked bolt moving on a pin, used for fastening the lower-deck port-bars.

SHACKLE-BREECHING. Two shackles are turned into the breeching, by which it is instantly disconnected from the port-ringbolts. Also, the lug of the cascable is cut open to admit of the bight of the breeching falling into it, thus obviating the loss of time by unreeving.

SHACKLE-CROW. A bar of iron slightly bent at one end like the common crow, but with a shackle instead of a claw at the bent end. It is used for drawing bolts or deck-nails. (See also Span-shackle.)

SHACKLE-NET. The northern term for flue-net.

SHACKLES. Semicircular clumps of iron sliding upon a round bar, in which the legs of prisoners are occasionally confined to the deck. Manacles when applied to the wrists. (See Bilboes.)

SHAD. The Clupea alosa, a well-known fish, of very disputed culinary merit, owing perhaps to its own dietetic habits.

SHADES. Coloured glasses for quadrants, sextants, and circles. (See Dark Glasses, or Screens.)