Naval Tactics (1872 Article)

Naval Tactics was an article that appeared in the first volume of Naval Science: A Quarterly Magazine, etc, which was printed in London, edited by E. J. Reed, C.B..

Article

The term "Naval Tactics" embraces in its widest sense the art of manœuvring ships, whether singly or in squadrons, and whether for the purposes of navigation or warfare. In the present article we propose to give it a somewhat narrower meaning, and to treat it as applying simply to the tactical management of single ships or fleets for the attack upon, or defence against, an enemy. Taken even in this limited sense, however, it is manifest we include the other branches of the subject, as a ship or fleet duly prepared to take its part in the presence of the enemy is, by consequence, fully capable of dealing satisfactorily with all the contingencies of navigation. On the other hand, the limited construction put on the term draws our attention especially to the tactical management of a ship or fleet with a view to the employment in the most judicious manner possible of certain offensive weapons and certain defensive shields. A complete review of the art, as it exists at the present day, would embrace a somewhat closer inquiry into the history of its rise and progress than there is here space to devote to it; but the mind cannot be in a condition for study of this kind which shuts out the historical aspect of the question altogether. We must therefore revert, though only for a very short period, to the state of the art before the inventive genius of the present age had changed its character and complicated the problem set before the naval tactician.

Two causes, which have now quite disappeared, assisted to reduce the tactical developments of our forefathers to a very few simple and clear principles. They were, the limit put upon movement by the wind, and the almost inevitable destruction of all motive power very soon after joining in combat with the enemy. Under such conditions, the single object of the commander of a fleet esteeming himself superior to his enemy, was to close with him by the simplest methods available. Having done this, tactics, properly so called, resigned their office; and it became the affair of individual courage and endurance to conclude what tactics had commenced. These conditions of motion may be said also to have delayed the development of the single naval weapon, the gun, and to have postponed that scientific study of it which is now so universal. Long range, and accuracy of fire, were not objects diligently to be sought for when decisive results were alone expected from close quarters. It would have been a poor satisfaction to two combatants equally impressed with hopes of victory, to find a chance shot had crippled the weathermost, and that the action was practically over before it had well begun. Therefore it remained that until the close of the French war but two modes of laying the guns were known—namely, that aptly called "random-shot," where the piece was given extreme elevation and fired in the air; and the "point blank," where the gun was trained right abeam and horizontal.

Under such conditions, inseparably interwoven, tactics remained broadly simple; and it is impossible to read the works of naval tacticians, whether French or English, who wrote before the advent of steam, without being struck by the elaboration of argument set out to prove that which to a mddern reader seems sufficiently obvious. Yet, again, it must be remarked that some of the broadest principles were controverted points, which remained unsettled at the close of the war, and which are now beyond settlement, because practically obsolete. Such was the attack from to windward or to leeward. The weather-gauge was often painfully sought for by one side for its presumed advantages, and cheerfully surrendered by the other because of its disabilities. The fact seems to be that the weather-gauge gave a convenient vantageground for attack, provided only that the fleet to leeward chose to await it. The leeward position enabled the defending fleet to prevent the weather one closing on it, and always left the road open to escape; as, however crippled a ship might be, she could generally drop away before the wind, while a very slight disarrangement of the rigging would effectually bar an escape to windward. There was, however, one leading principle thoroughly well understood by all combatants at sea—namely, the advantage of being two to one; and if this advantage was less attended to in the practical results of English tactical ideas, it was because the leaders of that age were impressed with the notion that they could well afford to disregard it. The limited motive power forbidding complicated movement, and making it the tactician's object to bring his fleet in a mass, as close as possible to the mass of the enemy, and to leave it there, postponed the necessity for any minute subdivision of the fleet. The only attempted organisation of a body of ships destined to act in company was into three, or less often into two, great masses, and these usually acted in strict concert with each other, if they did not more frequently act as a single mass. An organisation so simple could bear to have its treatment embodied in a very loose terminology without confusion. The three divisions of a fleet were termed the van, centre, and rear squadrons. The two were termed the starboard and larboard divisions. So seldom did it happen that the nominal van, centre, or rear squadrons held positions disagreeing with their titles, under circumstances where the actual and nominal positions could clash, that no error is on record from what might he supposed a prolific source. The starboard and larboard divisions changed their actual positions every time the fleet tacked, yet no mistakes seem to have occurred from the fact. Such things are proofs of the extreme simplicity which surrounded the movements of a purely sailing fleet. Another branch of the terminology was by no means loose: the wind— when there was any—was common to the whole fleet. All terms and all positions involving reference to the wind were perfectly clear, and could scarcely under any circumstances lead to misapprehension, and such terms were universally employed. These things continued almost unchanged in England until a period so recent as 1859. But from the moment steam had asserted its position as the motive power of a war fleet, the doom of the old simple tactics, simple division of the fleet, and loose terminology, was sealed. If it took time to make the change, and if it is yet far from completion, it must be remembered that naval invention has advanced at a rate too rapid to be more than followed. So much was disarranged by steam that its tactical disarrangements only came in for their share of attention, and are consequently still in a somewhat inchoate condition.

If, having thus touched upon the ground occupied by the naval tactics of a former age, we apply ourselves to the study of the modern art, we shall find the problem immensely different from that which must have engaged our attention at the beginning of the century. Then all was fixed; or, if things varied, they did so within close limits, easily ascertained. Now, the object of the tactician is to ascertain whereabouts the limits lie and their extent. He has to build an edifice, yet finds the stones are still unhewn. Should he seek for information on the subject from the writings of others, such as he might have sought for and found on the subject of sailing tactics, he will meet much disappointing vagueness of expression, or, perhaps, even more disappointing strength of assertion; but he will find very little record of fact, very little of experience, very little solid ground wherein to dig his foundation. The very elements being imperfect, his modern science is deplorably doubtful, and while he is called upon to frame an hypothesis, he must do so more in hopes of showing what is wanting, than what is attained, in order to prove its truth.

Passing, then, altogether from the historical aspect of the subject, let us sketch out the nature of the problem presented to the modern naval tactician for solution, and the means at hand, or wanting, to insure the success of that process.

He is presented with an indefinite number of ships, each capable of being propelled in any direction at great speed, but of which some are more capable than others. Each ship has a power of turning under the action of her helm, differing both in time and space occupied, from that of her neighbours. All are more or less coated with an armour which has different degrees of resisting power and is differently distributed. B Such axe his weapon-carriers, the ships. Of weapons he is offered a choice of three, or perhaps four, with the option of employing all if he so chooses. These weapons are the " gun," the " ram," the " Harvey torpedo," and perhaps the " Whitehead torpedo." Out of these elements he must construct such a system of tactics as will put him at the least on an equality with any other tactician, having similar appliances at his disposal, who may choose to meet him with hostile intent on the open sea.

With such data before us, the first thing we shall note, after we have somewhat recovered the natural shrinking from considering at all a problem so complex, is that—unlike the tactician's work in the days of sailing fleets—any choice we may make will immediately re-act on the designer of war-ships. Any one of the four weapons, on being assigned the superior place, will imperatively demand its appropriate carriage, and the tactical system must be designed to deal, not with conditions of things which now exist, but with those which will exist when the change demanded is made. If there were sufficient data to enable us to choose the weapon with certainty, the path of the tactician would be clear enough, and that of the designer equally so. If there are not sufficient data, a course of experiment would be required to obtain it. If from any insuperable cause the data remain insufficient, the tactician may be compelled to frame his scheme, but he cannot have much confidence in its value, and the designer must compromise matters so as to meet the data of the day.

But before coming to a choice of weapons a somewhat easier part of the task may be undertaken. The fleet may be given mobility. If many steam-ships of various speeds and turning powers can be made to move in formation as one or more masses obedient to a single will, that of the admiral, it is certain that uniformity of speed and turning powers will simply enhance the value of the tactical plan so far. It is certain that if ships are to act in concert at all, fleet mobility will be a material element in the tactician's arrangements, whether he adopts the gun, the ram, the Harvey or Whitehead torpedo, or all four weapons together. Therefore the ground is safe and the labour is not lost in proceeding to consider the methods by which a heterogeneous steam fleet is to be made mobile.

Before the admiral can transfuse his will into any given change or motion on the part of the fleet, four separate matters must be pre-arranged. The fleet must be conveniently subdivided; convenient terminology must be adopted; an instrument and system must be designed for translating this terminology into signs capable of immediate transmission to a distance; means must be found for making each ship's naturally heterogeneous movements uniform.

The problem of subdividing an English fleet was somewhat complicated by a natural reluctance to surrender that which had formerly answered so well. A great variety of opinion on the question existed, but the plan adopted by the Government appears to meet all requirements, while being itself very simple. A choice lay, in the first place, in the selection of the tactical unit. .It was possible to fix the unit at a certain small number of ships—three or four—and then, according to the size of the fleet, the units would be more or less numerous. It was also possible to make the fleet itself the unit, so that on subdivision its smallest groups would each contain a larger or a smaller number of ships, according as the fleet were larger or smaller. The first method, which has been adopted in the French Navy, is really subordinate to a particular ideal system of tactics. The second method, adopted by the English Navy, has no ideal system in view, but is no hindrance to any which might hereafter become permanently adopted. According to this plan a fleet, whatever its size, is designed to be divided and subdivided. If very large, it may be divided into as many as four great divisions, each of which is to be subdivided into two subdivisions. If smaller, into three, and if still smaller, into two great divisions; and in each case the subdivision is half a division. Provision is also made for detached squadrons not in the general organisation, though bearing company with the fleet.

The task of framing a new terminology was complicated by the same difficulty which beset the division of the fleet. But at length a system was devised, which, though it almost entirely abrogated the old terms, yet passed into common use with surprising ease, and almost without remark. The difficulty consisted further in this, that all sorts of rapid changes of front were to be calculated on; all kinds of grouping, concentration, and dispersion were to be provided for; yet there was never to be a moment at which any new transformation determined on in the admiral's mind should not be rapidly and clearly understood by the ships concerned. These objects were gained by employing one set of terms with no local signification, which were never used subjectively in any order directing a movement, but only as pointing out to whom any such order was addressed; and another set wholly local in their signification, which were always used subjectively in orders for movements. A name of the first kind, when once assigned to a part of the fleet, never left it, whatever its position might be. A name of the second kind was quitted the moment the position it signified was abandoned. Thus if the "second "division" were at any moment in front of the fleet, it would be called in any order then given "the leading column." If, in consequence of every ship suddenly reversing her course, this " second division" found itself behind the rest of the fleet, it remained " second division," but was now the " rear column." So also whatever group of ships might be on the extreme right of the general formation at any moment, was then known as the " starboard wing column," and any group on the extreme left of the formation was called the "port wing column." The simplification gained by such a terminology, and the clearness of orders conveyed thereby, can only be properly estimated by considering alternative schemes. It is evident that if a certain prescribed order be given to a fleet, different changes of front, and interspersions of the divisions composing it, will cause it to undergo four variations of formation. Thus if the fleet starts with three divisions, each in line-ahead steering the same course, No. 1 on the right, No. 2 next, and then No. 3 on the extreme left, such an arrangement would be called, in alternative language, the "direct order." An immediate reversal of course by every ship would bring No. 1 division on the left, and this would be called "transposed "and reversed order," because each division would be in reversed order as to its ships, and the divisions themselves would be transposed from right to left. Starting again from the direct order, if the headmost ship in each division were to reverse her course and to be followed in that process by each succeeding ship of her division, the result would be that on the opposite course the ships would remain in their first order in their divisions, but the divisions would be transposed. Hence the changed formation would be termed "transposed order." If the whole of the ships were now to reverse their courses at the same moment, the result would be that the ships in each division would be in reversed order, but the divisions would lie relatively to each other as they started. This would hence be "reversed order." It is evident that any order directing a movement conveyed in language involving these four terms must be quadrupled. Its form must be "if in direct order, &c.," "if in transposed order, &c.," "if in transposed and reversed order, &c.," and it may be briefly stated that the conciseness and clearness of the English terminology consists in its avoidance of such forms of words.

A further and necessary change for a steam fleet, was the subordination of terms involving the direction of the wind to such as were independent of it, and this has been carried out in the English Navy with perfect success.

With the method adopted for signifying the admiral's orders to his fleet—the system of signals—we do not intend to deal here. It is a branch of the tactical arrangements which can be studied by itself, and it does not in any way govern what is hereafter to be treated.

We arrive now at the consideration of the means whereby ships of different speeds and different turning powers may be made to manœuvre uniformly. As to speed, it is obvious that the slowest ship in a fleet governs its movements, and restricts them to a rapidity easily attained by her. It is not quite so obvious, but it will be presently shown, that the ship with the worst turning powers also limits the manœuvres of the fleet in which she finds herself.

In any assembled fleet the first thing is therefore to know the slowest ship, and what her maximum speed is. Such information is generally at hand, either from the recorded trials at the measured mile, or at sea. A speed well within the ascertained maximum may then be taken as the manœuvring speed of the fleet, bearing still in mind that the higher the speed, the more rapid and the more easy are the manœuvres. It does not appear to be supposed that a speed of more than ten knots can be calculated on in a modern fleet, while leaving a sufficient reserve for contingencies. The speed being established, each ship must ascertain the number of revolutions of her screw corresponding to that speed, and which she must maintain while in company with the fleet and while manœuvring. This also is easy of ascertainment from the already recorded conditions of the ships. A very short period of steaming in company will then rectify any errors of calculation, and if the admiral maintains a fixed number of revolutions known to the whole fleet, a close uniformity of speed is soon established.

Uniformity of turning, both as to time and space, in the existing state of knowledge, is more difficult of attainment, but there is not the slightest reason to suppose it cannot be thoroughly established in the most heterogeneous fleet likely to be assembled. But more information . requires to be recorded before the method can be definitely prescribed.

We have already said that the necessity for this uniformity is not so obvious as that for uniformity of speed; this is almost proved by the existing deficiency of means to secure it. On the other side it is known that on many occasions the greatest fears have been expressed on the danger of placing long and short ships together in one squadron, yet it is quite certain that such danger can only arise from the unequal times and spaces occupied by the ships in turning.

The solution of the question depends on an accurate knowledge of the behaviour of steam-ships under the action of their helms, and this is almost completely wanting. Neither in England nor in any other country do the materials exist for establishing the exact relations between space and time occupied in turning, the speed, and the helm angle. All that is known accurately is that within the limits of experiments already tried there is for every ship a maximum power of turning, which is attained when the highest speed is combined with the largest helm angle. The ship then turns in the shortest time and in the smallest space of which she is capable when the two are combined. If the helm angle be diminished, both time and space are increased; if the speed be diminished, the space may be diminished also, but the time will be increased. That which concerns the mobility of a fleet most nearly is the ratio of time, space, and helm angle. It seems certain that the time does not vary inversely with the helm angle, or directly with the radius of the arc described, but at a much slower rate. Such meagre experiments as exist have tended to show that for the higher helm angles—which are the important ones—the radius of the arc described varies inversely as the sine of the helm angle, and the time directly as the cosine. The importance of investigating this subject thoroughly — which might easily be done with ships now in commission—may be judged from the fact that there are ships together in one squadron whose times of turning and spaces are nearly as 1 to 2. In making the simple turn through eight points of the compass it will occupy one ship two minutes, and another one, while their relative positions at the end of the movement will differ by several hundred yards from those occupied before it.

In the absence of any satisfactory theoretical data, ships brought together in a fleet must measure their arcs of turning at the appointed speed, and must then by actual trial ascertain for each ship, what less amount of helm than that capable of being given by the worst turning ship in the fleet will cause her to turn on the same arc. There will remain, in manœuvring, the differences of time due to differences of helm angle, but so far as experiment has yet gone, these are so small that they are of no practical importance.

When all the foregoing steps are taken, the fleet is completely mobile; and it only remains to set out in order the kind of movements either useful for training the nerves and eyes of those who command in the fleet, or likely to be put in force in presence of the enemy. There is a broad classification of fleet movement which it is important always to bear in mind. It is generally possible to make any required change in formation either by alteration of helm alone, or combined with alteration of speed. Considering the enormous mass of present ships, variations of speed must occupy time; we know they vary the arc of evolution; we can suppose that neither theory nor practice will ever enable us to vary the speed exactly at the right moment, and to the required amount. Hence it is that movements depending on the helm alone are much simpler and very much safer than those requiring both helm and speed to be dealt with. It happens also that this class of movement is much quicker than the other. Take, for instance, the transference of the "line ahead"—where the ships are ranged ahead of each other—into the "line abreast," where the ships are ranged side by side. If the helm only is used, the headmost ship turns off to the right or left, and is followed by each ship in succession. The rear ship does not turn, but just before she reaches her turning point the whole line resumes its original course. The time occupied by the movement is exactly that taken by the rear ship to traverse the length of the line. Attaining the same end by both helm and speed, the headmost ships must reduco their speed, while the rearmost press on across the hypothenuse to their places on the extreme left or right of the line. The time occupied here is measured by the power the headmost ship has of reducing and the rearmost of increasing her speed. When the normal speed is very low this power is considerable; but when, as must be the case in actual warfare, it is high, the time occupied is indefinitely prolonged. The movements by helm alono are generally known as "rectangular" movements. Some controversy still exists about them, but their advantages may safely be left to the test of experiment. We have thus dwelt at some length on the principles of fleet mobility, because it is a part of tactics completely within our power to develop. We have all the means at hand for moving a steam fleet, however heterogeneous, in the closest order and like a single machine; but we want for that purpose clearer knowledge of the laws which govern the action of the helm, and that can be ascertained by patient experiment with existing ships. Having made the fleet mobile, the student is brought face to face with the grand difficulty of modern naval tactics, the choice of weapons. What would be the English choice, should war come upon us now? It is somewhat painful to note that we have no choice. We vaguely hope that a wise choice will in some way be disclosed to us, and we do not take a great deal of trouble to see how things now point. The position we hold is dangerous and improper. Dangerous, because our condition of mind may be taken advantage of. Improper, because we have it in our power to try those experiments which would lead to a sound choice. While each of the four modern naval weapons, the gun, the ram, the Harvey torpedo, and the Whitehead torpedo, has its advocates, who are strong and persevering in proportion to their single-mindedness, the great mass of naval men simply look on. But there are some points on which a combination of circumstances has caused the naval world to make up its mind. The gun is a known and tried weapon. The ram has also been successfully used in warfare, and its place as a weapon which may again be used is secure. Therefore a ship or fleet must not expose itself to be rammed if it can be avoided. The conditions of exposure to this form of attack are a broadside position and low speed. To be found by an enemy with either of them is dangerous; with both, fatal. The maintenance of the broadside position as opposed to the end-on has therefore passed away. But the gun is also a known weapon. If the necessities of avoiding the ram demand the end-on position, the gun must be fought in that way. Hence there is an overwhelming demand for strong bow fire. It is, however, argued by a minority in England, but possibly by a majority in France, that in the demand for bow fire, speed, as one of the conditions, has been overlooked. It has been pointed out that if two fleets are coming into action at the speed of ten knots, with their bows towards each other, there are only three minutes during which their bow artillery can be profitably used. And the French authorities have laid it down in so many words that, under such circumstances, "an armoured vessel cannot "do better than impose silence on her artillery." It must be observed, also, that those who uphold the value of bow fire do so on pure conjecture. No experiments exist from which its value may be estimated. All that is really known is that its accuracy is much reduced from that of fire at fixed range by the enormously rapid alteration of distance; and that from the angular nature of the target presented to it, its penetrative power is also reduced. This is one of the questions referred to before as capable of solution, and it is evident it ought to be solved. All that is required is the construction of a canvas screen target, representing the midship section out of water of a modern iron-clad. This should be dropped at sea, and fired at by a ship or ships approaching it at various speeds. A few days' practice would show the actual value of bow fire, and whether other nations are mistaken in their low estimate of it. It may be observed that as yet we have no data for the value of fire at fixed ranges at sea, but to some extent this is in course of supply, and it is not so vitally important to know as that of bow fire at varying range. Tt is held by the French tactical authorities that the necessity for an end-on method of approach to the enemy has abolished the value of the rectangular movements, but the argument does not appear to be sound. For the value of the rectangular movement is its simplicity and its speed. The assumption of the end-on position is in no degree necessary unless the enemy be so near as to be able to take advantage of its absence. But this distance is so small that no manœuvres whatever could then be undertaken. On the other hand, with an enemy rapidly approaching, the utmost celerity must be given to any change of movement or formation. To do by a slow method what can be done by a swift one would be a fatal error.

The gun and the ram being alone considered, three modes or forms of attack are before us. There is the approach in an extended front whose value depends on the supposition that bow fire is valuable; that ramming may take place, stem to stem; and that a ship to ship encounter in a sort of milee is to be the ultimate result of a naval encounter, where, as of old, the stalwart Englishman may show his peculiar prowess. There is, again, the system of isolated attack, the peculiar growth of the age, which assumes the reverse of concentration as its basis. In this attack the fleet approaches in a number of semi-independent groups of three or four ships each. In command of each group is placed an officer specially calculated to lead well, and he is left with his hands untied to attack that part of the enemy, or support that part of his own fleet, which seems weak. This method also seems to assume a melee, but yet sufficiently open and free from smoke and confusion to allow of much intermanœuvring between the fleets. It has never been critically examined or pushed to its probable consequences by its supporters, and to do so here would occupy too much space. It is held in great esteem by the French authorities.

Quite recently another principle of attack has been partially developed. This assumes the end-on position as an effectual defence against rams; it holds bow fire valueless, and supposes a broadside fire discharged in passing at speed, and at close quarters, is the really effective weapon of the present day. It further holds that modern fleets will not become entangled in passing; that there will be no melee until the victory begins to declare itself. On such hypotheses the attack is made in a formation with a narrow front and great depth. If opposed to an extended front, it pierces it, or passes by its flank ship after ship, in the closest succession, discharging broadsides from fresh ships into the same ships of the enemy. It thus represents the principle of "doubling on the enemy," but it is done in succession in lieu of simultaneously. The idea of this attack is extreme concentration, and it is supposed the fleet will reform in rear and advance again on the fleet it has passed through.

It is manifest that the values of these three modes of attack can be properly demonstrated only by experiment. The value of the bow fire of a fleet can be tried as described. The possibility of maintaining an extended front and keeping up a fire is doubted; it also can be determined easily, but only, by experiment. The possibilities of the ram and the practice of ramming can also be studied experimentally, the first by large ships upon targets, the last by gun-boats arranged with proper buffers. These are all things to our hands: by their means our knowledge would become accurate, and we should with confidence adopt that method of approach upon the enemy when he appeared, which we are aware beforehand is the best.

The effect of the sea torpedo on the development of naval tactics is difficult to estimate. A tendency to underrate its power is perhaps as prevalent as the opposite bias. It cannot, however, be omitted to note that as yet all the ingenuity of the inventive mind has been exercised on the torpedo attack: little or nothing has been done on the side of defence, and we must by no means forget that the latter is to come. The Harvey torpedo, used in an ordinary sea-going ship, has been held to be a good defence against a ram; and it is supposed that its effect in single combat would be to reduce it to a battle of guns. In fleets—as the torpedo at present exists—it is somewhat dangerous to neighbouring ships, although not enemies. Used generally in a fleet, it does not appear to influence the formation, but it would probably prevent the cutting of an extended line.

The Whitehead torpedo is so new, and as yet so little known, that its influence on tactics is quite in the haze. Whether it be discharged from the bow or the broadside, however, it is essentially a submarine gun, and the strong probability is that its tactics will harmonise perfectly with its representative above water. So wide, so intricate, and so dubious a subject as the tactics of modern navies could never be satisfactorily treated in a single article. We have thought that a slight outline of the whole case, as it now stands, would be a more fitting opening than a more elaborate examination of any one part of it. The object has been to show all the varieties of opinion which exist, and to suggest means by which they might be confirmed or destroyed. There is hardly any branch of Naval Science which more loudly demands experimental treatment.