Signals

a system of communicating, especially at sea. In 1902 a new international code was adopted superseding all previous ones. Two swallow-tailed pennants are used for the letters A and B. Five triangular pennants of different colors are used for the letters C to G; nineteen other flags readily distinguished are used to complete the alphabet. It is possible to spell out any word or message by displaying these flags in proper order. A very great number of signals have been agreed upon, however. C displayed alone means, "Yes"; D, "No"; A hoisted over B signifies "Abandon your ship at once." One combination asks whether icebergs have been seen; another, whether water can be spared; another indicates a desire to send a message, etc. Other combinations of two and three flags afford several thousand possible signals, any of which may be read by the use of the international code book with which each ship is provided. A similar system of conveying information is familiarly spoken of in military service as "wig-wagging." In such cases, the utmost secrecy is observed, of course, and the meaning of signals is changed frequently.