DICTIONARY OF

Crew 101 Crosshead
Crew. Personnel, other than Master, who serve on board a vessel. In some cases a
differentiation between officers and ratings is made; but officers are 'crew' in a legal sense.
Crew Gangways. Elevated gangways provided for crew in tankers. Extend from poop to
bridge and from bridge to forecastle.
Crew List. Nominal list of crew, their ages, birthplaces, nationality and rating, together with
other particulars. Delivered to Superintendent of a Mercantile Marine Office after arrival in
U.K. and prior to paying off; also, when required in a foreign port, delivered to Port
Authority.
Crimp. Person who decoys a seaman from his ship and gains money by robbing him and, or,
forcing him on board another vessel in want of men.
Cringle. Rope loop, with or without a thimble, worked into bolt-rope of a sail. See 'Bowline
Bridle'.
Crinolines.* Small lines put on a purchase block and held in hand to steady a lifted weight.
Critical Angle. Least angle of incidence at which a light is reflected.
Critical Pressure. Of steam, is that pressure (3200 Ib. per sq. in.) at which it has no latent
heat and its density is that of water.
Critical Speed. Of turbine, is that rate of revolution that is almost similar to vibration rate of
turbine shaft.
Critical Temperature. Maximum temperature at which a given gas can be liquefied by
pressure. CO2 is 88°F; Ammonia 256°F.
Cro'jack, Cro'jick. Abbreviations of 'Crossjack'.
Cromster. Old name for 'Hoy'.
Cross (in Cable). Exists when cables of a ship moored with two anchors lead on bow
opposite to that of their respective hawse hole. Will occur when ship swings through 180°
after anchoring.
Cross Bar.* Round iron bar bent to Z shape and used for turning shank of anchor when
stowing.
Cross Beam. Heavy piece of timber fitted athwart a pair of wooden riding bitts.
Cross Bearings. Bearings of two or more charted objects that are taken simultaneously and
laid off on chart to fix ship's position.
Cross Channel Packet. Vessel carrying mails between southern England and coast of
France.
Cross Chocks. Filling pieces put at foot of timbers at ends of wood-built ship.
Cross Curves. Diagrammatic curves, based on displacement and righting moment, that
indicate stability at any displacement.
Crossed Observations. Sights taken with Borda's repeating reflecting circle: first
observations being taken with instrument in direct position, second observation with
instrument reversed. This eliminates index error if mean is taken.
Cross Grip. Steel clamp for gripping two crossing wires or hawsers.
Crosshead. Lower, or outer, end of a piston rod. Carries the guide shoes and top end pin of
connecting rod.