SIGNALS, MARINE. :Marine signals now in current use may be divided into three classes: (a) Day signals, (b) night signals, and (e) day and night signals. Day signals consist of set combinations of flags or shapes, moving com binations of arms or shapes, or the waving of shapes or flags. The use of flags of various shapes is wide-spread, and is of ancient origin; the Venetians used such signals, and there is good reason to believe that simple signals of this sort were used in very ancient times. In I856 the British Government devised a system of sig naling by flags which has been adopted by all maritime nations. It formerly consisted of thir teen square flags, five triangular pennants, and a swallow-tail flag. One of the pennants was the code pennant; the other pennants and flags were assigned to the consonants of the alphabet from b to w. On January, 1901, by international agreement, a new code went into effect. It con sists of nineteen square flags, two swallow-tail flags, and five pennants besides the code or an swering pennant. These are assigned (except the code pennant) to the different letters of the alphabet. The flags and pennants of the old code are retained with few changes, the new ones being additional to cover the vowels and x and z. The flags and pennants are hoisted singly or in combinations of one, two, three, or four. One-flag signals are important in character and much used; two-flag signals are urgent and important ; three-flag signals include all ordinary messages; four-flag signals signify geographical positions (seaports, islands, bays, etc.), alphabetical spell ing tables, and vessels' distinguishing numbers. The signification of each combination of flags is the same in all languages, each combination stand ing for a complete message, a sentence, a phrase, or a single word. A vessel using a signal book printed in English can communicate with a ves sel using a book printed in Italian as easily as with one using an English book.
The spelling table may be used between ves sels having books printed in languages using Roman characters. The American edition of the international signal code is published by the Ilydrographie Office of the Navy Department, and is divided into three parts. The first con tains urgent and important signals, signals for tables of money, weights, etc., for geographic
positions (arranged geographically), and a table of phrases formed with auxiliary verbs. The second part, which includes more than half the book, is an index. It consists of a general vocabulary and a geographical index. each al phabetically arranged. The third part gives lists of the United States storm-warning„ life saving. and time-signal stations, and of Lloyd's signal stations throughout the world; it also contains semaphore and distant signal codes and the United States Army and Navy and Morse wig wag codes.
In the United States Navy the general code consists of ten rectangular flags, corresponding to 0, 1, 2, 3, 4. 5, 6, 7, S. and 9; also a number of special flags, pennants. etc. In most other navies the flags of the international code are utilized.
The use of shapes is common for distant sig nals, as the colors and patterns of flags cannot he determined with certainty beyond two or three miles. These shapes are cones. halls, and drums, supplemented with a square flag and a pennant. The placing of movable arms in certain positions is termed semaphore signaling. Devices for sem aphore signaling have been in use foi some centuries at least; they were called telegraphs and were placed in sight of each other to form long chains of communication across country. The modern semaphore has two or three arms, and its use is chiefly at signal stations on the coast or on board ship. In most navies a simple semaphore code is arranged for two small flags, one to be held in each hand of the signalmen. In the United States and British navies there are seven positions—in the French navy, eight. These po sitions of the first named are: Right arm M dined downward at angle of 45° : same, horizon tal: same, inclined upward at angle of 45°; three of the remaining positions are for the left hand at 45° downward, 45° upward, and horizontal; the remaining position is either arm held ver tically. In the French code, the right arm held vertically is one position and the left arm held vertically is another. In both codes the combi nation of any two positions is used in addition to the simple positions. In the United States Army and Navy the wig-wag code is used as described SIGNALING AND TEL EGRAPH I NG. MILITARY.