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secting the sun's disk by keeping the upright wire on the upper limb until the lower limb appears. Read off each bearing. At sunset, when the lower limb touches the horizon, proceed in like manner until the upper limb disappears. The mean of the readings, reckoning from the east or west point, is the observed amplitude. When practicable, the moon may be observed in the same way. In the case of the sun and stars, a table (with latitude and declination for arguments) gives the necessary correction for refraction, to which the requisite dip is added. The same table applied in the contrary way gives the correction for the moon, which is the excess of

the effect of parallax over the combined effects of refraction and dip. The amplitude of a star should be observed at setting, to admit of the body being easily identified.

Ampotis. The running out of the sea.

Amsterdam. An important commercial city, one of the capitals of the Netherlands, at the former confluence of the Amstel with the Y, a lake-like river, now mostly drained, but a small part remains and serves as a port for the city. It has a new artificial harbor on the North Sea, with which it is connected by a ship canal 15 miles long. Pop. 300,000.

Amulet. A charm worn by superstitious people as a preservative against disease or disaster. Amusette. A shoulder-gun fitted with a swivel, carrying a ball weighing from half a pound to two pounds.

Anabus. A bony fish that has the power of living long out of water and moving considerable distances on land.

Anadromous. A term applied to migratory

fishes.

Analemma. An orthographic projection of the sphere on the plane of the meridian. An instrument of brass or wood on which this projection is made. An old form of sun-dial.

Anan. An old word for "What did you say?" Also a corruption of anon.

Anas. A genus of water-birds of the order Natatores, now restricted to the typical ducks.

Anaumachion. Among the ancients the crime of refusing to serve in the fleet, the punishment for which was infamy.

Anchiromachus. A boat of the middle ages for transporting anchors and naval stores.

Anchor. A heavy iron instrument for retaining a ship in her place. It is attached to the ship by a rope or chain, and is thrown overboard from the bows.

The earlier anchors were made of wood with an arm, and later two arms. Stones were attached to give weight to sink and greater holding power. With all the improvements of modern times, the anchors now in use have undergone but little change of form.

After the wooden anchor followed the iron anchor with a wooden stock. At the present day all navy anchors are fitted with iron stocks.

Anchors are solid when the shank and arms are welded together. In most patent anchors the arms are movable and capable of being separated

from the shank.

The solid or common anchor consists of the shank, the ring (shackle, or Jew's-harp), the arms, and the stock.

The shank is the main body of the anchor. The ring is bolted to the upper end and the arms

are welded to the other. The crown is the heavy end of the shank to which the arms are welded. It is the part which first strikes the ground when the anchor is let go perpendicularly.

The stock is the iron beam at right angles to the shank. It has a shoulder near its middle part, and when this shoulder is snug up against the shank it is keyed on the other side. The end opposite to the shoulder is bent for convenience in stowage.

On the ends of the stock are cast-iron balls, the one on the bent end being movable and the other riveted.

The arm consists of the palm (or fluke), the bill (point, or pee), and the blade. The palm is shaped much like a shield, and is welded and riveted to the blade. The bill is the part of the arm which projects beyond the palm. The ring is that part of the anchor to which the cable is bent.

The essential properties of an anchor are strength, holding, quick-holding, canting, facility of sweeping, of stowing, and of transport in boats, exemption from fouling, ing, and quick-tripping. these the most important are strength, holding, and quick-holding.

Of

These qualities depend upon the weight of metal, size and shape of the cross-section of arms and shank, length of arms, shank, and stock, angle at which the arms are set on, size and shape of palm, finish of the bill, curvature of the arm, quality of the material, and the workmanship.

The development of one of these qualities to an extreme degree may involve the sacrifice of another. For instance, the Trotman anchor is notably exempt from fouling, as the upper fluke lies down against the shank, but this peculiarity renders it almost impossible to pick it up by sweeping for it. An anchor that holds well does not trip quickly. The holding power of an anchor depends a great deal on the length of the arm; but a long arm is an element of weakness. So there is much to be considered in the form and dimensions of anchors, and it has required a great many experiments to determine them. The American Anchor, designed by Mr. James Brown, master-smith at the Washington NavyYard, fulfills all required conditions.

Anchors for the navy are forged under the steam-hammer from scrap-iron, and are gotten out in five parts, viz.: the shank, two arms, stock, and shackle (or ring).

The scrap-iron is first hammered into blooms, the most convenient size being 36 inches long, 10 inches wide, and 4 inches thick. The blooms being in readiness, the parts of the anchor are forged and put together in the following order:

The shank. The blooms are piled on the end of a porter bar, heated and welded under a steamhammer until the mass of iron on the end of the bar is of sufficient size to make the shank. The building-up process begins at the crown, and the mass is gradually drawn out towards the ring end, and swaged smooth under the hammer. The holes are punched for the ring and stock, and the

shank is then cut off from the bar.

The two arms are forged separately, also the two palms. The palms are welded on to the arms and riveted, and the bill is drawn out and finished up. The shank is then heated at the crown end, nd, scarfed on one side, and the arm welded on; then scarfed on the other side and the second arm welded on. The arms are welded on straight, and afterwards heated and bent to the proper angle.

The stock is forged from blooms in the same manner as the shank. The ring is forged straight, and afterwards heated and bent to the proper shape and a bolt fitted to the eyes.

The process of annealing anchors has now generally gone out of use.

The following are the proportions of a 6000pound anchor:

Shank.-Length, 13 feet 8 inches; cross-section at the largest part where the arms are welded on, 10 by 8 inches; cross-section at the stock, 8 by 7 inches, the greatest dimension being in the plane of the arms.

Stock. The length is equal to the length of the shank over all, and in diameter it is about two-thirds the smallest width of the shank measured in the plane of the arms.

The length of the arm is nearly one-third the length of the shank, and in bending them an equilateral triangle is formed with the length of the arm for one side, the same distance laid off on the shank from the crotch for the second side, and the distance from the end of this line to the bill completes the triangle.

In forging anchors a great deal is done by eye for shape and proportions. The crown and throat are rounded off, and the shank has eight faces, with a straight taper from the crotch to the stock. The weight of an anchor is inclusive of the ring and exclusive of the stock, which is about one-fourth the weight of the anchor.C. T. Hutchins, Lieutenant U.S.N.

PATENT ANCHORS. Many designs have been submitted, the most prominent of which are mentioned below. The oxidation of the movable parts of portable anchors is the great source of failure, as they require constant care and attention to keep them in working order.

Isaac's Anchor has a bar of iron from each end of the stock to the middle of the shank, and the palms are connected by a flat elliptical bar of iron. It has great strength, and is notably exempt from fouling, but is deficient in other respects.

Latham's Anchor has an arm provided with three flukes, and the shank is made of two pieces, which separate at the crown end to allow the midship fluke to pass. When the three flukes enter the ground, the flange on the crown-piece takes on the shank and the arms are held rigid. No stock is required.

Marshall's Anchor. The arms are straight and move independently on a pivot, which passes through the crown. The arms are fitted with projections, which assist the flukes to enter the ground.

Martin's Anchor is supplied to the turret-ships of the British navy. The anchor is very compact, and for that reason is especially recommended to rams and turret-ships, as it does not impede the fire nor project from the bows.

Morgan's Anchor has a curved bar of iron, which passes through a slot in the shank and connects the two arms to each other. The arms are separately pivoted to the shank. When one fluke enters the ground the other is drawn down against the shank, the connecting bar serving to strengthen the arms.

Porter's Anchor is the same in principle as Trotman's, which see.

Rodger's Anchor has a shank with a wooden core, the object being to give greater strength with a given weight of metal. He also designed the pick-ax anchor, an anchor without palms.

Trotman's Anchor. The oscillatory system is the principal feature of this anchor. The arms are in one piece and work in a slot in the shank. When one fluke enters the ground the other is drawn down against the shank. The backs of the arms are fitted with horns to assist the flukes to enter the ground. It is one of the best of the patent anchors.

The BOWER-ANCHORS are so named from their being carried on the bows. In early days they were of different sizes; the larger one, called the best bower, was carried on the starboard bow, the other was known as the small bower. These designations are yet retained, though the anchors are now of equal size.

The WAIST- or SHEET-ANCHORS are equal in weight to the bower-anchors, and are carried on the side, abaft the fore-rigging. They are secured with the stock perpendicular, and the shank resting on two shores.

The SPARE-ANCHOR, when no sheets are carried, is of the same size as a bower-anchor, and is stowed inboard.

The STREAM-ANCHOR is one-fourth the weight of the bower-anchor, and is carried inboard. KEDGES are small anchors, from one-sixth to one-fourteenth the weight of the bower. They are stowed in the chains.

BOAT-ANCHORs are small anchors supplied for the use of the boats. They are stowed in the hold of the ship until needed for service.

With reference to their position anchors are termed flood, ebb, weather, lee, sea, or shore anchors.

TO SHOE AN ANCHOR. To fit triangular pieces of wood to the palms to give greater holding power.

TO COCKBILL THE ANCHOR. To ease off the shank-painter, and hang the anchor by the ringstopper.

TO LET GO THE ANCHOR. To release it from the cat-head that it may fall to the bottom and hold the ship.

TO DRAG THE ANCHOR. To trail it over the bottom by force of the wind or current.

TO BACK THE ANCHOR. To increase the holding power of an anchor by planting a smaller one ahead of it, and connecting the two with a chain. The holding power of an anchor may be increased by attaching a weight to the bight of the chain, thus bringing the strain lower down, and causing the fluke to bite harder.

TO TRIP THE ANCHOR. To heave it clear of the bottom.

TO SIGHT THE ANCHOR. the surface of the water.

TO WEIGH AN ANCHOR. the bows.

To heave it up to To heave it up to

TO CAT THE ANCHOR. To hoist it up to the cat-head and pass the ring-stopper.

TO FISH THE ANCHOR. To hoist the flukes up to the bill-board and pass the shank-painter. TO STOW AN ANCHOR. To secure it in its proper place.

TO TRANSPORT AN ANCHOR. To shift it from one position to another in the ship.

TO SECURE THE ANCHOR FOR SEA. To ring it up close to the cat-head, and get the inner fluke inboard, and pass extra lashings.

TO GET THE ANCHOR OFF THE BOWS. To take off the extra lashings, and heave the inner fluke up and outboard, so it will slip off the billboard when the shank-painter is let go.

TO SWEEP, DRAG, OR CREEP FOR AN ANCHOR. To endeavor to pick up an anchor or the chain by trailing for it with a grapnel or the bight of

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Anchor, Jury. A temporary anchor constructed to supply the place of one which has been lost. Ships are sometimes obliged to resort to their guns, boilers, and other heavy articles. Anchor, Mushroom. Has head sh shaped like a bowl, and no stock is required. It is used for moorings.

a

Anchor, Screw. Large screws with broad flanges, used for moorings and to shoe piles.

Anchor, Sea. A species of raft or drag formed of spars and canvas to keep a ship's head to the wind and to decrease her drift. It is attached to the ship by a hawser, and is generally fitted with a buoy and an anchor.

Anchorage. A duty levied upon vessels upon coming to a port for the use of its advantages. The set of anchors belonging to a ship. A place suitable for anchoring. It is marked on charts by an anchor, and is described according to its attributes as good, snug, open, or exposed.

Anchor-ball. A pyrotechnical combustible attached to a grapnel.

Anchor-bar. A large handspike to pry the anchor off the bill-board.

Anchor-chock. Pieces let into an anchorstock. Pieces of wood or iron upon which an anchor rests when it is stowed.

Anchor-hold. The fastness of the flukes in the ground.

Anchor-hoops. Heavy iron hoops binding a wooden stock to the shank and over the nuts of the anchor.

Anchor-ice. The ice which forms on and incrustates the beds of lakes and rivers.

Anchoring. (p. pr. of v. t. TO ANCHOR.) (Lat. ancora, anchor.) The manœuvre by which a wessel is brought to anchor, ie. brought to a state of temporary rest and security by means of an anchor let go from the vessel.

The anchor, attaching self to the bottom, is enabled by means of the intervening cable to hold the vessel in Cace. A vessel may be brought to anchor under a great variety of conditions of wind, tide, and sea.

anchors (see ANCHOR) and their cables should be in readiness for use, always having the second anchor ready to let go in case the first, from any cause, should fail. Second, that the vessel should be head to tide, or nearly so, when the anchor is let go. Third, on approaching the anchorage, under favorable circumstances, the speed of the vessel should be gradually reduced, then stopped, and finally a stern-board be given her, either by the action of the wind or tide, or by the use of sails or engine. The moment of starting astern is that for letting go the anchor. Fourth, that the vessel should have sufficient stern-board to lay her cable out clear and straight from the anchor. Fifth, that the stern-board should not be so great as to endanger running out too much cable, or of parting in attempting to check it. Sixth, that when the cable is finally secured there should be a good scope out. Seventh, that when anchored the vessel should be in a good berth.

It is generally conceded that a vessel should never ride to a shorter scope of cable than six times the depth of water. That is to say, if anchored in ten fathoms of water she should not have out less than sixty fathoms of cable for ordinary security. In general, there are three different classes of vessels that may be treated of under this head: the square-rigged sailing-vessel, the fore-and-after, and the steamer. To bring one of the former into a crowded harbor, to pick out a good berth and come to anchor in a proper manner, calls forth all the skill and judgment of a practical seaman, and an amount of knowledge which can be obtained only by long and varied experience.

With a schooner we have, ordinarily, only to haul down the head-sails, luff up into the wind, and when the headway is lost and she begins to go astern, to drop the anchor, and then to pay out the necessary scope as she takes it. Or beating in with a strong windward tide (see TIDES), we should reverse the operation; lower the fore and mainsails, wear around under the jib, and, when head to tide, let go the anchor.

With a steamer the operation is still more simple. Steering directly for her berth, the engines are first "slowed," then stopped, and finally backed, if necessary; when the headway ceases the anchor is let go and the cable paid out as she takes it. If she had been steaming hing in against the tide she will, on stopping the engines, soon go astern and take her cable. If she has the tide with her, as soon as the anchor touches the bottom she will begin to swing to the tide. When head-to, pay out to the necessary scope.

ANCHORING BY THE STERN is to have the cable brought in through a stern-chock, so that when the anchor is let go from the bow the vessel will ride by the stern.

ANCHORING WITH A SPRING: to attach a hawser to the ring of the anchor before letting go, so that when the anchor is down and an equal strain brought upon the cable and the hawser, the vessel will ride to a bridle, presenting her broadside to the wind or tide as either may prevail. The vessel's head may be then made to change direction by shortening in, or veering on the cable or hawser, as desired.

The peculiar nature of the anchorage itself, and the number of vessels occupying it, must also be considered. For the minor details of all that precede, accompany, and follow this manœuvre, The two last manœuvres are practiced in war: the reader is referred to works on Seamanship. the former when it is undesirable to swing The principal points to be observed are, First, around, as when anchoring in the ordinary way; that on approaching the anchorage both bower | the latter when it is desired to change the ship's

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Angle. A corner. The difference in direction of two lines in the same plane, proceeding from the same point.

A SPHERICAL ANGLE is formed by the intersection of two great circles. It is the inclination of the planes of these circles to each other. A SOLID ANGLE is formed by the meeting of three planes at one point. See ELEVATION, FIRE, SIGHT, MAST-HEAD, LEEWAY. Angon. A half-pike or javelin. Angosiade. An astronomical falsehood; a term originating from the pretended observations of D'Angos at Malta.

Angra. (Sp.) Bay or inlet.
Anguilliform. Having the appearance of

[graphic]

eels.

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Anna. In the East Indies, the 16th part of a rupee, about three cents in United States currency.

Annapolis. A city and port of entry in Maryland, on the S.W. bank of the Severn River, 3 miles from its entrance into the Chesapeake Bay, 30 S. by E. from Baltimore. Lat. 38° 58′ 50′′ N.; lon. 76° 30′ W. The United States Naval Academy is here located. Pop. about 6000.

Annealing. There are many substances which, when rapidly cooled after having been heated, become exceedingly brittle; this result may be prevented by very slow cooling, which process is termed annealing. By this process the substance is rendered softer and less brittle, but its elasticity is impaired.

Annet. A kind of gull.

Annex. A term used on the Mississippi and other Western rivers to indicate the pilot-house of steamboats, called also "Texas." The term is said to have originated about the time of the annexation of Texas to the United States.

Annihilator, Fire. See FIRE-EXTINGUISHER. Anniversary Winds. Those which blow constantly at a certain season of the year; as, monsoon and etesian winds.

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the sun, and a ring of light surrounds the moon while central.

ANNULAR SCUPPER. A scupper in which the hole may be enlarged or diminished by a movable concentric ring.

Annulling Signal. A signal which denotes that the previous signal is void.

Annulus Astronomicus. A ring of brass used formerly in navigation.

Anode. The positive pole of an electric battery; or, more strictly, the path by which the current passes out and enters the electrolyte on its way to the other pole; opposed to cathode.

Anomalistic Revolution or Period. The period during which a planet makes a complete revolution from any point in its orbit back again. ANOMALISTIC YEAR, OF PERIODICAL YEAR. The time in which the earth makes its anomalistic revolution, which is longer than the tropical year on account of the precession of the equi

noxes.

Anomaly. Deviation from established rules. Anomoural. Irregular in the character of the tail or abdomen; as, the anomoural crustaceans, a group between the crabs and the shrimps.

Anon. Quickly; immediately. At another time.

Anonymous Partnerships. Those not carried on under a special name, and the particulars of which are known only to the parties themselves. Ansæ. The handles of old ordnance. The projections of Saturn's rings in certain situations. Anser. A Linnæan order of natatorial birds swimming by means of web-feet, as the duck, or of lobe-feet, as the grebe.

Anson, George, Lord. An English admiral; born in Staffordshire, England, in 1697; entered the navy at an early age, and in 1724 was made post-captain. He was soon ordered to the Carolina station, where he purchased land and built a town called after his own name. He was subsequently appointed to the command of the South Sea Expedition which sailed from England in 1740. After his return, in 1744, he was successively created rear-admiral of the blue, commissioner of the admiralty, and vice-admiral.

In

1747 he commanded the Channel Fleet, and captured six French ships of war. As a reward for this brilliant exploit he was created a peer, with the title of Lord Anson, Baron of Soberton. He was First Commissioner of the Admiralty from 1751 to 1756. In 1757 Anson was made admiral, and in the same year was placed at the head of the admiralty. Died in 1762. No book in the English language possesses a greater charm for youth and the lover of adventure than "Anson's Voyage."

Answer. To reply. To suit; as, this boat will

not answer.

ANSWER THE HELM. A ship is said to answer the helm when she obeys it readily.

Answering Pennant. A pennant which is hoisted to indicate that a signal has been read and understood.

Antarctic. Relating to the South Pole or to the region near it.

ANTARCTIC CIRCLE. A parallel 23° 28′ from the South Pole.

ANTARCTIC POLE. The South Pole.

ANTARCTIC OCEAN. The portion of the ocean included within the Antarctic Circle.

Antares. A star of the first magnitude, popularly known as the Scorpion's heart (a Scorpionis). Antecians. Those inhabitants of the earth who live on the same meridian, but in opposite hemispheres.

Antelucan. Before daybreak.
Ante-meridian. Before noon.

Anthelion. A luminous appearance on a cloud, over against or opposite to the sun. It consists of a circular ring or rings around the shadow of the spectator's own head as projected on a cloud or on some opposite fog-bank.

Anthracite. See COAL.

Anticthones. Inhabitants of countries diametrically opposite to each other. Anti-friction Composition. See FRICTION. Anti-friction Metals. See FRICTION.

Anti-gallicians. Extra backstays sometimes used by merchant vessels running before the trades.

Anti-guggler. A straw or tube introduced into a bottle or cask to suck out the contents. Anti-parallels. Lines which make equal angles with two other lines but contrary ways. Antipathes. A kind of coral having a black, horny stem.

Antipodes. The inhabitants of the earth diametrically opposite to each other. The term is now applied to the countries which are at the opposite ends of any diameter of the earth.

Antiscii. The people who dwell in opposite hemispheres, and whose shadows at noon fall in contrary directions.

Antiscorbutic. Opposed to, or counteracting scurvy. See SCURVY.

Antiseptic. Opposed to, or counteracting putrefaction, or tendency to putrefaction, in the system.

Antlia. A constellation known as the AirPump.

Antwerp. A city of Belgium, on the right bank of the Scheldt. Lat. 51° 13′2′ N.; lon. 4° 24' 2" E. It is strongly fortified, the walls and other defenses completely incompassing the city on the land-side, having more than 12 miles of solid ramparts. Of the stocks, dock-yard, and basins, constructed by Napoleon at an expense of $10,000,000, the last only remain. The harbor is one of the finest in the world; it admits vessels of any size, and can easily hold 1000. Pop. 150,000.

Anvil. The massive block of iron on which shipsmiths hammer forge-work. A streamer at the end of a lance.

Any Port in a Storm. A phrase signifying contentment with one's lot. The best practicable way out of a difficulty.

Ape, or Sea-Ape. The long-tailed shark. An active American seal.

Apeak. Near the perpendicular. An anchor is apeak when the chain is up-and-down. The oars are apeak when the blades are thrown forward and the crew is waiting for the order to "give way" in racing. With an awning spread in a boat it is impossible to "up oars." When they are raised as high as the awning permits they are said to be apeak.

Apertæ. Ancient deep-waisted ships with high-decked forecastle and poop.

Aperture. The clear diameter of the object

opti

glass of optical instruments.

Apex. The summit or vertex.

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