- Toward the center; within the vessel's shell and below the weather decks.
- INBOARD PROFILE
- A plan representing a longitudinal section through the center of the ship, showing deck heights, transverse bulkheads, assignment of space, machinery, etc., located on the center plane or between the center and the shell of the far side.
- INITIAL STABILITY
- The stability of a vessel in the upright position or at small angles of inclination. It is usually represented by the metacentric height.
- INNER BOTTOM
- A term applied to the inner skin or tank top plating. The plating over the double bottom.
- Occurring between ribs, frames, etc., The term is broadly applied, where two members of a
ship intersect, to the one that is cut.
- ISHERWOOD SYSTEM
- A system of building ships which employs close spaced, relatively light, longitudinal main framing supported on widespread transverse members of comparatively great strength instead of transverse main framing.
- JACK LADDER
- A ladder with wooden steps and side ropes.
- JACK ROD
- A term applied to a pipe or rod to which the edges of awnings or weather cloths are secured.
- Flagpole at the bow of a ship.
- JACOB'S LADDER
- A ladder having either fiber or wire rope or chain sides with wood or metal rungs attached
at regular intervals. One end is usually fitted with sister hooks or shackles for
- A term applied where a plate or bar is offset in the way of a lapped joint.
The object of the joggle is to permit a close fit of the attached member without the use
of liners under alternate strakes of plating.
- JOINT, BUTT
- A term applied where a connection between two pieces of material is made by brining their ends or edges together (no overlap) and by welding alone, or by welding, riveting, or bolting each to a strip of strap that overlaps both pieces.
- JOINT, LAPPED
- A term applied where a connection between two pieces of material is made by overlapping
the end or edge of one over the end or edge of the other and by fastening the same by bolts,
rivets, or welding.
- That portion of a shaft or other revolving member which transmits weight directly to and is in immediate contact with the bearing in which it turns.
- A term applied to temporary structures, such as masts, rudders, etc. used in an emergency.
- A center-line strength member running fore and aft along the bottom of a ship and often referred to as the backbone. It is composed either of long bars or timbers scarfed at their ends or by flat plates connected together by riveting or welding.
- KEEL, BILGE
- A fin fitted on the bottom of a ship at the turn of the bilge to reduce rolling.
It commonly consists of a plate running fore and aft and attached to the shell plating
by angle bars. It materially helps in steadying a ship and does not add much to the
resistance to propulsion when properly located.
- KEEL, BLOCKS
- Heavy timber blocks piled one above the other on which the keel of a vessel is supported when being built, or when she is in a dry dock. They are placed under the keel from bow to stern and a sufficient distance apart to allow working between them.
- KEEL, DOCKING
- In dry docking, the weight of a ship is carried almost entirely on the keel and bilge blocks. The keel and keelson provide the means of distributing the pressure on the center line, and docking keels composed of doubling strips of plate or a heavier plate or built-up girders are sometimes fitted on the bottom at a distance from the center line corresponding to the best position for the bilge block. The docking keels are fitted in the fore and aft direction, generally parallel or nearly so to the keel.
- KEELSON, VERTICAL CENTER
- The lower middle-line girder which, in conjunction with a flat plate keel on the bottom
and a rider plate on top, forms the principal fore-and-aft strength member in the bottom
of a ship. In addition to its importance as a "backbone" or longitudinal strength member,
it serves to distribute and equalize the pressure on the transverse frames and bottom
of the ship when grounding or docking occurs. In steel ships this keelson usually consists
of a vertical plate with two angles running along the top and two along the bottom.
The girder, however, may be made up of various combinations of plates and shapes.
This member should continue as far forward and aft as possible. Usually called the
- Pig iron used either as temporary or permanent ballast or as a weight for inclining a vessel.
- The slit made by the cut of a saw. Also the channel burned out by a cutting torch.
- KING POST
- A strong vertical post used to support a derrick boom.
See Samson Post.
- A block of wood having a natural angular shape or one cut to a bracket shape and used to fasten and strengthen the corners of deck openings and the intersections of timbers, and to connect deck beams to the frames of wood vessels. The term is also applied to the ends of steel deck beams that are split, having one leg turned down and a piece of plate fitted between the split portion, thus forming a bracket or knee.
- A unit of speed, equalling one nautical mile (6,080.20 feet) an hour, as when a ship goes
ten nautical miles per hour, her speed is ten knots.
- An abrupt change in direction of the plating, frames, keel, deck, or other structure of a vessel.
- A framework consisting of two parallel sides, connected by bars or steps which are spaced at intervals suitable for ascending or descending. On shipboard the term ladder is also applied to staircases and to other contrivances used in ascending or descending to or from a higher or lower level.
- LADDER, ACCOMMODATION
- A staircase suspended over the side of a vessel from a gangway to a point near the water to provide easy access to the deck from a small boat alongside.
- LADDER, COMPANION
- A staircase fitted as a means of access from a deck to the quarters.
- LADDER, SEA
- Rungs secured to the side of a vessel to form a ladder from the weather deck to the water.
- A term applied to the insulating material that is fitted on the outside of boilers, piping, etc.
- LANDING, LANDING EDGE
- That portion of the edge or end of a plate over which another plate laps. The covered-up edge.
- The present use of this term is generally limited to a piece of rope or line having one end free and the other attached to any object for the purpose of either near or remote control.
- A term applied to the distance that one piece of material is laid over another; the amount of overlap, as in a lapped joint.
- A term applied to boats built on the clinker system in which the strakes overlap each other. The top strake always laps on the outside of the strake beneath.
- A term applied to a small power or motor boat. See launching.
- A term applied to the operation of transferring a vessel from the building ways into
the water. End launching and side launching methods are employed; the former method is
used when the vessel is built at an angle, usually at right angles, to the waterfront
and the vessel is launched stern first, while in side launching the vessel is built
parallel to the waterfront and launched sidewise. In preparing for an end launching,
usually groundways, made of heavy timbers are laid with an inclination of about
1/2" and 5/8"
to the foot parallel to the center line of the ship one on either side of the keel,
and spaced about one-third of the beam of the vessel apart. These groundways run the
length of the vessel and for some distance out under the water. On top of the groundways
are placed the sliding ways, also heavy timbers, and between these two ways is placed
a coating of launching grease. The sliding ways are prevented from sliding on the
greased groundways by a trigger or similar device and dog or dagger shores.
Cradles are built up to fit the form of the vessel, and between the sliding ways
and the cradle, wedges are driven and the weight of the ship thus transferred from the
building blocks to the sliding ways. After the building blocks and shores are removed,
the trigger is released and gravity causes the vessel to slide down the inclined ways.
In some cases hydraulic jacks are set at the upper end of the groundways to exert pressure
on the sliding ways to assist in overcoming initial friction along the ways.
A similar procedure is followed in the case of side launchings, except that more than
two groundways are usually used, depending on the length of the ship, and the inclination
of the ways is steeper.
- LAYING OFF
- A term applied to the work done by a loftsman in laying off the ship's lines to full size
in the mold loft and making templates therefrom. Also known as laying down.
- LAYING OUT
- Placing the necessary instructions on plates and shapes for shearing, planing, punching,
bending, flanging, beveling, rolling, etc., from templates made in the mold loft or
taken from the ship.
- LEADING EDGE
- That edge of a propeller blade which cuts the water when the screw is revolving in the ahead direction. That edge of a rudder, diving plane, or strut arm which faces toward the bow of the ship.
- LENGTH BETWEEN PERPENDICULARS
- The length of a ship measured from the forward side of the stem to the aft side of the stern post at the height of the designed water line. In naval practice, the total length on the designed water line.
- LENGTH OVER ALL
- The length of a ship measured from the foremost point of the stem to the aftermost part of the stern.
- LIFT A TEMPLATE
- To construct a template to the same size and shape as the part of the ship involved, from either the mold loft lines or from the ship itself, from which laying out of material for fabrication may be performed.
- Transferring marks and measurements from a drawing, model, etc., to a plate or other object, by templates or other means.
- LIGHT, PORT
- An opening in a ship's side, provided with a glazed lid or cover.
- LIGHTENING HOLE
- A hole cut out of any structural member, as in the web, where very little loss of strength
will occur. These holes reduce the weight and in many cases serve as access holes.
This condition is particularly true in floor plates and longitudinals in double bottoms.
- A full-bodied, heavily-built craft, usually not self-propelled, used in bringing merchandise or cargo alongside or in transferring same from a vessel.
- LIMBER CHAINS
- Chains passing through the limber holes of a vessel, by which they may be cleaned of dirt.
- LIMBER HOLE
- A hole or slot in a frame or plate for the purpose of preventing water from collecting. Most frequently found in floor plates just above the frames and near the center line of the ship.
- A general term for a rope of any size used for various purposes: small cords such as long line, lead line, or small stuff as marlin, ratline, houseline, etc.
- A piece of metal used for the purpose of filling up a space between a bar and a plate or between two plates; a filler.
- The plans of a ship that show its form. From the lines drawn full size on the mold loft floor are made templates for the various parts of the hull.
- The deviation of a vessel from the upright position due to bilging, shifting of cargo,
or other cause.
- LOAD LINE
- The line on the "lines plan" of a ship representing the intersection of the ship's form with the plane of the water's surface when the vessel is floating with her designed load on board. Also applied to the actual intersection of the surface of the water with a vessel's side.
- LOCK NUT
- A thin nut which is turned down over the regular nut on a bolt to lock the regular nut against turning off. Also applied to a thin nut placed on a pipe to hold packing at a joint or used on both sides of a bulkhead through which a pipe passes to secure tightness.
- A storage compartment on a ship.
- A man who lays off the ship's lines to full size in the mold loft and makes templates therefrom.
- A term applied to the fore-and-aft girders in the bottom of a ship. These girders are usually made up from plates and shapes and are sometimes intercostal and sometimes continuous.
- A small opening to permit the passage of air for the purpose of ventilation, which may be partially or completely closed by the operation of overlapping shutters.
- Spaces or compartments devoted to the stowage of ammunition. Often specifically applied to compartments for the stowage of powder as a distinction from shell stowage spaces.
- MAIN BODY
- The hull proper, without the deck houses, etc.
- MAIN DECK
- The principal deck of the hull, usually the highest extending from stem to stern and providing strength to the main hull.
- A term applied to the manger-like space immediately forward of the manger plate
which is fitted just abaft the hawse pipes to prevent water entering through the pipes
from running aft over the deck.
- A round or oval hole cut in decks, tanks, boilers, etc. for the purpose of providing access.
- A casting or chest containing several valves. Suction or discharge pipes from or to the various compartment, tanks, and pumps are led to it, making it possible for a pump to draw from or deliver to any one of several compartments.
- MANTLET PLATE
- A thin plate for the protection of personnel, fitted over bolt or rivet heads to act as a screen to prevent the heads flying about when the structure is subjected to impact.
- MARGIN PLANK
- A plank forming the boundary or margin of the deck planking.
- MARGIN PLATE
- The outer boundary of the inner bottom, connecting it to the shell plating at the bilge.
- MARINE RAILWAY
- See drydock, railway.
- MARLINE SPIKE
- A pointed iron or steel tool used to separate the strands in splicing rope, and as a lever in marling or putting on seizings. The wire rope spike has a flat, rounded end and the manila rope spike has a sharp point.
- A double-threaded, left-handed tarred cord, about 1/8" diameter, made of a good grade of American hemp.
- A long pole of steel or wood, usually circular in section, one or more of which are usually located, in an upright position, on the center line of a ship. Originally intended for carrying sails, they are now used more as supports for the rigging, cargo and boat-handling gear and wireless equipment.
- MAST COLLAR
- A piece of wood or a steel shape formed into a ring and fitted around the mast hole in a deck.
- MAST HOUNDS
- The upper portion of the mast at which the outrigger or trestle trees are fitted. Also applied to that portion at which the hound band for attaching the shrouds is fitted on masts without outrigger or trestle trees.
- MAST PARTNERS
- A term applied to wood planking or steel plating worked around a mast hole to give side support to the mast.
- MAST STEP
- A term applied to the foundation on which a mast is erected.
- MAST TABLE
- See Boom Table.
- A space or compartment where members of the crew eat their meals; a dining room. A dining room in which officers eat their meals is called a wardroom messroom.
- MIDSHIP BEAM
- A deck beam of the transverse frame located at the midpoint between the forward and after perpendiculars. Also applicable to the transverse dimension of the hull at the same point.
- MIDSHIP FRAME
- The frame located at the midpoint between the perpendiculars.
- MIDSHIP SECTION
- The vertical transverse section located at the midpoint between the forward and after
perpendiculars. Usually this is the largest section of the ship in area. Also, applied to
a drawing showing the contour of the midship frame upon which is depicted all the
structural members at that point with information as to their size and longitudinal extent.
- Same as Amidships.
- Cut to an angle of 45 degrees or two pieces joined to make a right angle.
- MOCK UP
- To build up of wood or light material to scale or full size a portion of the ship before actual fabrication of the steel work. Used to study arrangement, methods of fabrication, workability, etc.
- A pattern or template. Also a shape of metal or wood over or in which an object may be hammered or pressed to fit.
- MOLDED LINE
- A datum line from which is determined the exact location of the various parts of a ship.
It may be horizontal and straight as the molded base line, or curved as a molded deck
line or a molded frame line. These lines are determined in the design of a vessel and
adhered to throughout the construction. Molded lines are those laid down in the mold loft.
- MOLDED EDGE
- The edge of a ship's frame which comes in contact with the skin, and is represented in the drawings.
- MOLD LOFT
- A space used for laying down the lines of a vessel to actual size and making templates therefrom for laying out the structural work entering into the hull.
- A term applied to the operation of anchoring a vessel in a harbor, securing her to a mooring buoy, or to a wharf or dock by means of chains or ropes.
- MOORING LINES
- The chains or ropes used to tie up a ship.
- MOORING PIPE
- An opening through which mooring lines pass.
- A hole cut in any material to receive the end or tenon of another piece.
- A ship driven by some form of internal combustion engine. Not generally applied to
small boats driven by gasoline engines which are usually called motorboats.
- The vertical bar dividing the lights in a window.
- MUSHROOM VENTILATOR
- A ventilator whose top is shaped like a mushroom and fitted with baffle plates so as to permit the passage of air and prevent the entrance of rain or spray. Located on or above a weather deck to furnish ventilation to compartments below deck.
- NAUTICAL MILE
- See knot.
- NIBBING PLANK
- A margin plank that is notched to take the ends of regular deck planks and insure good calking of the joint.
- A small auxiliary drum on a winch. See Gypsy.
- A piece of pipe having an outside thread at both ends for use in making pipe connections. Various names are applied to different lengths, as close, short, long, etc.
- To heat steel to a temperature slightly above the critical point and then allow it to cool slowly in air.
- NORMAN PIN
- A metal pin fitted in a towing post or bitt for belaying the line.
- The part of a stair tread which projects beyond the face of the riser.
- A substance made from soft vegetable fibre such as hemp and jute impregnated with pine tar. It is principally used for calking the planking on wood decks of steel vessels and for calking all the planking on wood ships where watertightness is desired. It is also for calking around pipes.
- A term used by draftsmen and loftsmen for the coordinates in ship curves. Also applied to joggles in plates and shapes of structural shapes.
- A molding with a concave and convex outline like an S.
- Having the property of resisting the passage of oil.
- OLD MAN
- A heavy bar of iron or steel bent in the form of a Z used to hold a portable drill.
One leg is bolted or clamped to the work to be drilled and the drill head is placed
under the other leg which holds down the drill to its work.
- ON BOARD
- On or in a ship; aboard.
- ON DECK
- On the weather deck, in the open air.
- ORLOP DECK
- The term formerly applied to the lowest deck in a ship; now practically obsolete.
- Away from the center toward the outside; outside the hull.
- OUTBOARD PROFILE
- A plan showing the longitudinal exterior of the starboard side of a vessel,
together with all deck erections, stacks, masts, yards, rigging, rails, etc.
- Outside, over the side of a ship into the water.
- That portion of a vessel's bow or stern which projects beyond a perpendicular at the waterline.
- To repair or put in proper condition for operation; to overtake or close up the distance between one ship and another ship moving in the same direction.
- A general term applied to a yielding material employed to effect a tight joint, also called gasket material.
- PAD EYE
- A fitting having one or more eyes integral with a plate or base to provide ample means
of securing and to distribute the strain over a wide area. The eyes may be either
"worked" or "shackle." Also known as lug pads, hoisting pads, etc.
- A length of rope secured at the bow of a small boat for use in towing or for making it fast. Called also a bow-fast.
- The fluke, or more exactly, the flat inner surface of the fluke of an anchor; a sailmaker's protector for the hand, used when sewing canvas; a flat surface at the end of a strut or stanchion for attachment to plating, beams, or other structural member.
- The pulsation in and out of the bow and stern plating as the ship alternately rises and plunges deep into the water.
- PANTING BEAMS
- The transverse beams that tie the panting frames together.
- PANTING FRAMES
- The frames in the fore peak, usually extra heavy to withstand the panting action of the shell plating.
- The paravane is a special type of water kite which, when towed with wire rope from a fitting on the forefoot of a vessel, operates to ride out from the ship's side and deflect mines which are moored in the path of the vessel, and to cut them adrift so that they will rise to the surface where they may be seen and destroyed.
- Narrow strips of canvas which are tarred and wound around ropes, following the lay and
overlapping in order to shed water. The parcelling is applied after worming, preparatory
- Similar pieces of steel plate, angles, or wood timbers used to strengthen and support
the mast where it passes through a deck, or placed between deck beams under machinery bed
plates for added support.
- A term applied to a pliable canvas hatch cover, and also to pieces of canvas used as a shelter for workmen or as a cover for deck equipment.
- A term applied to a short piece of metal so hinged as to engage in teeth or depressions of a revolving mechanism for the purpose of preventing recoil. Fitted to capstans, windlasses, etc. Also called Pall.
- The operation of filling the seams of a wood deck, after the calking has been inserted, with pitch, marine glue, etc. Also applied to the operation of slackening away on a rope or chain.
- PEAK, FORE AND AFTER
- The space at the extreme bow or stern of a vessel below the decks.
- PEAK TANK
- Compartments at the extreme fore and aft ends of the ship for any use either as
void spaces or as trimming tanks. When used for the latter purpose, water is introduced
to change the trim of the vessel.
- To round off or shape an object, smoothing out burrs and rough edges.
- The lesser head of a hammer, and is termed ball when it is spherical, cross when in the form of a rounded edge ridge at right angles to the axis of the handle, and straight when like a ridge in the plane of the handle.
- PELICAN HOOK
- A type of quick releasing hook used at the lower end of shrouds, on boat grips, and in similar work where fast work may be necessary.
- A navigational instrument, similar to a binnacle and mariner's compass, but without a
magnetic needle, used in taking bearings, especially when the object to be sighted is not
visible from the ship's compass. Also known as a Dumb Compass.
- PERIOD OF ROLL
- The time occupied in performing one double oscillation or roll of a vessel as from
port to starboard and back to port.
- An instrument used for observing objects from a point below the object lens.
It consists of a tube fitted with an object lens at the top, an eye piece at the bottom
and a pair of prisms or mirrors which change the direction of the line of sight.
Mounted in such a manner that it may be rotated to cover all or a part of the horizon
or sky and fitted with a scale graduated to permit of taking bearings, it is used by
submarines to take observations when submerged.
- A vertical member or column giving support to a deck. Also called a stanchion.
- PILOT HOUSE
- A house designed for navigational purposes. It is usually located forward of the midship
section and so constructed as to command an unobstructed view in all directions except
directly aft along the center line of the vessel where the smokestack usually interferes.
- PIN, BELAYING
- A small iron or tough wood pin, made with a head, shoulder, and shank. It is fitted in holes in a rail and is used in belaying or making fast the hauling parts of light running gear, signal halyards, etc.
- A term applied to the pins or bolts which hinge the rudder to the gudgeons on the stern post.
- A term applied to the distance a propeller will advance during one revolution, the distance between the centers of the teeth of a gear wheel, the axial advance of one convolution of the thread on a screw, the spacing of rivets, etc. Also applied to pine tar, asphalt and coal pitch used in paying seams of a deck.
- The alternate rising and falling motion of a vessel's bow in a nearly vertical plane as she meets the crests and troughs of the waves.
- The localized corrosion of iron and steel in spots, usually caused by irregularities in surface finish, and resulting in small indentations or pits.
- PIVOTING POINT
- That point during the progress of a launching at which the moment of buoyancy about the fore poppet equals the moment of the vessel's weight. At this point the stern begins to lift and the vessel pivots about the fore poppet.
- A drawing prepared for use in building a ship.
- Wood covering for decks, etc. The shell of wood boats.
- A partial deck.
- PLATING, SHELL
- The plating forming the outer skin of a vessel. In addition to constituting a watertight envelope to the hull, it contributes largely to the strength of the vessel.
- PLIMSOLL MARK
- A mark painted on the sides of vessel designating the depth to which the vessel may, under the maritime laws, be loaded in different bodies of water during various seasons of the year.
- The property possessed by electrified bodies by which they exert forces in opposite directions. The current in an electrical circuit passes from the positive to the negative pole.
- A scow-shaped boat used in connection with engineering and military operations such as transporting men and equipment, bridge construction, supports for temporary bridges, salvage work, etc. Also applied to cylindrical air and watertight tanks or floats used in salvage operations.
- The structure or raised deck at the after end of a vessel.
- Those pieces of timber which are fixed perpendicularly between the ship's bottom and the bilgeways at the foremost and aftermost parts of the ship, to support it when being launched. They are parts of the cradle.
- The left-hand side of a ship when looking from aft forward. Also an opening.
- PORT, AIR
- See air port.
- PORT FLANGE
- See watershed.
- PORT GANGWAY
- An opening in the side plating, planking, or bulwark for the purpose of providing access
through which people may board or leave the ship or through which cargo may be handled.
- See air port.
- PORT LID
- See deadlight.
- PROOF STRAIN
- The test load applied to anchors, chains, or other parts, fittings, or structure to
demonstrate proper design and construction and satisfactory material.
- PROOF STRENGTH
- The proof strength of a material, part, or structure is the strength which it has been proved by tests to possess.
- A propulsive device consisting of a boss or hub carrying radial blades, from two to four
in number. The rear or driving faces of the blades form portions of an approximately helical
surface, the axis of which is the center line of the propeller shaft.
- PROPELLER ARCH
- The arched section of the stern frame above the propeller.
- PROPELLER GUARD
- A framework fitted somewhat below the deck line on narrow, high-speed vessels with
large screwss so designed as to overhang and thus protect, the tips of the propeller blades.
- PROPELLER THRUST
- The effort delivered by a propeller in pushing a vessel ahead.
- PROPORTIONAL LIMIT
- The stress within which stresses and deformations are directly proportional. Within this limit, on removing stress, there is no permanent set.
- An archaic term for the bow of a ship.
- PUDDENING, PUDDING
- Pads constructed of old rope, canvas, oakum, etc., sometimes leather covered, in any desired shape and size and used to prevent chafing of boats, rigging, etc., on the stem of a boat to lessen the force of a shock.
- A machine for punching holes in plates and shapes.
- PUNCH, PRICK
- A small punch used to transfer the holes from the template to the plate.
Also called a "center punch".
- A flat bottom boat with square ends, used in painting and cleaning a vessel's sides when in port.
- Any mechanical advantage which increases the power applied.
- Flares, rockets, powder, etc., used for giving signals or for illumination, more generally used as distress signals.
- A reflecting hand navigational instrument constructed on the same principle as the sextant
but measuring angles up to 90 degrees only. Also known as an octant. One-fourth
of the circumference of a circle. A fitting in the shape of a sector of a circle secured
to the rudder stock and through which the steering leads turn the rudder. The rim is
provided with two grooves to take the steering chains or ropes and is of sufficient
length of arc so that the leads are tangential to the rim at all rudder angles.
- The upper part of a vessel's sides near the stern; also portions of the vessel's sides about midway between the stem and midlength and between midlength and the stern. The part of a yard just outside the slings.
- An underforeman, a term generally restricted to navy yards.
- Living spaces for passengers or personnel. It includes staterooms, dining salons,
mess rooms, lounging places, passages connected with the foregoing, etc.;
individual stations for personnel for fire or boat drill, etc.
- An artificial wall or bank, usually of stone, made toward the sea or at the side
of a harbor or river for convenience in loading and unloading vessels.
- A groove, depression, or offset in a member into which the end or edge of another member is fitted, generally so that the two surfaces are flush. A rabbet in the stem or keel would take the ends or edges of the planking or shell plating.
- Deformation of the section of a ship, generally applied to a transverse section, so that one set of diagonals in the plane of action is shortened while those at right angles thereto are lengthened.
- RADIO ROOM
- A room, usually sound-proofed, used for sending and receiving radio messages.
- RAFT, LIFE
- A frame work fitted with air chambers to support a number of people in case of accidents. Carried on deck and light enough to be handled without mechanical means.
- The upper edge of the bulwarks. Also applied to the tiers of guard rods running between the top rail and the deck where bulwarks are not fitted.
- A term applied to the fore and aft inclination from the vertical of a mast, smokestack, stempost, etc.
- The action of gangs of men uniting in driving wedges between the cradle and the sliding
ways preparatory to launching or similar activities.
- RANGE, GALLEY
- The stove, situated in the galley, which is used to cook the food. The heat may be generated by coal, fuel oil, or electricity.
- RAT GUARD
- A dished, circular piece of metal made in two parts and fitted closely on hawsers and
lines to prevent rats boarding or leaving a ship while at a dock or wharf.
The concave side is placed toward the shore to prevent boarding, and the guard is
reversed to prevent rats leaving the ship.
- Short lengths of ratline stuff secured to the shrouds parallel to the waterline and
serving as ladder rungs for the crew to ascend or descend.
- Enlarging a hole by the means of revolving in it a cylindrical slightly tapered tool
with cutting edges running along its sides.
- REDUCTION GEAR
- An arrangement of shafts and gears such that the number of revolutions of the output shaft is less than of the input shaft--generally used between a motor or a steam turbine shaft and the propeller shaft.
- The act of passing the end of a rope or chain through an opening, as passing a rope through a block.
- REVERSE FRAME
- An angle bar or other shape riveted to the inner edge of a transverse frame to reinforce it.
- A fore-and-after strip or heavy batten used to support the transverse frames temporarily after erection.
- A term applied to the transverse frames of a boat.
- To float in a buoyant manner while being towed or lying at anchor.
- RIDER PLATE
- A continuous flat plate attached to the top of a center line vertical keel in a horizontal position. Its under side is attached to the floors, and when an inner bottom is fitted, it forms the center strake.
- A term used collectively for all the ropes and chains employed to support the masts, yards, and booms of a vessel, and to operate the movable parts of same.
- RISE OF BOTTOM
- See deadrise.
- The upright board of a stair. A pipe extending vertically and having side branches.
- The fore and aft stringers inside a small boat, secured to the frames, and on which the thwarts rest.
- A metal pin used for connecting two or more pieces of material by inserting it into
holes punched or drilled in the pieces and upsetting one or both ends. The end that
bears a finished shape is called the head and the end upon which some operation
is performed after its insertion is called the point. Small rivets are "driven cold,"
i.e., without heating, and large ones are heated so that points may be formed by hammering.
- The art of fastening two pieces of material together by means of rivets.
- RIVETING, CHAIN
- A term applied to an arrangement of the rivets in adjoining rows where the center of the rivets are opposite each other and on a line perpendicular to the joint.
- RIVETING, STAGGERED or ZIG-ZAG
- A term applied to an arrangement of the rivets in adjoining rows where the rivets in alternate rows are one-half the pitch or spacing ahead of those in the other rows.
- RIVETS, LINE OF
- A term applied to a continuous line of rivets whose centers fall on a line perpendicular to the joint.
- RIVETS, ROW OF
- A term applied to a continuous row of rivets whose centers fall on a line parallel to
the joint. Joints made by one row of rivets are known as single-riveted joints;
by two rows, as double-riveted joints; by three rows, as treble-riveted joints;
by four rows, as quadruple-riveted joints; etc.
- Motion of the ship from side to side, alternately raising and lowering each side of the deck.
- ROLLING CHOCKS
- Same as keel, bilge.
- The product resulting from twisting a fibrous material, such as manila, hemp, flax, cotton,
coir, etc., into yarns or threads which in turn are twisted into strands and several
of these are laid up together. Fiber rope is designated as to size by its circumference.
Wire rope is made of iron, steel, or bronze wires, with and without a fiber core or heart,
twisted like yarns to form strands which are laid up to form the rope. Wire rope
is designated as to size both by its diameter and by its circumference.
- ROPE LAY
- The direction in which a rope is twisted up.
- ROPE, RIDGE
- A rope running through the eyes at the heads of the awning stanchions to which
the edge of an awning is hauled out and stopped. The term "center ridge rope" is applied
to the rope supporting the center of an awning.
- ROPE WORMING
- Filling in the contlines of a rope with marline. The marline should run with the lay of
- Perforated metal plates, fitted over the outside of injection sea cocks to prevent
entrance of foreign substances to the ship's pumps and piping system.
- A U-shaped fitting with a shank or a socket which is attached to the gunwale
of a boat and used as a fulcrum for oars in rowing, sculling, or steering.
- RUBBING STRIP
- A plate riveted to the bottom of the keel to afford protection in docking and grounding.
A strip fastened to the face of a fender or to the shell plating where contact is likely
- A device used in steering or maneuvering a vessel. The most common type consists of a
flat slab of metal or wood, hinged at the forward end to the stern or rudder post.
When made of metal, it may be built up from plates, shapes, and castings, with or
without wood filling, or it may be a casting. The rudder is attached to a vertical shaft
called the rudder stock, by which it is turned from side to side.
- RUDDER, BALANCED
- A rudder having the leading edge of a whole or a part of its area forward of the center line
of the rudder stock, thus advancing the center of pressure of the water on the rudder
and reducing the torque.
- RUDDER BANDS
- The bands that are placed on each side of a rudder to help brace it and tie it into
- RUDDER CHAINS
- The chains whereby a rudder is sometimes fastened to the stern. They are shackled to
the rudder by bolts just above the water line, and hang slack enough to permit free motion
of the rudder. They are used as a precaution against losing a rudder at sea.
These chains are also called "rudder pendants".
- RUDDER FRAME
- A term applied to a vertical main piece and the arms that project from it which form
the frame of the rudder. It may be a casting, a forging, or a weldment.
- RUDDER PINTLES
- See pintles.
- RUDDER POST
- See Stern post.
- RUDDER STOCK
- A vertical shaft having a rudder attached to its lower end and having a yoke, quadrant,
or tiller fitted to its upper portion by which it may be turned.
- RUDDER STOPS
- Fittings attached to the ship structure or to shoulders on the rudder post to limit
the swing of the rudder.
- RUDDER TRUNK
- A watertight casing fitted around a rudder stock between the counter shell plating
and a platform or deck, usually fitted with a stuffing box at the upper end.
- RUDDER, UNDERHUNG
- A rudder that is not hinged to or stepped on the stern post, but is supported entirely
by the rudder stock and the rudder stock bearings.
- The underwater portion of a vessel aft of the midship section or flat of the bottom.
That portion of the after hull that tapers to the stern post.
- RUNNING RIGGING
- Ropes which are hauled upon at times in order to handle and adjust sails, yards, cargo,
etc., as distinguished from standing rigging which is fixed in place.