COLLISIONS A.ND SIGNALLING AT SEA.

ATE. of science are deeply, and with good resaon, interested at present in the Telephone, the most remarkable in some respects of the many remarkable developments of telegraphy, or the art of signalling from a distance. But there is a problem of signalling only to be dealt with by the earlier and simpler methods, which still remains, if not unsolved, at least left practi- cally unanswered. Means of communication between vessels at sea undoubtedly exist, and under favourable conditions ships may communicate by the existing code with tolerable facility. But we have had, even during the last few months, sad evi- dence of the insufficiency of these means under unfavour- able conditions, and sometimes even when the condi- tions seemed favourable enough. Collisions have occurred through the misapprehension by one captain of the course followed by the other, and this where there was ample time for the interchange of information. Seamen are apt to laugh at the mistakes made by landsmen as to the object of a ship's manceuvres. A ship standing in one direction will to the Iandsman's ideas seem manifestly intending to reach one particular point, whereas it will be obvious at once to a seaman's eye that the intention is to reach a point in a nearly opposite direction. Every one remembers the fine description in Reade's "Christie Johnstone " of the saving of Gatty,—' " The boat is not going to the poor man,' says Gatty's mother, not knowing who is in danger, ' it is turning its back upon him.' She canna lie in the wind's eye,' answers a fishwife, for as clever as she is.' " But even the most experienced seaman sometimes misapprehends the manceuvres of a distant vessel. He may mistake for some specially neat stroke of seamanship a very simple manceuvre, or else a manceuvre which appears to him simple may have been intended to result in some masterpiece of nautical strategy. Be the cause what it may, mistakes have been made, and only too frequently the result has been that a collision has occurred which might easily have been prevented, sometimes even a collision which would have seemed practically impossible. The means of conveying by signalling the purpose of a com- mander or the intention of some special manceuvre are at present clumsy in the extreme, and altogether ineffective where time presses. Three flags in a vertical line represent severally three letters, and on reference to the signal-code the message corre- sponding to these three letters can be ascertained. That message conveyed, another may be sent off, by running down the three flags and running up other three, or the same three in another order,—a process requiring time. But this is not the worst point of the present system. To be well seen, the flags should stand out stiffly, as they do in a steady breeze, but as they do not do when light variable winds are blowing. They should be at right angles or nearly so to the line of sight from the distant ship, which they may be or may not be, .according to the direction of the wind. If either ship is before the wind, and sailing nearly towards the other, the signal flags of neither will be visible from the other. If she is sailing close to the wind, and her course is such as would bring her nearly -athwart the other, somewhat to leeward, the signal-flags will not be well seen from either ship. Then one flag can readily be mis- taken for another, unless seen under exceptionally favourable con- ditions. For instance, the letter P is represented by a square blue flag with a white centre, the letter W by a square blue flag with a somewhat larger white central space, in the middle of which is a small square of red. In a light, variable wind, these two flags, even at a moderate distance, could easily be mistaken for each other, and the consequences might be very serious. It is clear also that flag-signalling is only available in the daytime.

A plan has been devised called the Stellar-Abacus system, by which not only might the risks above described be avoided, but messages might be much more quickly signalled than by the pre- sent system, and as readily at night as in the daytime. Its author, Mr. A. Stewart Harrison, is known, or ought to be known, as the inventor of a modified form of the bayonet, by which it can be made available as a spade,—a plan which (reinvented, we pre- sume, by a Russian) has recently been adopted by the Russian Army. The stellar abacus is simply an oblong black-board, on which, as on a background, there are eight metallic discs, in two rows of four, besides a single disc at the top. Any number of either row of four discs can be shown or covered in an instant by bars sliding along the length of the board, and the top one can be covered singly, if required. The letters are in- dicated by the number only, not by the position, of discs visible in each row,—an important point, because if position had to be noted mistakes might readily arise. For the vowels a, e, i, o, u, only the top disc and discs on the left-hand column are shown, the top one alone for a, the top one with one, two, three, and four left-hand discs for e, i, o, and u, respectively. For the first four consonants, b, c, d, f, the signal is one, two, three, four discs respectively on the left, and none on the right. For the next four consonants, g, h, j, k, one, two, three, four discs respectively on the left, and one on the right. For the next four consonants, m, n, p, one, two, three, four balls respectively on the left, and two on the right. For q, r, s, t, one, two, three, four balls respectively on the left, and three on the right. In all these cases the single disc at the top, forming with the two uppermost of the side-discs an equilateral triangle, remains in view. For v, w, y, one, two, three balls respectively on the left, and four on the right, the single upper one visible : for x and z the same .as for w and y, but the single upper one hidden. We have been thus particular in describing how each letter is formed, that the simplicity of the method may be recognised. The signals for the word " spectator" would be as follows :—

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S P E C T A T 0 R.

But while the abacus can thus be readily used to spell out a short message letter by letter, it can of course be still more advan- tageously used with the ordinary code of signals, three letters giving, on reference to the proper place in the book, a complete .message. The advantage, however, of being able to communicate without reference to the book, in cases of emergency, will be manifest.

In the daytime, the discs of the abacus would be readily seen, —far more readily, for instance, than the flags of the present system, even when the wind displays the flags best. For the 'black-board with its white discs can be presented full-front -towards the ship to be signalled. The change of letter can be effected in a moment, by simply pulling down or pushing up the sliding-bars to the required amount. At a distance, or in weather when the flags would be useless, the well-defined black disc could be easily seen with the naked eye, and the discs would have a still more decided advantage over the flags at distances great enough to render the use of a telescope necessary. At night flags are useless, but the discs could be well displayed either by transmitted or reflected light. For the former, they would be simply glass-covered round holes, and a light behind would shine through such of them as were left uncovered by the sliding-bar. For the second, they would be of some metallic substance of good reflective qualities, as bright tin, an arrangement which would, on the whole, be simpler than the other. But we need not further consider details such as these. It is manifest that the method is simplicity itself, and that it might be carried out in a number of simple ways. A signalling-board could, in fact, be prepared in a few minutes by the ship's carpenter, if none were ready at the moment. And the signal-alphabet could be learned in five minutes by any intelligent lad.

Some doubts may be suggested as to the separate visibility of the white discs at considerable distances. But from what has been shown in experiments made by astronomers on the separa- tion of artificial double stars, and especially by the researches made into this question by M. Otto Struve, the Russian Govern- ment astronomer, at Poulkowa, it is certain that if the black-board had even dimensions considerably less than the three flags of the pre- sent method of signalling, the discs would be separately discernible either to ordinary or telescopic vision (according to distance) when the signalling-flags would be barely recognisable.

The method of signalling by the stellar abacus is one that could be conveniently used for other purposes than communi- cation at sea. But we prefer to consider specially here the one purpose which the system seems able to subserve most effectively. For military purposes, apart from ordinary telegraphic (and we suppose we must now add telephonic) methods, many modes of signalling can be adopted. But at sea, and especially under those conditions which render collision pro- bable or possible, only methods possessing certain characteristics, as extreme simplicity, clearness, convenience of arrangement, and so forth, are available. It is certain that the method of signalling at present employed is liable to fail. We have had repeated instances of this during the last few months. Loss of life and loss of property have resulted from collisions of which a con- siderable proportion might have been prevented, had the means of ready communication been available. It appears to us that as a tribunal exists which can assign punishment to the cap- tains and officers of ships when collisions or wrecks have occurred from neglect of proper measures for preventing them, so these tribunals themselves, and all persons officially respon- sible for the safety of our seamen from preventible accidents, should be amenable to judgment before a higher tribunal—the tribunal of public opinion—if they allow reliance to be longer placed on methods of communication at sea which have failed disastrously under conditions likely to be of frequent occurrence.