DICTIONARY OF

Screw Aperture 295 Scupper Lip
Screw Aperture. Opening, in after deadwood, in which propeller revolves.
Screw Coupling. Joining piece in which a screw thread is fitted for adjusting distance or
tension.
Screw Current. Moving water of the sea that flows along ship's side into the propeller, and
then is driven aft and quarterly by the propeller blades.
Screw Effect. Deviation of a steamship's head from a prolongation of her fore and aft line
when caused by transverse thrust – or paddle-wheel effect - of her propeller. Corrected by
rudder.
Screw Log. Any log that indicates distance or speed by the screw effect of water acting on
inclined planes of the log rotator.
Screw Post. 'Propeller Post.'
Screw Propeller. Immersed system of inclined planes that is revolved by an engine and
forces ship in a fore and aft direction. Usually called 'propeller' or 'screw'.
Screw Race. Turbulent water thrown astern of ship by a revolving propeller.
Screw Rudder. Small screw propeller fitted at angle to fore and aft line of ship. Used for
altering ship's heading, particularly when stopped. Now obsolete.
Screw Stopper. Cable stopper fitted with a bottle screw for tautening.
Screw Well. Vertical trunk into which a propeller could be lifted after being slung in tackles
and tail-end shaft withdrawn. Was used, with more or less success, in old warships having
sail and screw propulsion.
Scroll, Scroll Head. Decorative work at stem head of a ship – as differentiated from a
'figure' head.
Scrowl. 'Scroll.'
Scud. Fractonimbus cloud driven, by the wind, under cumulonimbus.
Scudding. Running before a gale with minimum canvas set.
Scull. Short oar, usually with spoon blade, rowed with one hand. 2. Small boat rowed by one
man.
Sculler. Man who sculls a boat. 2. Boat propelled or impelled by sculling.
Sculling. Propelling or impelling a boat by sculling. 2. Impelling a boat by putting a scull
over the stern, inclining the blade and moving it transversely.
Scupper. Hole in waterways, or bulwarks, for allowing water on deck to flow outboard.
Scuppered. Slang term for frustrated, knocked out, or killed.
Scupper Hole. The hole in a scupper.
Scupper Hose. Short length of pipe to lead scupper water clear of ship's side.
Scupper Leather. Piece of leather used to form a non-return valve in a scupper.
Scupper Lip. Projection on outboard end of a scupper discharge. Ensures water being
thrown clear of ship's side.