Shipbuilding Terms and Phrases "B"

Shipbuilding Terms and Phrases 

The following definitions are from United States Shipping Board Emergency Fleet Corporation publication The Building of a Wooden Ship by Charles G. Davis (1918), a long out-of-print book that we have republished and is available on Amazon. They will be very handy when reading the works of such authors as Davis, Howard I. Chapelle, V.R. Grimwood, and others I will reference in this blog. In some cases, I have added further clarification to a definition in the form of editor's notes. These are in italic, contained in parentheses, and attribute the modern author of the clarification.

B 

BACKBONE: the assembled keel stem, stern-post and keelsons; the fore-and-aft rope sewed to the top or back of an awning, to which crowfoot ropes are spliced or thimbles are sewed securely in position. On the heel of the crowfoot into the thimbles the awning halyards or lanyards, which support the awning, are bent. 

BACKING-OUT PIN: a pin used for backing out short or broken treenails or bolts. 

BACK LEGS: a term indicating the struts or timbers bracing or supporting the mast of "A frame" or the mast of a stiff-legged derrick. 

BACK RABBET: the innermost angle or line of the rabbet in the keel or any other part having a rabbet. 

BACKSTAYS: shrouds or standing stays which are attached to or near the topmast heads and lead down to the bulwark channels or ship's top sides. These shrouds are set slightly abaft the mast and are used for the purpose of steadying or guying the topmast. 

BACKSTAY STOOLS: independent small channels attached to bulwarks or vessel's top sides, abaft main channels used for securing the lower end of backstay to the deadeyes or turnbuckles. 

BALLAST: any weight or weights used to trim the vessel or keep her from becoming top-heavy or capsizing; ballast is usually carried in the lower hold under the cargo. It may be fresh or salt water, gravel, shingle, pig-iron, steel rails, etc. A term applied sometimes to cargo which is carried free, or for less than the usual or prevailing rate, the purpose being to increase the stability of the vessel, thus securing a favorable insurance rate and enabling her to go to sea and voyage safely from port to port. 



BAR: a shallow place in the water, generally across the mouth of a river or harbor. 

BARREL: the revolving part of a winch, windlass, capstan or hoisting engine, over which ropes, cables or hawsers wind; the horizontal drum or cylinder permanently attached to a steering wheel around which tiller-ropes are wrapped.  

BARREL BOTTOM: a term descriptive of a vessel with a round bottom like a barrel. 

BARREL-HOOKS: the special shaped hooks attached to a hoisting fall which can seize or take hold and lift a wooden barrel. These hooks grab the barrel in the chimes or end of the staves.  

BARREL-SLING: a sling or method of attaching a rope used for hoisting a headless barrel. 

BATTEN: a thin strip of wood, used by ship's carpenters to reproduce the curves or irregular lines of a vessel's hull.

BATTER: when referring to a vessel, it is a term indicating that the topsides at the upper deck have less breadth than the sides at the water level. The backward or upward slope of the side of the ship from the water level. Sometimes referred to as vessels with "tumbled home sides." 

BAYS: a term indicating amidship. 

BEAD STRAKE: a continuation of the bulwark's rail across frames at bow, stern and amid-ships where ship's frame and sides are carried up higher than rails to support a higher deck; a finish to the topsides. 

BEAM: an athwartship member supporting a portion of a deck; the width of the ship; off to one side: “on the beam"; a vessel laying on her side: "on her beam ends." 

BEAM KNEE: the knee at the end of a deck-beam, by which it is fastened to the hull framing. 

BEARDING-LINE: the line developed by the inner edge of the planking surface against the forward and after deadwood, stem-keel and stern-post. 

BECKET: a strap with an eye-splice at each end; the strap is passed around the mast, one eye passing through the other. The sprit for a sail or hook of a block can be attached in the loose eye, and the weight or strain will set the becket or strap tight on the mast and prevent it slipping; a cleat; a small grommet. 

BEETLE: a heavy wooden mallet used in driving wooden wedges, treenails, pegs and stakes. 



BELAY: to make fast a rope by winding or twisting it around a cleat, bollard, bitt or belaying pin; to attach a rope to a thing by encircling or surrounding it. 

BELAYING POST: see Samson post. 

BELOW: below deck or decks, corresponding to "downstairs." 

Common knots, bends,
hitches & splices

BEND: to make fast or secure the ends of a rope or hawser to the clews of a sail, gaff or yard and mast; to secure one rope to another rope, spar, box, bale, barrel, etc.; "bending a sail or awning"; to open up or spread and secure in position a sail or awning to a yard, boom, gaff, mast, lines, ropes, etc.

BENDS OR WALES: strakes of thick planking on the vessel's topsides. 

BENTINCK SHROUDS: a temporary rope or stay with the upper end lashed to weather side of crosstrees, running athwartship diagonally down across the mast, with lower end made fast to the leeward channels and set up taut. This shroud is for the purpose of bracing the mast and is used when the vessel is in heavy weather and rolling badly or when additional bracing is required for the mast when putting heavy cargo over the side with the vessel's own gear. 

BERTH: the shelf-like bed or bunk used on a vessel by the crew or passengers to sleep in; a location at which a vessel "lays" or cant "lay" whether at anchor or at a wharf or dock. 

BEVEL: any inclination of a surface other than 90 degrees; if the angle of the side or edge of a timber or plank is greater than 90 degrees, it is called “out square” or “standing bevel"; where less than 90 degrees it is called "in square” or “under bevel" 

BEVEL BAND-SAW: a band saw designed to saw bevel frames, sometimes called a ship's saw. 

BEVELLING-BOARD: a board on which the different bevels or angles of the face or edge of a timber frame or plank are marked, used in laying off the bevel on a timber or plank to be shaped. 



BIGHT: to make fast or secure the ends of a rope or hawser to the edge of a sail, gaff, yard or mast; a loop in a rope. 

BILGE: the rounded part of the hull between the side and bottom, either inside or outside of the hull; bilge ceiling; bilge-planking. 

BILGE CHOCK: a timber fitted in between the frames at the bilges. A 2" space is allowed between the chock and the inside face of the planking for air ventilation. 

BILGE DIAGONAL: a line representing the shape of a vessel's hull, drawn on an oblique longitudinal plane from the center line of the vessel to the turn of the bilge on the midship frame. 

BILGE KEEL (KEELSON): a fore-and-aft timber rib, fitted to the outside of the hull at the round of the bilge, used to prevent excessive rolling of the vessel in a heavy sea. 

BILGE-LOG: a term sometimes applied to one of the parallel timbers forming the launching cradle, sliding or traveling ways. 

BILGES: the lowest portion of the vessel inside the hull. 

BILGE-STRAKE: a strake of outside planking at the vessel's bilge. 

BILGE-WATER: water that collects in the bilges of a ship, generally foul water. 

BINNACLE: the stand or case which supports or carries the compass. 

BINNACLE HOOD: the canvas or metal hood which covers and protects the compass. 

BINNACLE LAMP: the small lamp attached to the side of the binnacle hood, used at night to illuminate the compass. 

BINOCULARS (MARINE GLASSES): a light parallel double telescope specially fitted for use at sea. 

BITT: a wood auger used to bore holes in wood. 

BITT OR BOLLARD: the heavy steel or iron castings fitted and fastened down to the deck; large heavy timbers let in through the deck and properly braced below the deck; bitts are used to secure the towing, mooring lines or hawsers to the vessel's hull. 

BLACK STRAKE: the strake of planking above the whale strake. 



BLINKER: a small electric flashlamp used by the navigating deck officer, quartermaster or signal boy to signal or communicate with another vessel or to the shore. 

BLOW, WASH OR SWASH CHOCKS: blocks of wood set in between the frame spaces underneath the floor of the hold. The chocks are set about two or three inches above the inside of the planking; the purpose of these. chocks is to prevent the surging of the water in the bilges when the ship is laboring in a heavy sea. See Swash Chocks. 

BLUFF BOWED: a vessel having a blunt, full or broad forward end. 

BOAT: (in the sense when used in connection with wooden shipbuilding) a small open or decked or partially decked vessel, easily handled and propelled by oars or small-powered engines. It may be used to transport a limited amount of cargo or passengers. There are many kinds of boats; the purpose for which a boat is built is indicated by the name given for that type of craft: canal, fishing, life, motor, quarter, row, surf, water, whale- boat, etc. 

BOAT DECK: the deck on which the lifeboats are carried and stowed. 

BOATSWAIN: a subordinate officer of a vessel, who has general charge of rigging, cargo, etc.; his duty is to handle the crew, under the direction of the mate or other deck officer. 

BODY-PLAN: a plan showing the shape of a vessel at transverse and vertical planes, square with the keel at the different frame stations in her length. The decks, rails and knuckles are also indicated on this plan. 

BODY-POST: the stern-post, also known as propeller post; when the stern-post is made of more than one piece, the post on the forward side against the deadwood is the body-post. 

BOLT: a term referring to a roll of canvas, usually 39 yards in length, regardless of width: an iron rod, sometimes with permanent head at one end, the other end threaded with a nut. Bolts are used for fastening two or more pieces of wood, metal or other things together. 

BOLT-ROPE: the rope that reinforces the edge of an awning or sail; this is generally sewed on. 

BOOM: a long round or oval spar, pivoted at one end, used for hoisting. A spar used to stretch the foot of a fore-and-aft sail. 

BOOM FORESAIL: a triangular fore-and-aft sail, rigged on the foremast, having its foot stretched along a boom. 

BOOM IRON: see Wythe. 

BOOM MAINSAIL: a fore-and-aft triangular sail, rigged on mainmast, having its foot stretched along the boom.

BOOM TACKLE: a double purchase tackle used to guy out a boom. Also known as boom guys, when used on cargo booms.

BOOM TOPPING LIFTS: halyards or ropes leading from the outer end of the boom through a block to the lower masthead, thence down to deck, where they are secured; these ropes are used for topping or lifting up the end of the boom, and when used with a sail, relieve the strain on the throat and peak halyards, particularly when the gaff is used.

BOOT TOPPING: a wooden sheathing laid over planking between light and deep load water-lines; the purpose is to cover any metal bolt heads which would be exposed to the wet and dry action, and thus prevent destructive corrosion. When used as a protection from the Teredo (a wood-boring marine worm-JEH)it is creosoted. The area between load and light water-lines on a ship's side painted another color from that of the bottom or the topsides. 

BOSS: a term applied to the swelling in the stern-post at the stern tube, which allows a sufficient thickness of material outside of stem tube to give strength to the stem-post. 

Elements of Bow Framing illustration from
The Building of a Wooden Ship
By Charles G. Davis

BOW: the forward end of a ship. 

BOWED: a term used to describe the condition of a yard, boom or mast which has been set up so taut as to spring it.

BOW LIGHT: a white, clear light carried forward on the bow or on the forward side of the lower foremast.

BOW LIGHTHOUSE: towers formerly placed on the forecastle deck near the bow of a vessel. These towers carry and protect the port and starboard sidelights; also known as sidelight castles, sidelight towers. Not fitted on modern vessels.

BOWLINE: a curved line or vertical section of a vessel's bow in profile or sheer; also a rope leading from vessel's bow to wharf or another vessel. This rope secures the forward end or bow of the vessel in position.

BOWLINE: a useful rope knot used by sailors and riggers. It is so made that the rope cannot jam or slip and when tied is perfectly safe.

BOWLINE KNOT: a bowline tied with a loop or bight always made at the end of the rope. 

BOWLINE ON A BIGHT: a rope knot; a double bowline.

BOWPORT: a square port cut into the vessel's hull at the bow above the water-line and fitted with a watertight door. This port is used to load or unload long lengths of timber cargo in and out of the hold. 

BOWSPRIT: a spar projecting forward of the stem, inclined slightly upward. Not used on modem steamers.

BOXING THE COMPASS: to name the 32 points of the compass in their regular order. 

BOXING-IN: a term describing the method of notching heels of the cant timbers into the deadwood.

BOXING OF KEEL AND STEM: the scarph uniting the bottom end of the stem to the forward end of the vessel.

BRACE: a term sometimes applied to the rudder gudgeons.

BRAKE: a lever used for operating a deck pump; the lever sometimes used for operating a windlass by hand.

BREAD-BARGE: a box in which to store the ship's bread.

BREADTH: when referring to a vessel, it is a term indicating a measure of distance from side to side. Width as distinguished from length, height or thickness. 

BREAK BULK: to start to unload the cargo. 

BREAKER (BEAKER): a small cask used to carry or store fresh water.

BREAMING: to burn off the marine growth on the bottom of a ship.

BREAST-FAST (BREAST-LINE): a hawser or rope used to secure or moor a vessel alongside a wharf or another vessel.

BREAST-HOOK: the knee at the forward end of the vessel attaching the apron to the shelves, riders or champs.

BREECH: the outer angle of a knee timber; also the becket end of a tackle-block, to which the standing part of a tackle is attached. 

BRIDGE: an observation platform or partial deck from side to side of a vessel, generally located amidships, from which the officer of the deck or pilot maneuvers the vessel. The nautical, navigating instruments and chart house are generally kept or located near the bridge. The bridge is protected with screens and weather curtains and generally has an awning overhead to protect the men in tropical weather. 

BRIDGE DECK: the deck directly back of the bridge, and generally level or nearly level with it.

BRIDLE: a rope secured at both ends in such a way that the middle forms a bight through which the tackle or hoisting rope is attached. The purpose of a bridle is to equalize the strain on each end of the rope, when taking a strain on two objects or on one long object at two different points.

BRINGING UP (BRINGING TO): to bring a vessel up to the wind or in the eye of the wind. 

BROADSIDE: the flat middle portion of a vessel's side, above water-line. 

BROAD STRAKE: the second or third strake of heavy planking from the keel next to the garboard strake.

BUFFALO: the bulwarks extending above the forecastle deck at each side of the stem in the extreme bow of a ship.

BUILDING-SLIP: the fitting-out place where a vessel is completed after launching; this is generally a recess or pocket in the foreshore, or the bank of a river, harbor or bay ; also the building ways on which a vessel's hull is constructed prior to launching.

BUILT-UP (ASSEMBLED): several timbers built in together.

BULKHEAD: a vertical partition corresponding to the wall of a building extending athwart-ships or fore-and-aft.

BULL'S-EYE (A DEADEYE): a wooden fair-lead or pulley, without sheave; a small thin round piece of hardwood having a score around it, in which is fitted the supporting strops or grommet, and provided with one or more smooth holes in the thin part through which to reeve lanyards or ropes.

BULWARK: the ship's side above a deck, applied only when there is no deck directly above; the top sides of a vessel which extend above the deck, like a fence. 

BULWARK NETTING: a netting of ratline attached on bulwark stanchions, generally made in a diamond shape, seized at intersections and used in place of bulwarks.

BUNK: a bed or berth in a ship's cabin, steerage, forecastle, passengers' or crew's quarters; a shelf used as a sleeping place on board a vessel.

BUNKER: a compartment in a vessel used for the storage of coal or other fuel.

BUOYANCY: ability to float, or the difference between the weight of a vessel and the upward force of the water that may be displaced.

BURGEE: a small pennant or house flag.

BURTHEN (BURDEN): the carrying capacity of a vessel; also the weight of cargo, as "a ship of 1,500 tons burden."

BURTON: a type of rope tackle giving great purchase power, sometimes called a single Spanish burton or double Spanish burton. Single burtons are rigged with three single blocks; double burtons are rigged with three double blocks.

BUSH (BUSHING): a special metal sleeve pressed into the hub of a sheave for a tackle- block; this sleeve is of special wear-resisting and lubricating metal and results in the minimum amount of friction on the sheave-pin.

BUTTOCK: a buttock is similar to a bowline, a continuation of it, but applying to that portion of a vessel abaft the midship frame; that part of a ship's under surface forward of the stern.