Though the Morse system has its place, as we have seen, in the drill of our blue-jackets, it does not altogether meet naval requirements. A man waving flags on board ship would be a scarcely conspicuous enough object, and intermediate vessels in a squadron would block out all view of him from those farthest off, hence naval communications are ordinarily made by means of flags exhibited from the mast head or other clearly visible position. Instead of one flag being used, our men-of-war have over forty, and these are all conspicuously distinct from each other. The messages are not spelt out, as in land operations, but the flags are used in various combinations, and the meaning of the signal is found by reference to a {130} code-book. These flags, it is arithmetically evident, can be transposed and grouped in some thousands of different ways, and the code-book contains questions and answers to meet the very varied requirements of naval service, and the special signal hoist for each. The first real attempt at sea-signalling was made during the reign of Charles II., when a series of signs of the most arbitrary character was devised, consisting for the most part of flags hoisted in various parts of the ship, and altering their significance as their locality was changed. The system was a very cumbrous one, and in 1780 Kempenfeldt, the Commander of the ill-fated _Royal George_, improved to some extent upon it, but even then the result was not very brilliant. Lord Howe, in 1792, could only make a total of one hundred and eighty-three signals. As yet, however, it had never struck anybody how much simplicity and advantage would be gained by employing numbered or lettered flags, and then using them in the thousands of combinations that such a system rendered possible. It is stated by various authorities--and even authorities have a way of copying from each other--that flags were numbered for the first time about the year 1799, but in the Library of the Royal United Service Institution may be seen "An Essay on Signals, by an Officer of the British Navy," bearing the date 1788.[85] The flags were numbered 1, 2, 3, 4, 5, 6, 7, 8, 9, and 0, and they are represented in our illustrations by Figs. 287, 288, 289, 290, 291, 292, 293, 294, 295, and 296. It will be seen that they are all of a very clear and distinct character. When such a number as 444 was required, it would appear to be necessary to have three flags like Fig. 290--the No. 4 of the series--but to avoid this multiplication of identical flags, a red triangular flag called a decimal, a white triangular called a centenary, and a blue triangular called a millenary, were used, and these were placed as required before the unit to be repeated. By this plan 444 would be expressed by the yellow flag, the No. 4, having below it the red and white pennants. Sometimes these flags really meant numbers, and then the required number was hoisted, plus a yellow swallow-tailed flag. Thus in answer to