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Nautical Definitions

Twenty years or so ago, I ran across a book in the reference section of the California State Library: Shipbuilding Cyclopedia, edited by F.B Webster, J.L Bates, S.M. Phillips, and A.H. Haag, and published in 1920 by the Simmons-Boardman Publishing Company of New York City. What caught my eye at the time were the numbers of fold-out plans of WW1-era merchant ships, and I managed to parlay my status as a State employee into having the staff let me check it out for short periods. Not long afterward, I managed to find a copy from a rare book seller (I don't recall the price, and at this juncture it would probably scare me!). Over the ensuing years I have come to appreciate the value of the 149 pages of nautical definitions at the beginning of the book. They bear preservation and repeating, so I intend to transcribe them here as time allows:


A Dictionary of Ship and Shipbuilding Terms



Aback. The condition of a sailing ship when the pressure of the wind on the sails has a tendency to drive it astern.

Abaft. Towards the stern; aft, relative to.

Abandon. To leave, to forsake. Usually descriptive of the act of leaving a ship when it is no longer safe or seaworthy.

Abeam. At right angles to the vessel's longitudinal axis and in her plane of flotation.

Aboard. On or in a ship.

About. A ship is said to come about when in beating to windward it changes its course allowing the wind to bear on the opposite side of the sails. To change from the starboard to the port tack or the reverse.

Aboveboard. Above deck as distinguished from in the hold or below decks.

Abreast. Over against; opposite. See also Abeam.

Access Hole. A hole cut through a portion of a vessel's structure in order to permit ingress to or egress from a given space or compartment.

Accommodation Ladder. See Ladder, Accommodation.

Accountants. Those who keep records or accounts; bookkeepers.

Accumulator, Hydraulic. A tank designed to store water under pressure.

Accumulator, Pneumatic. A tank designed to store air under pressure.

Acetylene. A gas produced by the action of water upon calcium chloride. This gas combined with oxygen burns with a very hot flame.

Acetylene Gas Compressor. See Compressor, Acetylene Gas.

Acid Open Hearth Steel. See Steel and Iron.

Acidity, Boiler. A term used when the feed water in a boiler is acid.

Admiralty Coefficient. See Coefficient, Admiralty.

Admiralty Metal. Described under Metals.

Admiralty Pump. See Pump, Admiralty.

Adrift. Afloat without effective means of propulsion or control.

Adze. A carpenter's tool having its blade set at right angles with a long curved handle and used for trimming ship timbers. The act of trimming the timbers with this tool is termed "dubbing."

Aft. In the direction of or toward the stern.

After Collision Bulkhead. See Bulkhead, After Peak.

After Deck. See Deck, After.

After Peak. A compartment immediately forward of the stern post. Generally situated entirely below the load waterline.

After Peak Bulkhead. See Bulkhead, After Peak.

After Perpendicular. A line perpendicular to the base line, intersecting the after edge of the stern post at the designed waterline. American naval practice located the after perpendicular at a point of intersection of the designer's waterline and the stern contour.

Aground. The situation of a ship in which its bottom touches or rests on the ground; stranded.

Ahead. Forward; in front of.

Air-break Switch. See Switch, Air-break.

Air Casing, Stack. A ring-shaped plate coaming surrounding the stack and fitted at the upper deck, just below the umbrella. Its purpose is to protect the deck structure from head and to help ventilate the fire room.

Air Compressor. An auxiliary designed to furnish air under pressure for pneumatic tools, cleaning purposes, etc. A form of compressor in common use is the single stage type. This type has two cast iron cylinders, one steam, the other air, each double acting. The steam cylinder is located vertically over the air cylinder, both pistons being on the same rod. Thus, air is compressed and delivered on both the upward and downward stroke of the piston.

Air Courses. A wood ship term applied to air spaces running fore and aft in the sides or bottom of a vessel to provide for a circulation of air to prevent decay in the timbers.

Air Ejector. A steam ejector connected to the condenser dry suction for the purpose of discharging the air and vapor into the atmosphere. A condensate pump handles the condensed steam.

Air Hammer. An air-driven tool arranged to deliver rapid longitudinal impulses against one end of a steel pin. It is contained in a cylindrical shaped casing about three inches in diameter and two feet long with a pistol grip at the opposite end from the pin. Various shaped tools can be fitted on the out end of the pin to perform such operations as heading up rivets or calking and chipping.

Air Holding on Hammer. A tool to hold against the head of a rivet while it is being driven. Its head is fitted on a piston which is cushioned in a cylinder filled with compressed air.

Air Pipes. Pipes leading from tanks to the open air as vents or to provide a supply or escape of air when pumping out or filling the tanks.

Air Port. See Port, Air.

Air Propellers or Beeswing Fans. A fan usually consisting for from two to four blades operated by an electric motor, the blades being so shaped that the air leaves the fan at fight angles to the plane of rotation.

Air Pump. See Pump, Air.

Air Pump, Dry Vacuum. See Pump, Air, Dry Vacuum.

Air Pump, Dual. See Pump, Air, Dual.

Air Resistance. See Resistance, Air.

Air Tight Door. See Door, Air Tight.

Air Trunk or Conduit. The passage forming the main air supply to a fan or exhaust from a fan.

Air Valve. See valve, Air.

Air and Circulating Pump. See Pump, Air and Circulating.

Alarm Valve. See Valve, Alarm.

A-lee. Away from the wind. A sailing ship which constantly requires the helm to be moved to the side of the vessel away from the direction from which the wind is coming in order to keep his course is said to carry a-lee helm.

Alkalinity, Boiler. A term used when the feed water in a boiler is alkaline and has the power of neutralizing acids.

All Hands. Every person on board a ship.

Alligator Shear. See Shear, Alligator.

Alloy Steels. See Steel and Iron.

Aloft. In the tops or upper rigging; on the yards; above the decks.

Alongside. Parallel and in close proximity to. Used frequently relative to a ship lying parallel and close to another ship or a pier.

Alow. Low in or on; below.

Alternating Current. An electric current in which the instantaneous values of current at any point in the circuit vary from zero to a positive maximum value, back to zero; then to a negative maximum value and back to zero. When plotted it consists of half waves of equal area in successive opposite direction from the zero line.

Aluminum Paint. See Paint.

Amidships. In the vicinity of the middle portion of a vessel as distinguished from her ends. The term is used to convey the idea of general locality and not that of definite extent.

Ammeter. An instrument for measuring the electric current flowing in a circuit. The scale of the meter is calibrated to read in amperes.

Ammonia. A volatile alkali, a transparent, pungent gas that can be easily liquefied by pressure. It is used extensively as a refrigerating medium for cold storage systems aboard ship.

Ammonia Joint. On account of the penetrating nature of ammonia, great care should be taken with the joints in a refrigerating system where that alkali is used. The joints should be made of wrought iron or steel, the connections should be soldered after they are screwed in place. Lead gaskets should be placed between flanges and lead or white metal packing use for the valve stems.

Ampere. The practical unit of electric current. It represents that value of current which will cause the electrolytic deposition of silver at the rate of 0.001118 gm. per second.

Analysis of Flue Gas. See Boiler, Analysis of Flue Gas.

Anchor. A heavy iron or cast steel implement attached to a vessel by a rope or chain cable. When the anchor is thrown overboard it lays hold of the ground and holds the vessel in its place. The earlier anchors were made of wood, with one arm and later with two. Stones were attached to give weight to sink and to increase holding power. An iron anchor, having a wood stock, followed the wood anchor. This in turn was replaced by an all-metal anchor. The solid or old-fashioned 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, having the ring bolted to one end and the arms welded to the other, the crown being the heavy end of the shank from which the arms branch out.  The stock is the beam attached to the shank opposite the arms. Various patent anchors exist, most of which are stockless and have their arms pivoted upon the shank.

Anchors, Bowers. The principal anchors carried by a vessel. The are so named because they are carried on the bows. In earlier times they were of different weights, the larger being known as the best bower and the smaller as the small bower. These anchors are now usually the same size.

Anchors, Chains and Hawsers. For method of selections and tables, see under Equipment.

Anchor Deck. See Deck, Anchor.

Anchor Handling Gear. The windlass and gear installed aboard ship, for letting go, taking in and handling the anchor.

Anchor, Kedge. A term applied to a light anchor used for warping or kedging.

Anchor Lights. See Lights, Anchor.

Anchor, Mooring. A term applied to a second or extra anchor used for holding a ship at her mooring.

Anchor, Mushroom. An especial type of anchor having a bowl-shaped crown into the center of which the shank is welded. The upper end of the shank is fitted for the reception of shackle pin as in anchors of the ordinary type. The mushroom anchor has been much used in submarines. It has great holding power in soft bottoms.

Anchor, Sea. A device constructed of spars and canvas in the form of a parachute, to which is bent a hawser or cable. It is put overboard in a heavy sea for the purpose of keeping a vessel head-on to the sea and to enable her to ride out a gale. Also termed a driving anchor or drag.

Anchor, Stream. An anchor used for anchoring in a narrow roadway or channel to prevent the stern swinging with the tide. The weight of this anchor is equal to about one-fourth of the bower anchor.

Anchorage. A suitable place for a ship to lie at anchor. Harbor dues for anchoring in a port.

Angle. An abbreviation for angle iron or angle bar.

Angle Bar. A rolled shape, generally of mild steel, having a cross section shaped like the legs of a right angle. In ship work it is used for frames, bulkhead stiffeners, attachment of one plate or shape to another, etc. The size is denoted by dimensions of cross section and weight per running foot.

Angle Bar Frame. See Frame, Angle Bar.

Angle Bars Frame. See Frame, Angle Bars.

Angle Clip. A term applied to a short piece of angle bar used for attachment.

Angle Iron. See Angle Bar.

Angle Valve. See Valve, Angle.

Angle Furnace. See Furnace, Bar.

Anglesmiths. Workmen who forge steel shapes such as angle or channel bar into the various parts of the ship's hull and fittings such as watertight staples and collars, door frames, etc.

Anneal. To soften metal by heating and slowly cooling. In annealing cast iron the carbon is burned out, near the surface, leaving the outer surface tough and strong while the interior is hard.

Annunciator. An electrical device for giving an audible and visible signal.

Annunciator Wire. See Electrical Wire and Cable.

Anti-Corrosive Paint. See Paint.

Anti-Fouling Paint. See Paint.

Antimony. Described under Metals.

Anvil. An iron or steel block used as a table on which metals are worked or forged. Where an iron block is used the working face is generally made of steel. It is usual to provide a hole about 1-1/4" square for holding working tools such as hardies, fuller blocks, etc. Anvils are used in a shipyard by blacksmiths, anglesmiths and flange turners.

Apeak. In a vertical direction or nearly so. The anchor is "apeak" when the cable has been hauled into a nearly vertical line and the vessel is then "hove apeak." A yard when raised by one end, until nearly vertical is "apeak."

Aperture. The space provided between the propeller and stern post for the propeller.

Appendages. Such items as shaftings, struts, bossings, docking and bilge keels, propellers, rudder and any other feature, extraneous to the hull and generally immersed.

Apprentice. A learner or student of a trade.

Apron. A reinforcing timber bolted to the after side of the stem.

Apron Plate. See Plate, Apron.

Arc, Electric. The luminous vapor of great brilliancy and high temperature between the tips of two electrodes.

Arc, Lamp. See Lamp, Arc.

Arch Piece of Stern Frame. The curved portion of the frame over the screw aperture, joining the propeller and stern posts.

Arching. Occasionally used as descriptive of the same phenomenon as the term "hogging."

Architect, Naval. See Naval Architect.

Ardency. The property of a ship by virtue of which she tends to throw her head up into the wind. Ships having this characteristic must be held on their course by keeping the helm a-weather. The reason for this tendency is found in the resultant lateral resistance of the vessel being before or ahead of her resultant wind pressure.

Area of Sections. The area of any cross section of the immersed part of a vessel, the cross section being taken at right angles to the centerline of the vessel.

Armature. The armature of a generator or motor is that part of the machine containing the winding in which the electromotive force is generated. For direct-current machines, it is usually revolving, while for alternating-current machinery it is usually stationary. The two essential parts of all generators and motors are the field magnet, which produces the necessary magnetic flux, and the armature on which the conductors are arranged.

Asbestos. Principally a silicate of magnesia combined with water. It is used in varying forms where resistance to combustion is necessary. A fireproof composition used for insulation, packing, and lagging. See Insulation.

Ash Chute. A portable iron trough by means of which ashes are discharged overboard clear of the vessel's side.

Ash Ejector. An apparatus for utilizing the discharge water from a pump to convey ashes from the fireroom up and out through the vessel's side above the water-line. It consists of a metal pipe or chute leading overboard above the water-line. At the lower end in the fire-room a hopper is located, and into this the discharge from the pump is led. With the hopper closed and discharge valve opened the stream from the pump will pass with high velocity. The cover may then be removed and ashes dumped into the hopper from which they will be rapidly conveyed overboard by the water.

Ash Expeller. An apparatus for the discharge of ashes from the fire-room below the water level. This type is of value in the case of war vessels when it is desirable to make an opening through the side armor. In this apparatus the ashes are placed in the hopper, from which they pass through a quick-acting valve to an intermediate chamber. An air blast or hydraulic jet expels them from this chamber.

Ash Hoist. Gear for the removal of ashes from the fire-room. It consists of a bucket, usually traveling in guides, a winch for hoisting same to weather deck, and sometimes a trolley track to the ship's side.

Ash Pit, Boiler. See Boiler Ash Pit.

Ashore. Aground (when said of a ship); on shore or land as opposed to aboard or afloat.

Asphalt Solution. See Paint.

Assemble. To collect and place in the proper positions, the various members or fabricated parts entering into construction.

Astern. Signifying position, in the rear of or abaft the stern; as regards motion, the opposite of going ahead; backwards.

Astragal. A small molding placed on the front of one of a pair of doors near the inside edge, to cover the joint where the two doors come together when closed.

Asynchronous Generator. See Generator, Asynchronous.

Athwart, Athwartship. In a transverse direction; from side to side at right angles to the fore and after centerline of a vessel.

Auditors. Individuals who check up accounts and certify as to their accuracy.

Augmentor, Vacuum. An apparatus consisting of a steam ejector and a small condenser with suitable connections and designed to diminish the condenser pressure and enhance the vacuum. A steam jet is installed in an air suction pipe leading from the top of the main air pump suction or from an independent connection to the condenser. The air and vapor entrained are delivered to a small condenser in which the pressure is higher. Circulating water for the augmentor is taken from a by-pass on the circulating pump to the condenser or from a connection to the front head of the main condenser. The ejector steam and the vapor drawn from the main condenser are densified in the augmentor and a water seal is interposed between the augmentor suction and the air pump to prevent the air and vapor from escaping back to the main condenser.

Automatic Reclosing Battery Charging Switch. See Switch, Automatic Reclosing Battery Charging.

Automatic Reclosing Circuit Breaker. See Circuit Breaker, Automatic Reclosing.

Auto-Transformer. A transformer in which a part of the primary winding is used as a secondary winding, or conversely. Sometimes called a Compensator and used for starting alternating current motors.

Auxiliary Circulating Pump. See Pump, Auxiliary Circulating.

Auxiliary Feed Pump. See Pump, Auxiliary Feed.

Auxiliary Foundations. See Foundation, Auxiliary.

Auxiliary Machinery. As its name implies, it includes all machinery except the boilers and engines constituting the propelling machinery proper, and the deck machinery. Under this heading are included such items as Air Pumps, Ash Ejectors, Blowers, Bilge Pumps, Circulating Pumps, Condensers, Distillers, Evaporators, Fans, Feed Heaters, Feed Pumps, Filters, Injectors, Lubricating Oil Pumps, Oil Pumps, Sanitary Pumps, Transfer Pumps, Water Pumps, etc.

Avast. A command to cease pulling on a rope. Stop, cease.

Avast-heaving. A term used on shipboard as a command to stop pulling in the anchor chain.

Awning. A canvas canopy spread over a vessel's decks, bridges, etc. for protection against rain and sun.

Awning Deck. See Deck, Awning.

Awning Deck Sheerstrake. The strake of outside plating adjacent to the awning deck.

Awning Deck Stringer. See Stringer, Awning Deck.

Axis, Neutral. See Neutral Axis.

Azimuth Circle. A graded ring attached to a compass and fitted with vanes, screws and other apparatus. It is used in taking the bearings of the sun, stars and terrestrial objects.



Back-Board. A portable back support nicely designed and fitted on the after side of the stern thwart in a small motor or row boat.

Backbone. A term applied to the keel of a ship and sometimes to the center vertical keelson.

Backing. Making speed or having motion astern.

Back-Firing. See Gas Engine, Back-Firing.

Back Hand Rope. See Rope, Back Hand.

Backstays. Stays which extend from all mast levels except the lower, to the ship's side some distance abaft the mast. They serve as additional supports to prevent the mast from going forward and at the same time contribute to the lateral support, thereby assisting the shrouds.

Baffle Plate, Boiler. See Boiler Baffle Plate.

Balanced Rudder. See Rudder, Balanced.

Bale Measure. A term used where the capacity of a cargo hold is measured to the inside of the frames or cargo battens.

Ballast. Any weight carried solely for the purpose of making the vessel more sea-worthy. Ballast may be either portable or fixed, depending upon the condition of the ship. Permanent ballast in the form of sand, concrete, scrap or pig iron is usually fitted to overcome an inherent defect in stability or trim due to faulty design or changed character of service. Portable ballast, usually in the form of water pumped into or out of bottom, peak or wing ballast tanks, is utilized to overcome a temporary defect in stability or trim due to faulty loading, damage, etc.

Ballast Port. See Port, Ballast.

Ballast Pump. See Pump, Ballast.

Ballast Tank. See Tank, Ballast.

Ballast, Water. Sea water confined to double bottom tanks, peak tanks or other designated compartments for use in obtaining satisfactory draft, trim or stability. In the days of the sailing vessel this object was attained by the use of solid ballast such as sand, gravel, rock, etc.

Ballasted Condition. A condition in which it becomes necessary to fill all or part of the ballast tanks in order to secure proper immersion, stability, and steering qualities. This condition may be the result of the consumption of fuel, stores, and water; or the absence of part or all of the designed amount of cargo.

Ball Joint. See Flexible Joint.

Balsa. A name used in South America to designate rafts made of light wood.

Baluster. Small upright pillar or column supporting the hand rail around a staircase.

Band Saw Filing Machine. See Saw, Band, Setting and Filing Machine.

Band Saw Setting and Filing Machine. See Saw, Band, Setting and Filing Machine.

Banjo Frame. A device for handling the propeller of an auxiliary screw steamer.

Bank. An elevation in the sea's bottom which, if of sufficient height, forms a shoal.

Bar, Boring. See Boring Bar.

Bar Furnace. See Furnace, Bar.

Bar Iron. Rolled bars having various forms of cross section.

Bar Keel. See Keel, Bar.

Bar Stringer. See Stringer, Bar.

Barbettes. Cylindrical structures built up of armor plates extending from the protected deck of a war vessel to the lower side of the turret shelf plate. They form protective enclosures in which are located the turret stools, shell stowage flats and ammunition hoisting gear for the turrets.

Bare Poles. The condition of a sailing ship with no sails hoisted. "Not a rag set."

Barge. A craft of full body and heavy construction designed for the carriage of cargo but having no machinery for self propulsion.

Bark. A vessel having three masts, fore, main and mizzen. The two forward are square rigged and the after or mizzen is fore-and-aft rigged.

Barkentine. A vessel having three masts, for, main and mizzen. The fore mast is square rigged and the main and mizzen fore-and-aft rigged.

Barnacles. A cirriped crustacean which adheres in clusters to the under water portion of vessels, piles, piers, etc.

Bars, Boiler Grate. See Boiler Grate Bars.

Basic Carbonate. See Paint.

Basic Open Hearth Steel. See Steel and Iron.

Basin. A natural or artificial berthing place in which ships may safely float at any stage of the tide.

Basin Dry Dock. See Dry Dock, Graving.

Bath Brick. A calcareous or siliceous earth preparation compressed into bricks and used for cleaning bright-work; so named for having first been made near Bath.

Batten (noun). A thin strip of wood, usually tapered, used in laying down lines. A strip of wood or steel used in securing tarpaulins in place. (Verb) To secure by means of battens, as to "batten down a hatch.

Battening Down. Making the hatches watertight by means of tarpaulins firmly secured to the hatch coamings with battens, wedges, etc.

Battens, Cargo. A term applied to the planks that are fitted to the inside of the frames in a hold to keep the cargo away from the shell plating. These battens are not necessary in concrete ships, as the sides do not sweat.

Batten, Hatch. See Hatch Battens.

Battens, Sheering. Long strips of wood which are clamped to the frames of a ship to locate the edges of the strakes of the shell plating in relation to the sheer of the ship's deck.

Battery, Electric Primary. The apparatus for transforming chemical energy into electric energy is known as a primary cell. Two or more of these cells connected together form a primary battery, although the term "battery" is frequently applied to the single cell as well. There are two general types of primary batteries, wet and dry.

Wet batters consist of two different metals or one metal and a carbon electrode immersed in a chemical solution contained in a glass or porcelain jar.

The dry cell or dry battery is the type most commonly used in marine work. The negative pole is a hollow zinc cylinder and serves as a container. The positive pole is a carbon rod. The rod is surrounded by a deplorazing [sic] agent which is separated from the zinc by some absorbent material saturated with electrolyte. The electrolyte usually consists of sal-ammoniac and zinc chloride, and the top of the cell is sealed.

The dry cell in more convenient, is portable, required less space, and is cheaper than the wet cell, but has the disadvantage of deteriorating whether used or not, and it cannot be recharged.

Battery, Electric Storage. Secondary or storage batteries are devices which transforms chemical into electric energy and the energy of which can be restored by passing an electric current through the battery from some outside source. During the process of restoring or charging the batter the electrical energy is transformed into chemical energy,

Battle Cruiser. A naval vessel of the first class having great speed, carrying guns of the largest size and range and having good protection against gun fire and torpedo attack. She must be so designed as to be capable of keeping the sea in all weathers and have a maximum radius of action. Ships of this class are intended to sink an enemy and under some circumstances to lie in the main line of battle.

Battleship. A naval vessel of the first class carrying maximum armament and protection, both agains fun fire and torpedo attack, and having good speed. She must be so designed as to be capable of keeping the sea in all weather and must have a large radius of action. Ships of this class are intended to lie in the regular line of battle and bear the brunt of the fighting.

Bead. A reinforcing ridge on a pipe or tube.

Beam. The extreme width of a ship. A transverse, horizontal member supporting a deck or flat.

Beam Angle Bar. An angle bar used in the construction of a deck beam or an angle bar comprising a deck beam.

Beam, Awning, Anchor, Main, Lower, Shade, Shelter, etc. The deck beams are given the name of the deck they support.

Beam Bracket. See Bracked, Beam.

Beam, Cant. A term applied to any of the beams supporting the deck plating or planking in the overhanging portion of the stern of a vessel. These beams radiate in fan shaped formation from the transom beam to the cant frames.

Beam Carlines. A term applied to beams either of timber or steel running fore and aft or diagonally between deck beams.

Beam Clamp. A device for attaching to the lower flange of a deck beam for hooking on a purchase, lead block, etc. It is made of metal in two parts, one of which has a sharp bend and hooks over the flange, the other, a straight flat piece, fits against the back of the web of the beam, the two parts being securely bolted together. In the lower end is a worked eye extending through both parts into which a ring is usually fitted.

Beam, Deck--Molding of. Its vertical dimension.

Beam, Deck--Siding of. Its vertical dimension.

Beam, Hold. A term applied to any one of a tier of athwartship beams spanning the hold from frame to frame, and upon which no deck is fitted.

Beam, Intermediate. A term applied to a beam that is fitted in between, and running parallel to, the regularly spaced deck beams.

Beam Knees. A block of wood having a natural angular shape or a block cut to a bracket shape and used for connecting the deck beams to the frames in a wooden vessel. Also applied to the ends of steel deck beams that are split, having one portion turned down and a piece of plate fitted between the split portion, forming a bracket end.

Beam, Main. A term applied to the deck beam fitted at the point of maximum breadth of the vessel.

Beam, Mold. See Mold, Beam.

Beam, Molded. The width over the widest portion of the ship measured to the outside of the frame angle or channel but inside the plating. Extreme: the greatest width outside the plating, armor or any part of the hull proper. Sometimes, but not always, taken over guards or fenders.

Beam, Panting. A term applied to an athwartship beam fitted in the bow or stern of a vessel, to panting stringers or to the under side of decks, for the purpose of preventing in and out motion of the sides of the vessel.

Beam, Transom. A strong deck beam situated in the after end of a vesseldirectly over the stern post, and connected at each end to the transom frame. The cant beams which support the deck plating in the overhang of the stern radiate from it.

Beam and Structural Shape Bender. See Press, Bending.

Beams, Deck. A term applied to any of the main beams upon which the plating or planking of a deck is supported. These beams usually run athwartship from side to side of a vessel and are fastened to the frames. In the way of hatch openings they run from the side to the opening and are bracketed or clipped to the casing or coaming as the case may be. In fore and aft framing, the beams run longitudinally and aare bracketed to the bulkheads and also supported by heavy transverse web or belt beams.

Bear-a-hand. A command to give assistance at whatever is being done. Same as "Lend-a-hand."

Bearding. A term applied to the line of intersection of the plating and stem or stern post.

Bearers. A term applied to foundations and particularly to those having vertical web plates as their principal members. Also the vertical web plates of foundations are called bearers.

Bearing. The ship's bearing is the direction of her course as indicated by the compass. The bearing of an object from the ship is the direction of the object expressed in points of the compass from the ship's course, one point equalling 11 degrees 15 minutes.

Bearing, Rudder. See Rudder Bearing.

Bearings, Roller. See Roller Bearings.

Bearings, Spring. See Spring Bearings.

Beat to Windward. To work up against the wind by means of a series of tacks.

Becalmed. (Applied only to sailing vessels.) That condition in which there is insufficient wind to give steerage way even though all sail is set.

Becket. A small grommet used for various purposes, as for reefing a sail with toggles; the extension of the check straps of a block together with the bold and thimble or eye bolt to which is secured the standing part of the fall.

Bed Plate. A structure, consisting of a series of transverse girders connecting for-and-aft members or girders. It is usually made of cast iron or steel, the girders having box or L-shaped sections. It may be either cast in one piece or built up of several castings bolted together.

Bees. Strips of wood or iron fastened to each side of the bowsprit.

Beetle. A heavy long-handled wood mallet with metal hoops, sometimes called a reaming beetle or hawsing beetle, used by calkers for striking a reaming or horsing iron.

Before. Toward the stem or in front of the vessel.

Belay. To secure a rope or line about a cleat or belaying pin by winding it back and forth in the manner of a figure eight.

Belaying Pin. A small iron or tough wood pin consisting of a head, shouldr and shank. The pin, being securely fitted in a fail, is used for belaying the hauling parts of light running gear, signal halyards, etc.

Bell Crank. A bent lever used to alter the direction of application of a force.

Bell Mouth. A term applied to an expanded, trumpet-shaped fitting, used on the ends of voice tubes, etc.

Bell, Ship's. A bell and clapper of the usual shape used aboard ship as a means of denoting the time at regular intervals by day and by night; viz., 12 o'clock, midday or midnight, 8 bells; 12:20, 1 bell; 1 o'clock, 2 bells; 1:30, 3 bells; 2 o'clock, 4 bells; 2:30, 5 bells; 3 o'clock, 6 bells; 3:30, 7 bells; 4 o'clock, 8 bells; 4:30, 1 bell; 5 o'clock, 2 bells; 5:30, 3 bells; 6 o'clock, 4 bells; 6:30, 5 bells; 7 o'clock, 6 bells; 7:30, 7 bells; 8 o'clock, 8 bells; 8:30, 1 bell; 9 o'clock, 2 bells; 9:30, 3 bells; 10 o'clock, 4 bells; 10:30, 5 bells; 11 o'clock, 6 bells; 11:30, 7 bells. Ship's bells are also used as a signal when anchored in a fog and as an alarm in emergencies.

Below. Underneath the surface of the water. Underneath a deck or decks.

Bend. A term applied to a pipe that is bent through an angle of from 45 degrees to 180 degrees.

Bend, Return. A U-shaped pipe fitting for the purpose of connecting the ends of two parallel pipes, thus providing for a return flow.

Bender, Portable Frame. See Frame Bender, Portable.

Bending Moment. Any beam, girder or structure subject to bending is acted upon by a "bending moment." The bending moment at any point in the structure is the sum of the products of the force acting to producing bending and the perpendicular distances from the lines of action of the forces to the point under consideration.

Bending Press. See Press, Bending.

Bending Rolls. See Rolls, Bending.

Bending Rollers. Men who operate rolls which put a permanent set in sheets and plates when cold, in order that they may conform to the required shape.

Bending Shackle. The heavy shackle which connects the chain cable to the ring or shackle attached to the shank of an anchor.

Bending Slab or Block. A cast iron slab usually about five feet square, perforated with holes 2" square arranged in a manner similar to a checker board. The slab is generally about 2" thick except around the edges where it is about 8" deep. The floor in front of the furnace in the plate and angle shop is made up of a number of these slabs raised to the level of the furnace door. Such work as furnacing plates and bending and beveling is done on these slabs, the holes being used for setting pins around which to bend frames and providing a means for dogging down the work and any forms used.

Bending and Forming Machine. See Press, Forging.

Bending and Straightening Machine. See Press, Bending.

Berth. A term applied to a bed or a place to sleep. Berths, as a rule, are permanently built into the structure of the staterooms or compartments. They are constructed single and also in tiers of two or three, one above the other. When single, drawers for stowing clothing are often built in underneath. Tiers of berths constructed of pipe are commonly installed in the crew space. The term berth is also used to designate a stateroom or cabin, and also to specify a position; for example, he has the berth of captain. Still another use of the term is to designate the place where a ship is docked or tied up.

Bessemer Steel. See Steel and Iron.

Between Decks. The space between any two, not necessarily adjacent, decks. Frequently expressed as "'Tween decks."

Betwixt Wind and Water. At or near the water line at which a ship is floating.

Bevel Board. See Board, Bevel.

Bevel, Closed. A term applied where one flange of a bar is bent into an acute angle with the other flange.

Bevel Gear. A gear designed to transmit power from one shaft to another with which it makes a definite angle. When the shafts are at right angles to each other, the gears are called miters.

Bevel Lines. See Lines, Bevel.

Bevel, Open. A term applied where one flange of a bar is bent out to an obtuse angle with the other flange. In the bow and stern the frames are given an open bevel so that the inner flange will connect to the transverse beams without making it difficult to rivet the outer flange to the shell.

Bevel-Faced Hammer. A hammer used in riveting having its face set at an angle.

Bevel-Faced Holding on Hammer. A large hammer with its face sloped. It is held agains the head of a rivet which it is being driven.

Beveling Machine. A machine used for beveling steel angles and other shapes. A set of steel discs is operated by an electric motor and set to any desired angle by a mechanism attached to a threaded shaft operated at one end by a hand wheel. The bars are heated in a bar furnace and run through the beveling machine while hot.

Bibb. The bent outlef of a cock.

Bight (of a rope). A loop or bend in a rope, though, strictly considered, any part between the two ends may be termed the bight.

Bilge. (Noun) The rounded portion of a vessel's shell which connects the bottom with the sides. (Verb) To open a vessel's lower body to the sea.

Bilge and Ballast System. A system of piping generally located in the hold of a vessel and connected to pumps. This system is used for pumping overboard accululations of water in holds and compartments, and also for filling ballast and peak tanks.

Bilge Discharge Pipe. A pipe on the discharge side of a bilge pump for discharging water pumped from the bilges or bottom of the vessel overboard.

Bilge Ejector. An apparatus designed for the expulsion of the water accumulated in a vessel's bilges.

Bilge Injection. The suction from the bilges to the main circulating pumps which permits discharging bilge water overboard or through the condensers in case of a leak of sea water into the bilge.

Bilge Injection Water. The water pumped from the bilges by the main circulating pumps.

Bilge Inlet. The suction side of a bilge pump or circulating pump which can be used for pumping water from the bilges.

Bilge Keel. See Keel, Bilge.

Bilge Keelson. See Keelson, Bilge.

Bilge Strake. See Strake, Bilge.

Bilge Stringer. See Stringer, Bilge.

Bilge Suction Pipe, See Pipe, Bilge Suction.

Bilge Water. Drainage water which accumulates either in the bottom or the bilge.

Bilge and Fire Pump. See Pump, Fire and Bilge.

Bilgeways. The timbers or part of the launching ways directly under the bilge of a ship.

Bill-board. The inclined anchor bed fitted at the intersection of the forward weather deck and shell. On some ships a tripping device is fitted on the bill-board so that by turning a rod the anchor will slide off into the water.

Bind. To secure the end of a rope agains unlaying by taking turns of twine or small-stuff around it. The term is synonymous with whip.

Binnacle. A stand or case for housing a compass so that it may be conveniently consulted. Binnacles differ in shape and size, according to where used and the size of the compass to be accommocated. A binnacle for a ship's navigating compass consists essentially of a pedestal at whose upper end is a bowl-shaped receptacle having a sliding hood-like cover. This receptacle accommodates teh gimbals supporting the compass. Compensating binnacles are provided with brackets or arms on either side, starboard and port, for supporting and securing the iron cylinders or spheres used to counteract the quadrantal error due to the earth's magnetization of the vessel. This type of binnacle is usualy placed immediately in front of the steering wheel, having its vertical asis in the vertical plane of the fore-and-aft center-line of the vessel.