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Hair Hygrometer. An instrument often incorporated with a barometer, for discovering the degree of humidity of the air. It comprised a whisker or beard, actually the hair from a seed of wild oats, that formed a spiral when dry, and unwound when damp.

Half Breadth Plan. See Lines Plan.

Half-hour Glass or Clock. This is a sand glass that ran from one bulb to another in half an hour. It was used at sea from the Middle Ages till the mid-19th century. The helmsman would turn the glass as the officer of the watch called the passages of the sun through the meridian. He turned it again at the end of the first half-hour, striking the shipís bell once. After the second half-hour he struck the bell twice and so on.

Half-minute Glass. A sand glass for a half minute, used as log timers, and surviving on sailing ships until the 20th century. Their bulbs were made in one piece, unlike the two-bulbed glasses made to measure longer periods.

Half Hitch. A hitch formed in the end of a rope by passing the end around the standing part and then bringing it up through the bight.

Halyards. Light lines used in hoisting signals, flags, etc. Also applied to the ropes by which gaffs, sail or yards are hoisted.

Hambroline. A cord of three yarns, approximately the same size and yardage as round line. It is used for serving, worming, etc., but is of an opposite twist from round line.

Hammer, Calking. A hammer used in the hand calking of plates, shapes, etc.

Hammer, Plying. A type of hand riveting hammer.

Hammer, Pneumatic. The pneumatic hammer is a combination of a cylinder, a reciprocating piston or plunger, a valve for automatically controlling the movements of the plunger, air, and a throttle valve for regulating the flow of air to the hammer from the supply pipe.

Hammer, Power Forging. A machine which, by means of a crank or eccentric, by steam or by compressed air against a piston in a cylinder, imparts a vertical motion to a hammer or ram die.

Hammer, Set. A hammer used in bringing a shape or frame bar to its final shape on the bending slab.

Hammer, Riveting. See Riveting Hammer.

Hammer Runners. Men who operate power hammers that make large forgings.

Hammock. A rectangular canvas article suspended from hooks attached to the vesselís deck beams or other structure. It is used for berthing seamen aboard ship. Of late years it has been superseded to some extent by fixed berths of various types.

Hammock. A term applied to a swinging canvas bed principally used on war ships. The hammocks are hung from hooks attached to deck beams and are taken down and stowed away during the day time.

Hand Pump. See Pump, Hand.

Hand Spike. A round bar or lever of hard wood which is placed horizontally in the head of a capstan to push against in order to revolve the capstan. A lever for moving heavy weights.

Hand Wheels. Wheels for operating machinery, valves, doors, etc., by hand.

Hank. A ring of rope, wood, or iron that slides on a stay and to which the luff of a staysail is seized.

Harbor Deck. See Deck, Harbor.

Harness. A term, now practically obsolete, for the furniture of a vessel.

Harness Cask. A large tub used to contain the salted provisions intended for immediate consumption.

Harpoon. A long shanked, barb-pointed spear or javelin used to strike whales or other large fish.

Hatch or Hatchway. An opening in a deck through which cargo may be handled, machinery or boilers installed or removed, and access obtained to the decks and holds below.

Hatch, After. A term applied to the deck openings aft of the midship portion of a vessel.

Hatch Bar. A term applied to flat bars used for securing and locking hatch covers.

Hatch Battens. A term applied to the flat bars used to fasten and make tight the edges of the tarpaulins that are placed over hatches. The batten and edge of the tarpaulin are wedged tightly in closely spaced cleats.

Hatch Beams. A term applied to the portable beams fitted to the coamings for the purpose of supporting the hatch covers. The ends of these beams receive hard usage in shipping and unshipping and should be reinforced at these points by doubling strips.

Hatch, Boiler. A hatch fitted over the boiler room through which the smoke stack passes. Iron grating is usually fitted around the stack for ventilation but steel covers that can be closed in heavy weather should also be fitted. This hatch should be made large enough to provide for the installation or removal of the boilers.

Hatch, Booby. An access hatch leading from a weather deck to the quarters. A small companion readily removable in one piece. A wooden hood-like covering, for a hatch, fitted with a sliding top.

Hatch, Cargo. A term applied to the deck openings leading to the cargo holds.

Hatch Carlings. Fore and aft girders running under the coamings at the sides of hatches to which the partial or half deck beams are attached.

Hatch Carrier. A term applied to the supports attached to the hatch coamings which take the ends of fore and afters and cross beams.

Hatch, Ceiling. An opening in the hold ceiling fitted with a cover that can be removed when the cargo is taken out. The object of these hatches is to provide access to the sides and bottom for cleaning and repairs.

Hatch Cleats. A term applied to the clips attached to the outside of the hatch coamings for the purpose of holding the hatch battens and edges of the tarpaulin covers.

Hatch, Coaling. An opening in the deck provided for the purpose of filling the coal bunkers. A trunk or casing is fitted from the upper opening to the top of the coal bunker.

Hatch Coaming. See Coaming, Hatch.

Hatch Covers. Covers for closing up the top of hatchways, usually made of wood planks and in sections that can be handled by the crew. When made of wood one or more tarpaulins are stretched over them to keep out the rain and sea. Watertight covers made of steel plates are also in use, but they are more or less in the way when the cargo is being handled.

Hatch, Crank. A term applied to the hatch over the engines in a paddle wheel steamer.

Hatch End Beam. A term applied to the deck beam at the fore or after end of a hatchway. Where the hatchway does not stop at a deck beam an end beam may be fitted under the coaming or the coaming may be produced down to form an end beam.

Hatch, Engine. A hatch fitted over the engine room. It is usually provided with a skylight having hinged covers that can be operated from below. The hatch should be made large enough to provide for the installation or removal of the engine.

Hatch, Expansion. A term applied to hatches with high coamings fitted on oil tankers for the purpose of allowing space for expansion of the oil.

Hatch, Fore. A term applied to the deck openings forward of the midship portion of a vessel.

Hatch, Grated. A term applied where the top of the hatch is fitted with a wood or steel grating.

Hatch Gratings. See Gratings, Hatch.

Hatch, Main. A term applied to one of the principal cargo hatches.

Hatch Rests. A term applied to the shelf fitted at the top of coamings for the purpose of supporting the edges of the hatch covers.

Hatch Strong Back. A portable beam fitted in a hatchway for the purpose of lifting heavy weights as a beam fitted over the engine in the engine hatch for lifting cylinder covers, etc. The portable hatch beams fitted to the coamings to provide supports for the hatch covers are sometimes called strongbacks.

Hatch, Upper, Main, Lower, etc., Deck. An opening for access or cargo handling in any deck is usually given the name of the deck on which it is situated as Upper Deck Hatch.

Hatch, Watertight. A term applied where the hatch is fitted with a steel watertight cover. The bearing edges of the cover are fitted with strips of rubber which are compressed down on to the coaming by dogs.

Hatch, Wood. A term applied where the side framing of the hatch is made of wood.

Hatchway Gratings. See Gratings.

Hatchway Trunk. A term applied where the space between a lower and the hatch or hatches above it are enclosed by a casing.

Hawse Bag. See Jackass.

Hawse Pipes. Tubes leading the anchor chain from the deck on which the windlass is located down and forward through the vesselís bow plating. Hawse pipes are generally of cast iron or cast steel. They are of heavy scantling and sometimes made in two or more parts to facilitate construction.

Hawser. A large rope, either fiber or wire, used for warping, towing, mooring, etc.

Hawser, Port. See Port, Hawser.

Hawser Reel. A heavy reel for the stowage of hawsers when not in use. In its simplest form it consists of a cylindrical body on which the hawser is wound. At each end a disc shaped guard is fitted to keep the hawser in place. Hawser reels are sometimes mounted on frames and fitted with friction brakes with which to control the paying out of the rope.

Hawser Rope. See Rope, Hawser.

Head of the Bowsprit. The forward end.

Head of Keel. See Forefoot.

Head of a Ship. The fore end formerly fitted up for the accommodation of the crew. A vessel is trimmed by the head when drawing more water forward and less aft than contemplated in her design.

Head-Board. A piece of timber connecting the end of the bobstay with the top of the stem.

Head Sails. The sails forward of the foremast. These are triangular fore and aft sails termed in general jibs and stay sails.

Heads. The upper portions of wood frames. Also used to designate seamenís toilets.

Header. A box or pipe, usually of rectangular cross section and having either a straight or sinuous form, into which the ends of the tubes in water tube boilers are expanded. A pipe or casting into which several smaller pipes are lead. Also the top piece of a door frame or window frame.

Header, Window Frame. The horizontal piece at the top.

Headledge. A term applied to the forward or after end coaming of a hatch. This term is more frequently used in connection with wood coamings.

Heater, Boiler Feed Water. See Boiler Feed Water Heater.

Heater, Fuel Oil. See Fuel Oil Heater.

Heater, Rivet. See Rivet Heater.

Heating System. A system of piping and radiators or pipe coils designed for heating the enclosed spaces and quarters of a vessel during cold weather. Steam is usually used to supply the warmth but hot water installations have been made in special cases.

Heater or Heater Boy. A boy who operates forges to heat rivets for the riveters.

Heating Surface, Boiler. See Boiler Heating Surface.

Heating Tongs. Long handled tongs used by rivet heaters to place rivets in the forge and withdraw them when heated for driving.

Heave. To haul; to cast or hurl; as, to heave the lead, to heave a line, The alternate rising and falling of a vessel in a seaway.

Heave-handsomely. A command to proceed slowly and carefully when pulling in the anchor chain.

Heave-round. A term used on shipboard as a command to start pulling in the anchor chain.

Heaver. A wood bar used as a lever; a sailmakerís tool consisting of a fluted tapered metal pin fitted with a handle at right angles to the pin similarly to an auger.

Heave-To. To bring a sailing ship into such a position that the wind produces no headway. To stop the engines of a ship and lie without headway.

Heaving Line. A small line bent to a hawser, the loose end thrown ashore and caught for the purpose of hauling one end of the hawser to the wharf for making fast.

Heaving the Lead. Taking soundings with a lead and line.

Heel. The inclination of a ship to one side, caused by wind or wave action.

Heel Knee. A bar bent to a right angle or V-shape for the purpose of securely connecting the bottom of the stern post to the keel.

Heel of a Keel. The extreme after end of the keel.

Heel Piece. A bar about three feet long serving as a connecting piece for the ends of frames, whose ends butt together. The flange of the heel bar is reversed from those of the frames it connects.

Heeling. Hauling a vessel over on her side for cleaning and painting; careening; causing a vessel to list to one side by shifting weights on board for the purpose of ascertaining her center of gravity.

Helm. A term applied to the tiller, wheel or steering gear, and also to the rudder. It indicates the control of the maneuvering or steering gear as in the term "Port the helm," and again the position of the rudder in the expression "Lee helm."

Helm Port. A term applied to the hole in the counter of a vessel through which the rudder stock passes.

Hemp Rope. See Rope, Hemp.

Hinge. A fitting used to join doors, covers or parts to partitions or other parts and so constructed that the door or movable part is free to swing or turn on the fitting. Also called butts.

Hitch. A term applied to a variety of methods of bending a line to a post, spar, or ring so that it may be readily detached.

Hogged. Permanently deformed by the action of hogging forces.

Hogging. A distortion of a vesselís form in which the bow and stern drop below their normal position relative to the midship portion of the vessel. Structural weakness, grounding, or improper loading may result in this condition.

Hoist. To raise or elevate by man power or by the employment of mechanical appliances such as cranes, derricks, shear legs, tackles, differential blocks, etc.; any device employed for lifting weights.

Hoist, Electric. Any type of device in which the power for raising weights is furnished by an electric motor.

Hoist, Marine Railway. A winch or windlass located at the head of the tracks for taking in or letting go the rope or chain used for raising or submerging the cradle.

Hoist, Steam. Any type of device in which the power for raising weights is furnished by a steam engine.

Hoisting Crew. Men who have the care of getting on board ship and securing in their proper places any heavy weights requiring the use of shear legs, cranes or other hoisting or moving gear.

Hoisting Engine. A term applied to a winch or any power machine used in hoisting cargo, sails, ashes, etc.

Hold Beam. See Beam, Hold.

Hold Beam Stringer. See Stringer, Hold Beam.

Hold Bunker. A bunker or that part of a bunker below the lower deck. That part of the hold space which may be at times used for stowage of coal for shipís use,

Hold Pillar. See Pillar, Hold.

Hold Stringer. See Stringer, Hold.

Holders-On, or Backers-Up. Workmen who place the rivets in the hole and press against the heads a heavy hammer or dolly-bar while the riveters are hammering up the points.

Holding Ground. An anchorage where an anchor will bite into the bottom so as to prevent it from dragging.

Holds. Spaces or compartments between the lower-most decks and the bottom of the ship, or top of the inner bottom if one is fitted. The spaces below decks allotted for the stowage of cargo.

Holes, Drain. Holes in bulkheads, floors or other obstructions to provide clear flow of liquid to the pump suctions.

Holidays. Portions of a shipís surface which through inadvertence have been missed in the application of paint or other protective coating.

Holland Circle. An altitude-measuring instrument from Holland, produced prior to the Circumferentor.

Hollow Ended. When the extremities of the waterlines in the neighborhood of the designed load line are concave to the surrounding water, and when the sectional area curve at the ends is fine indicating relatively small displacement in these locations.

Hollow Keel. See Keel, Hollow.

Hollows of Resistance. See Resistance, Hollows of.

Holystone. A soft sandstone used in scrubbing wood decks. The origin of the name is probably due to the kneeling posture of the men while using the stone, or else to the fact that they were formerly most frequently used on Sunday; to clean a deck by the application of a holy-stone.

Home. Close up; snugly in place. The port from which a vessel hails.

Hood. A shelter over a companionway, scuttle, etc. It is generally built of canvas spread over an iron frame. It may also be constructed of light metal plating.

Hood Stick. An arrangement designed for holding a drilling machine to be used in light drilling.

Hoods. A term applied to those plates placed at the extreme forward or after end of a ship.

Hook, Breast. A triangular shaped plate fitted between decks or deck stringers in the bow for the purpose of rigidly fastening the stem and fore-hoods of outside plating and the ends of side stringers firmly together. In wood ships a piece of iron bent in a V shape and fitted horizontally in the bow between decks to hold the bow planking in place.

Hook, Deck. A triangular plate fitted at the extreme ends of decks or deck stringers to hold the ends of the decks, the fore-hood plating and stem rigidly together. In wood ships a steamed timber or knee piece fitted at the extreme ends of the decks for the purpose of binding the bow timbers together.

Hook, Fore. See Hook, Deck and Breast.

Hook, Pelican. See Pelican Hook.

Hookers On. Men who place the necessary slings on material to be transported by a crane and assist the crane operator as to the proper disposition of the material.

Hooks. Triangular pieces of plate fitted in the extreme ends of vessels for the purpose of tying the ends of stringers and keeping the outside plating in place.

Horn, Timber. See Timber, Horn.

Horning. Setting the frames of a vessel square to the keel after the proper inclination to the vertical due to the declivity of the keel has been given.

Horsepower. The unit of power is a "horse-power," which is taken as "33,000 ft. lbs. of work performed in one minute" or its equivalent.

Horsepower, Boiler. See Boiler Horsepower.

Horsepower, Effective. The actual power available for propulsion which is equivalent to the indicated or shaft horsepower less all losses due to friction of machinery, line shafting, stern bearings, etc.

Horsepower, Indicated. A term applied to the horsepower actually developed in the cylinder or cylinders of an engine.

Horsepower, Shaft or Brake. A term applied to the power of turbines where it is not possible to use an indicator. It is measured from the shaft by an instrument called a torsion meter, and corresponds to brake horsepower.

Horseshoe Plate. A small light plate fitted on the counter around the rudder stock for the purpose of preventing water from backing up into the ruddertrunk. When fitted in one piece it has the shape of a horseshoe, but it is frequently made in two pieces to completely surround the stock and at the same time permit its removal.

Horsing. A term applied to the operation of driving oakum into the seams between planks.

Horsing Iron. A wide chisel-shaped tool with a wedge-shaped edge fitted with a long handle. It is placed in a seam which has been caulked with oakum and struck with a heavy mallet to drive the oakum down so another thread can be driven or the seam payed with pitch or marine glue.

Hose. A term applied to more or less flexible tubing used to covey water, oil, compressed air, etc.

Hose Couplings. Fittings made in various forms for connecting lengths of hose together.

Hose Nozzles. A tapered pipe having a screw thread cut on the large end for attachment to the end of a hose line.

Hot Well. A receptacle for the water condensed from steam.

Hound Band. A term applied to a band fitted around the upper portion of a mast to provide attachment for the shrouds.

Hound, Mast. See Mast Hound.

Houseline. A tarred hemp, three-stranded, left-handed, small rope, somewhat larger than marline. It is used for both seizing and service.

Housing. A term applied to an enclosure partially or wholly worked around fittings or equipment. Applied to masts it is that portion below the weather deck and to topmasts, that portion overlapping the mast below.

Hulk. The body of an old, wrecked, or dismantled vessel unfit for sea service, but sometimes used for other purposes, as a coal depot, prison, etc.

Hull. The framework of a vessel, together with all decks, deck houses, the inside and outside plating or planking, but exclusive of masts, yards, rigging and all outfit or equipment.

Humps. Portions of curves of resistance or power where, due to disadvantageous wave formation, the residuary resistance is increased relative to that of the adjacent portions of the curves.

Hurricane or Promenade Deck. See Deck, Hurricane.

Hurricane Dial. A curious meteorological instrument, usually made of brass, comprising a compass rose, with several scales and pointers. When these were arranged correctly they were supposed to give a safe route to steer around the path of an impeding hurricane.

Hydrant. An outlet in a pipe line suitable for a hose

Hydraulic Accumulator. See Accumulator, Hydraulic.

Hydraulic Jack. See Jack, Hydraulic.

Hydraulic Riveting. See Riveting, Hydraulic.

Hydrokineter. A device installed near the bottom of a boiler to provide forced circulation of the water when raining steam.

Hydrometer. An instrument for determining the density of the water in a boiler. Also, a mechanical device for measuring a shipís speed termed an "English log", invented by William Foxon in 1772.

Hydrostatic Pressure. See Pressure, Hydrostatic.


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