DICTIONARY OF

Double Topsail 119 Draft
Double Topsail. Two topsails, without reefs, that take the place of a large topsail that can be
reefed. Sail area is reduced by furling upper topsail.
Double Up. (Moorings.) To duplicate all mooring ropes.
Double Whip. See 'Whip'.
Doubling Angle on Bow. Method of finding distance from a fixed point, or object, by
measuring distance run from a point where its angle on bow has certain value, to another
point where the angle on bow of same object, is double the value of the first. Distance run
between bearings will be equal to distance of observed object at second bearing if course
steered and distance run through water are made good over the ground. Correction must be
made for any leeway, or set and drift of tidal current.
Doubling. Sailing round a point of land. 2. Extra strip of canvas stitched to sail for
strengthening. 3. Turned in edge of sail that takes boltrope. 4. Piece of timber on after side of
wooden bitts. 5. Additional timber fastened to outer skin of vessel when working amongst
floating ice. 6. Generally applied to any lap of plate, planking or canvas.
Doublings. Those parts of a built mast where the upper end of one mast lies abaft the lower
part of a mast extending above it.
Douglas Protractor. Square, transparent, protractor with a graticule of squares, and degrees
marked on the edges.
Douglas Sea and Swell Scale. International scale for recording state of sea by a figure
between 0 and 9; and swell by figures between 00 and 99, upper and lower figures inclusive.
Douse. To lower quickly and suddenly. To extinguish a light by dousing an extinguisher. To
take in a sail. 'Douse the glin': Put out the light.
Dousing Chocks. Pieces of wood laid across apron of wooden ship, and extended to knight
heads.
Dow. 'Dhow.'
Dowel. Small circular piece of wood let into deck plank to cover countersunk head of
fastening bolt.
Dowelling. Joining wood spars by making shaped projections, on one of the parts, fit into
corresponding cut-out portions in the other part.
Down. Said of a tiller when it is put to leeward while sailing.
Downhaul. Rope rove for hauling down purposes. Especially applied to rope by which jib,
staysail, jaw of gaff, or flag are hauled down.
Downton Pump. Double-acting pump in which piston is solid, and valves are so placed as
to be easily accessible for clearing. Used for pumping bilges, or for sea suction.
Dowse. 'Douse.'
Drabler. Strip of canvas laced to bonnet of square sail to increase its area.
Draco. Winding constellation between Lyra and Ursa Minor.
Draft. Old name for a chart. 2. Document authorising one party to draw on the funds of
another. 3. Draught.