But the need for other and lighter ships "meant for other uses" and not "fit to lie in a line," is equally demonstrable. The function of battleships is to act in concert. They must therefore be concentrated in fleets sufficiently strong to give a good account of the enemy's fleets opposed to them. This does not necessarily mean that all the fleets of a belligerent must be concentrated in a single position. But it does mean that if disposed in accordance with the dispositions of the enemy they must be so disposed and connected, that, moving on interior lines, they can always bring a superior force to the point of contact with the enemy. Subject to this paramount condition, that of being able to concentrate more rapidly than the enemy can, dispersal of naval force—not of units but of organized fighting fleets—is generally a better disposition than extreme concentration. But it is a fatal error in strategy so to disperse your fleets as to expose them to the risk of being overpowered by the enemy in detail.
The fleets of capital ships thus organized, and disposed as occasion may require and sound strategy dictate, are not, however, by any means to be regarded as autonomous and self-sufficing organisms. They are rather to be regarded as the moving base of a much larger organization, much more widely dispersed, consisting of lighter vessels not fit to lie in a line, but specially adapted to discharge functions which capital ships cannot as such discharge, yet which are indispensable either to the full efficiency of the latter or to the maintenance of an effective command of the sea. The first of these functions is the collection and rapid transmission of intelligence as to the enemy's dispositions and movements over as wide an area of the waters in dispute as is compatible with communication rapid enough to allow of counter-movements being made before it is too late. The development of wireless telegraphy has largely extended this area, but it is not without limits in practice, and those limits are already narrower than the extreme range of a single transmission by wireless telegraphy. For example, a warship in the Levant might, if the conditions were exceptionally favourable, communicate by direct wireless with another warship in the Orkneys. But the information thus transmitted would hardly be likely directly to influence the movements and dispositions of the latter. If it did it would probably not be through the immediate initiative of the Admiral commanding in the North Sea, but through the supreme control of all the naval forces of the belligerent affected, exercised through the General Staff of the Navy at the seat of Government. It may here be remarked in passing that the development of wireless telegraphy will probably be found in war to strengthen this supreme control and to weaken to that extent the independent and isolated initiative of individual Commanders-in-Chief. But that is not necessarily a disadvantage, and even so far as it is disadvantage at all it is more than balanced by the immense corresponding advantage of keeping the War Staff at all times in direct touch with every part of the field of naval operations, and thereby making it the focus of all available information, and the directing authority for all the larger strategy of the campaign. Except in degree, moreover, there is nothing new in this. When Nelson was returning across the Atlantic, after chasing Villeneuve out of the West Indies, his only way of informing the Admiralty of the nature of the situation was to send on Bettesworth in the brig "Curieux" with his news. Nowadays a modern "Curieux" would be able to send on the news as soon as she came within fifteen hundred or possibly two thousand miles from the British Isles, and Nelson at the same distance might have received his orders direct from the Admiralty. But the special point to note is that as soon as Bettesworth's information was received at the Admiralty, Barham, the First Lord of the Admiralty, instantly issued orders which profoundly modified the dispositions of the fleets engaged in blockading the French ports and led directly to Calder's action off Finisterre, and in the sequel to the abandonment by Napoleon of all his projects of invasion and the destruction of the allied fleets at Trafalgar. There were giants in those days both afloat and ashore. But the giants afloat did not resent the interference of the giants ashore, and, as Mr Corbett has shown, the Trafalgar campaign was conducted with consummate sagacity by Barham, who embodied in himself the War Staff of the time.
Such is the transcendent importance of intelligence, and of its collection, transmission, collation, interpretation, and translation into supreme executive orders. Its collection and transmission is mainly the function of cruising ships disposed either individually or in small groups for the purpose, and at such a distance from the main body of battleships as is not incompatible with the movements of the latter being controlled and directed, either by their immediate commanders, or by the War Staff at the centre, according to the information received from the outlying cruisers. Such cruising vessels may vary in size and strength from the modern battle-cruiser, so heavily armed and armoured as to be not incapable of taking a place, on occasion, in the line of battle, down to the smallest torpedo craft which is endowed with sufficient enduring mobility to enable her to keep the sea and to cruise as near as may be to the enemy's ports. I have already indicated the other collateral functions which will have to be discharged by torpedo craft in case of a blockade and pointed out the vital distinction which differentiates them from the small craft of the past in that in certain circumstances they are capable of taking a formidable part in a fleet action even as against the most powerful battleships. But we are here considering them solely from the point of view of their cruising functions, whether as guarding their own shores or watching those of the enemy with a view to fighting on occasion and to observation at all times. Their supports will be cruisers of larger size, disposed at suitable distances in the rear, and themselves supported in like manner by successive cordons or patrols of cruisers increasing in size and power, until we come to the battle fleet as the concentrated nucleus of the whole organization. This is merely an abstract or diagrammatic exposition of such an organization, and it is of course liable to almost infinite variation in the infinite variety of warlike operations at sea, but it serves to exhibit the rationale of the differentiation of naval force into battleships, cruisers, and small craft.
It has sometimes been argued that, inasmuch as the torpedo craft is, or may be, in certain conditions, more than a match for even the biggest battleship, battleships together with all intermediate ships between the battleship and the torpedo vessel, are not unlikely to be some day regarded as superfluous and in consequence to be discarded altogether from the naval armament of even a first-class maritime Power. It is true that the range and accuracy of the torpedo have latterly undergone an immense development, so that a range of even ten thousand yards or five sea-miles is no longer beyond its powers. It is true that the development of the submarine vessel has vastly intensified the menace of the torpedo and it may soon be true that the development of aircraft will add a new and very formidable menace to the supremacy of the battleship. But except for this last consideration, which is at present exceedingly speculative, a little reflection will disclose the underlying fallacy of arguments of this kind. The enduring mobility of the torpedo craft is necessarily limited. It is incapable of that wide range of action which is required of warships if they are to establish and maintain any effective command of the sea. It is exceedingly vulnerable to ships of a larger size, and of more ample enduring mobility. These again will be vulnerable in their turn to ships of a still larger size and thus the logic of the situation brings us back to the battleship once more with its characteristic functions. It may perhaps be urged that this chain of argument takes too little account of the submarine vessel which is at present singularly invulnerable because for the most part invisible to any vessels, whether big or little, which operate only on the surface and even if discovered betimes by the latter, is not very readily assailable by them. But of two things one. Either the submarine vessel will remain small and therefore weak, and lacking in enduring mobility, in which case it can never establish and maintain an effective command of the sea. Or it will grow indefinitely in size, in which case it will fall under the inexorable stress of the logic which brings us back once more to the battleship. It may be that the battleship of the still distant future will be a submersible battleship. But many exceedingly complex problems of construction and stability will have to be solved before that consummation is reached.
Lastly, the specific function of the so-called battle-cruiser would seem to need some further elucidation. At first sight this hybrid type of vessel might seem to be an anomalous intrusion into the time-honoured hierarchy of battleship, cruiser, and small craft, which the ripe experience of many wars, battles, and campaigns had finally established in the last golden days of the sailing ship period. It is indeed held by some high authorities that the battle-cruiser is in very truth a hybrid and an anomaly, and that no adequate reason for its existence can be given. In face of these opinions I cannot presume to dogmatize on the subject. But some not wholly irrelevant considerations may be advanced. The battle-cruiser is, as its name implies, a vessel not only fitted by the nature of its armour and armament "to lie in a line," whenever occasion may require, but also exceedingly well qualified by its armour and armament, and still more by its speed, to discharge many of the functions of a cruiser either alone or in company with other cruisers. In this latter capacity, it can overhaul nearly every merchant ship afloat, it can scout far and wide, it can push home a vital reconnaissance in cases where a weaker and slower cruiser would have to run away if she could, it can serve as a rallying point to a squadron of smaller cruisers engaged in the defence of this or that vital line of communication, and alone or in company with a consort of the same type it can hold the terminal and focal points of any such line against almost any number of hostile cruisers inferior in defensive and offensive powers to itself. Such are its powers and capacities when acting as a cruiser proper. But it may be thought that in the stress of conflict it will have very little opportunity of displaying these very exceptional powers because an admiral in command of a fighting fleet will never, when anticipating an engagement with the enemy, consent to weaken his fighting line by detaching so powerful a unit for scouting or other cruising purposes. That is as it may be. It will depend on many circumstances of the moment not to be clearly anticipated or defined beforehand; on the strength of the enemy's force, on the personality, sagacity, and fortitude of the admiral—whether he is or is not a man of the mettle and temper ascribed to Nelson by Admiral Mahan in a passage already quoted—on the comparative need as determined by the circumstances of the moment of scouting for information, of cruising for the defence of trade, or of strengthening the battle line for a decisive conflict to the uttermost extent of the nation's resources. It is unbecoming to assume that in the crisis of his country's fate an admiral will act either as a fool or as a poltroon. It is the country's fault if a man capable of so acting is placed in supreme command, and for that there is no remedy. But it is sounder to assume that the admiral selected for command is a man not incapable of disposing his force to the best advantage. "We must," said Lord Goschen, on one occasion, "put our trust in Providence and a good admiral." If a nation cannot find a good admiral in its need it is idle to trust in Providence.
It remains to consider the function of the battle-cruiser in the line of battle. The lines of battle in former times were often composed of ships of varying size and power. There was a legitimate prejudice against ships of excessive size, although their superior power in action was recognized—we have the unimpeachable testimony on that point of Nelson's Hardy, a man of unrivalled fighting experience to whom Nelson himself attributed "an intuitive right judgment"—because they were unhandy in manœuvre and slow in sailing as compared with ships of more moderate dimensions. But except for difficulties of docking—a very serious consideration from the financial point of view—hardly any limit can be assigned to the size of the modern warship on these particular grounds. Quite the contrary. Other things being equal, the bigger the ship the higher the speed, and it is well known that ships of the Dreadnought type are as handy to steer as a torpedo boat. For tactical reasons, moreover, it is not expedient to lengthen the line of battle unduly. Hence there is a manifest advantage in concentrating offensive power, as far as may be, in single units. On the other hand, the experience and practice of the eighteenth century showed conclusively that there was also a distinct advantage in having in the line of battle a certain number of ships which, being smaller than their consorts, were more handy and faster sailing than the latter. The enemy might not want to fight. Very often he did not, and by crowding all possible sail he did his best to get away. In this case the only way to bring him to action was for the pursuing admiral to order "a general chase"—that is, to direct his ships, disregarding the precise line of battle, to hurry on with all possible sail after the enemy so that the fastest ships of the pursuing fleet might bring individually to action the laggards of the retreating fleet and hold them until the main body of the pursuing fleet came up. In this case the retreating admiral must either return to the succour of his ships astern and thereby accept the general action which he sought to avoid, or abandon his overtaken ships to the enemy without attempting to rescue them. Hawke's action in Quiberon Bay and Duncan's action off Camperdown are two of the most memorable examples of this particular mode of attack, and their brilliant results are a striking testimony to its efficacy. If ever in the naval battles of the future it becomes expedient for an admiral to order a general chase, it stands to reason that ships of the battle-cruiser type will be invaluable for the purpose. Their speed will enable them to hold the tail of the enemy's line, and their power will enable them to crush it unless the retreating admiral who seeks to avoid a decisive action turns back to succour such of his ships as are assailed and thereby renders a decisive action inevitable.
There is, moreover, another function to be assigned to the battle-cruiser in a general action, and that is a function which was defined once for all by Nelson himself in the immortal memorandum in which he explained to his captains the mode of attack he proposed to carry out at Trafalgar. "I have," wrote Nelson, "made up my mind to keep the fleet in that position of sailing ... that the order of sailing is to be the order of battle, placing the fleet in two lines of sixteen ships each, with an advanced squadron of eight of the fastest sailing two-decked ships which will always make, if wanted, a line of twenty-four sail, on whichever line the Commander-in-Chief may direct." Owing to the lack of ships this disposition was not adopted on the day of Trafalgar, but the principle involved is not affected by that circumstance. That principle is that a squadron of the fastest sailing ships in the fleet was to be detached from the two fighting lines entrusted with the initial attack, and reserved or "refused" until the development of the main attack had disclosed to the Commander-in-Chief the point at which the impact of this "advanced squadron" would by superior concentration on that point secure that the enemy should there be decisively overpowered. The essence of the matter is that the ships so employed should by virtue of their superior speed be endowed with a tactical mobility sufficient to enable them to discharge the function assigned to them. I need hardly insist on the close analogy which subsists between Nelson's "advanced squadron" and a modern squadron of battle-cruisers similarly employed, and although the conflict of modern warships must needs differ in many essential respects from the conflicts of sailing ships in Nelson's days, yet I think a clear and authoritative exposition of one at least of the uses and functions of the battle-cruiser in a fleet action may still be found in what I have called elsewhere "the last tactical word of the greatest master of sea tactics the world has ever known, the final and flawless disposition of sailing ships marshalled for combat."