DICTIONARY OF

Radio 271 Raker
Radio. General name for methods of signalling or communicating through space by electromagnetic
waves.
Radio Aids. Term that includes all radio signals and emissions that can be used in
navigational practice.
Radio Beacon. A radio station which sends out special signals for reception by a ship's radio
direction finder, the bearing of the radio beacon being thus obtained.
Radio Compass. Directional radio receiver calibrated to indicate the direction in which a
radio wave approaches.
Radio Direction Finder. Instrument for detecting a radio signal and for indicating the
relative bearing on which it is received.
Radiolaria. Minute creatures having a spherical, or conical, body from which small
filaments project.
Radiolarian Ooze. Deep-sea deposit containing minute skeletons of radiolaria. Forms sea
bed of large areas of Pacific and Indian Oceans at depths of 2000 to 5000 fathoms.
Radiosonde. Small compact radio transmitter attached to a free balloon for the purpose of
obtaining upper air observations.
Radio Time Signal. Time signal broadcast by radio.
Radius Vector. Line from a pole, or focus, that fixes position by measurement of angle
between vector and a primitive. In astronomy, is a straight line connecting a planetary body
with Sun.
Radome. A bun-shaped cover placed over a radar scanner to prevent risk of fouling and to
protect it from the weather.
Raft. Floating structure made for life-saving purposes in shipwreck. 2. Timber or logs
fastened together for transport by water.
Rafting. Overlapping of edges of two ice-floes, so that one floe is partly supported by the
other.
Raft Port. Square opening, in end of ship, for loading long timber.
Rag Bolt. Bolt having jagged cuts across shank, to prevent bolt working out after being
driven in.
Rail. Top of bulwarks. 2. Curved timber going from bow to support knee of head.
Rail of the Dead. Name sometimes given to 'Rail 2'.
Raise. To initiate, as 'Raise a bottomry bond'. 2. To cause to appear above horizon, as 'Raise
the land' or 'light'. 3. To dispose rope and blocks in such a manner that a purchase is
obtained—'Raise a purchase'. 4. To sail towards an object so that its altitude increases.
Raise a Purchase. See 'Raise'.
Raise Tacks and Sheets. Order given when tacking a square-rigged ship. As ship moves
through wind, tacks and sheets are kept adjusted so that sail is kept filled and does not go
aback.
Rake. Inclination, in fore and aft line, of a mast, funnel, stem, stern post, or other nearly
vertical member. 2. Inclined shape of after edge of a rudder. 3. To fire projectiles fore and
aft along deck of an enemy vessel.
Raker.* Gun so placed as to rake an enemy vessel.