Military power, whether afloat or ashore, has in all ages been measured in units of skilled fighting men, properly equipped. Improved equipment increased the value of the unit, as is instanced by the success of the armored Greek, when opposed to the unarmored Asiatic.
Equipment was more or less permanent, could be captured, or passed on to new men; the men were but mortal; and, on the average, lack of men set limits to the power of the state.
From this fact arose the effort to increase, by constant improvement, in the equipment, the effectiveness of the fighting man at the front, and, as civilization developed, and the mechanical arts with it, the value of the unit of power was constantly augmented.
Equipment grew in effectiveness, and also in cost. In the Middle Ages equipment became so expensive that only a small part of the fighting men could be fitted out with the best equipment. Cost is a question of labor used in production, and a certain part of the man-power is required to furnish this labor.
Economy in money requires that we obtain as good equipment as is possible with the money available, for the numbers of fighting men we can count on. It must be here remembered that money means labor, and labor means time. It would be a simple matter to improve the equipment of the fleet, if there were no question of cost. No objection could be found to a complete replacement of the battleship force by new ships of much greater size and power, if there were no loss of time, and no increase in the cost of maintenance. It is not necessary to argue that the men now on the old ships would have much greater fighting power on the new ships. But the millennium has not yet come, and there is the ever present spectre of cost.
When all is said and done, there is available a certain amount of money, to be expended in a given time, for fighting ships. Leaving out of consideration the small craft and auxiliaries, which consume but a small fraction of the total, the available funds will build, in a given time, a number of capital ships, the number depending on the type. What type shall be built? Clearly, the type or types that will give their crews, of a fixed number, the greatest fighting power. And why build capital ships? For the reason that the capital ships do give to a fixed number of men the greatest fighting power. Fighting power means offence and defence. It is just as necessary to protect our own men and material, as it is to damage or destroy the enemy's men and material.
The battleship has been developed into a machine that represents the greatest amount of fighting power that can be obtained from its crew. There is both offence and defence, balanced evenly. At different periods we will see battleships of different sizes, and different degrees of effectiveness, depending on the state of mechanical development at the time. But always there is the balance between offence and defence. A ship is no more a battleship, if she has no armor, than if she has no guns; if she has no torpedo protection than if she has no offence against torpedo vessels. The battleship has consistently represented the maximum fighting power for a given crew, which is the only thing that counts on the day of battle.
Many times have we seen special types evolved, even in capital ships. They have been brought about in most cases, perhaps in all, by ideas that might be traced to other bases than the fundamental one of fighting, and of producing fighting equipment. Already we have seen many of them disappear, after a short life, while the battleship type so far has remained. We need only mention the ram, the commerce destroying cruiser, the armored cruiser, the monitor. They all have wasted money that should have gone into fighting ships. We now have the battle cruiser, that has grown until it is twice as expensive as a battleship of its date. Has it adequate fighting power against capital ships? There is but a limited offence and practically no defence. We shall perhaps see the battle cruiser go the way of the others.
We cannot tell who will be our enemies of the future. It takes a long time to build a fighting fleet, much longer than it takes to start a war. As long as we cannot predict whom we shall have to fight, and what forces we must have, we can only prepare on the basis of our own ultimate strength. We can tell how many skilled fighters we can obtain for the navy, and how many others must be reserved for the army. The number is large, the cost of equipment is large, and we cannot afford to waste any labor in building it—waste it on material that will not give our men an adequate amount of fighting power for the cost represented. That should always be the criterion. Do we get a proper return in fighting power for the expenditure?
What is fighting power in a battleship? First, it is represented by the destruction the ship can accomplish. Secondly, it is the defence it affords, from destruction, to its own crew. We must consider these separately.
The first, the offence, is nowadays easily measured. We no longer expect to lay alongside and board, or to ram, or perhaps even to torpedo, in a capital ship action. The power of offence in a battleship is measured by the number of effective hits she can make with her main battery, before her allowance of ammunition is expended. It is useless to make hits that glance off armor or decks, that make small holes in light upper works, or that do minor damage about the decks. It is only when serious damage is being done that the fighting power of the enemy is being crippled. Also, it is useless to rain projectiles about his ships, without hitting.
Let us now consider the defence. This has perhaps shown up better in the battles of the present war than has the offence. Battleships have been torpedoed in battle, and have remained in line. Ships have been exposed to heavy fire, such as, before the war, would have been considered fatal, and they have been heavily hit, but they went on fighting. But still, some of the ships, after receiving a few hits, were out of control, and some ships barely reached port. There is still much to be desired in the defence. There should be no lucky shots, a ship should withstand severe pounding and still remain a fighting ship; she should be able to receive several torpedoes and not only remain afloat, but an effective fighting ship, with speed and control undiminished, and offensive power intact. Do we say that this is impossible? It is not. It can be done, if we give to protection its proper place. It may be that in Farragut's time the best defence was a vigorous offence, but times have changed; main batteries at short range are now entirely too vigorous for an undefended ship to withstand.
These two, offence and defence, are the main requirements in a capital ship. We have gotten into the habit of expecting a certain fixed amount of them in every battleship, depending on its size; in other words, these two have been given a fairly standard percentage of the total displacement, and it has not been a small one either. Perhaps this has been a bad habit, but there you are, and, after all, a habit is always the result of subconscious justification, if nothing more. We can often justify an action to ourselves, even without logic. If it withstands the test of time, it is usually right.
Providing as large an amount of offence and defence as possible in each ship ensures fighting efficiency and economy of expenditure. These two, offence and defence, should be as large as it is possible to make them, and other factors should be of secondary importance, and receive corresponding attention and weight. Not to do so means that we distrust our premises and neglect what should be considered an axiom, namely, that fighting power consists of but two things, as we have said, offence and defence.
Chief of the secondary factors that go to make up the battleship, leaving out of consideration the hull that carries all, is mobility. A battleship must of course be brought to the scene of action, and within striking distance of the enemy. When she has arrived at the distance she chooses, she must maintain her position so as to fight her battery to the best advantage, and she should be able to take advantage of the changing conditions of the battle. To do all this she must have power of motion and of controlling her motion. We need not here discuss the question of manœuvering ability, since this does not cost much, and is not so important as it was in the days when the ship herself was intended to be the weapon.
Mobility requires a certain maximum speed and also ability to travel a considerable distance, while hunting the enemy. The first requires a certain expenditure, irrespective of the second, and both together, if insisted on in exaggerated amount, mean a very heavy expenditure, to the detriment of fighting power. We should therefore inquire carefully whether they are needed in great amount.
We can perhaps arrive at an answer better by inquiring how much mobility we can afford to give the battleship. It might be said at once that the battleship will not be required to chase small craft, nor fast cruisers, not even the ships of the battle-cruiser type. We recognize readily that this is beyond the capacity of the type. What then is she required to chase? There is no other type except her own type. If it should be required that she chase other battleships, then this can be done only in the case of older ships of the type, for, if the higher speed type is approved and copied by other nations, then the difference of speed that makes overtaking possible disappears, and if the type is not approved, the enemy will have instead a type of greater fighting power, for the same expenditure, and it would not be safe to engage in pursuit of such an enemy. There are therefore limitations in the uses of high speed in a battleship.
The question of how much mobility we can afford to give the battleship type depends on what we lose in fighting power when we substitute extreme mobility. There was a time when we were satisfied with fifteen knots in a battleship, as a maximum speed, but we will find that the weight or cost given to the motive power at the time was about the same as we would now give to a modern ship with a higher speed. In other words, maximum speed grows with time, just as size and other qualities do. It is therefore not an absolute figure, but a relative one. It is when we attempt to determine what we gain or lose in fighting power by decreasing or increasing the motive power, that we can arrive at a fairly satisfactory determination of what cost we can afford to stand for motive power.
It has been customary in our usual standard battleship to give about 40 per cent of the displacement to fighting power, represented by armament, armor, and ammunition, and 15 per cent to motive power, the hull making up the remainder. The hull always includes a considerable amount of weight that is strictly protection, such as the armored decks, and torpedo protection, so that the percentage given to fighting power is really considerably greater than the figures show. If now we take away some of the displacement used for motive power, what can we do with it? Evidently not much, since we could not take very much after all. The ship must have some motive power, and common sense will indicate without any figures at all that we could certainly not take away more than, say, half. Seven per cent of the total added to the forty or more already given to fighting power would not make any startling changes in the power of the battery, the thickness of the armor, or the amount of ammunition, especially as we would want to increase all of these factors at the same time. The loss in motive power represented by the seven per cent would reduce the radius of action to half, and the maximum speed from 21 to somewhere around 16 knots. It does not need any elaborate argument to show that the fighting power does not lose much if we retain the present speed and radius of action, and that there is therefore nothing to be gained by reducing these. The question now becomes, What do we lose when we attempt to increase radically the cost of motive power?
It might here be mentioned, though it should not be necessary, that minor changes from one design to the next, in the quantities referred to, are of no importance, provided they are not progressive. There is no absolute limit in either of the conflicting factors, and one or two per cent one way or the other need not be considered.
We must not, furthermore, take into account large quantities of fuel taken on board for a long voyage, which greatly increase the draft. It is never intended that these should be on board at the time of action, and it is only the weight on board in fighting trim that need be considered. We are not now concerned with any ill effects such extra weights might have on the habitability or seaworthiness of the vessel.
If, now, we should double the allowance given to motive power, we see that the effect on fighting power, if we retain the same total cost, is as great as the effect on the motive power was in the previous instance. The allowance is cut from 40 per cent to 25 per cent, and the effect on each of the quantities included in the general term, fighting power, is serious. We would have.left only about 60 per cent of the previous quantities; thus, the armor would have to be reduced from thirteen to eight inches in thickness, the battery from twelve guns to eight, and the other factors in proportion. Clearly, the effect is not a happy one from the point of view of fighting power. To offset this, we have only increased the maximum speed from 21 to 23 knots, and added a little to the radius of action, hardly a compensating advantage.
In our latest battleships we 'have increased the speed from 21 to 23 knots. If we had retained the size previously standard, the above would have represented the result. It has been necessary to increase the size and cost of the vessel to obtain this increased speed. Of course there were other increases made, principally in the battery power, but we paid for the increased speed just the same. The size of the vessel was increased over thirty per cent, or by an amount equivalent to nearly the whole of the fighting power of the previous smaller vessel. That the number of guns in the main battery was increased fifty per cent does not imply that the fighting power has been correspondingly increased. The size of the target has been increased, or in other words the ability, and therefore the certainty, of the enemy to increase the number of his effective hits; the efficiency of the three-gun turrets is probably less at medium ranges, from the ballistic standpoint; and we might question whether after all the fighting power has been much increased.
It is to be expected that the size of battleships will increase and continue to increase, and we might expect with each increase of size a small increase of speed, and perhaps of normal radius, but it is natural to assume that the country will expect also a corresponding increase in the fighting power of the larger craft. There is no future limit to the size of the type, nor to the ultimate speed that will be attained, but the country must pay for the total navy finally built, and has a right to expect proper fighting efficiency.
If the above has been the effect of doubling the cost of the motive power, what shall we say of the latest proposition, the so-called fast battleship? Here we have motive power comparable to that of our proposed battle-cruisers, and fighting power distinctly inferior to that of the last class of battleships, the 21-knot ships. The displacement is nearly doubled, and the cost, if the vessel is ever built, will be more than doubled. The result must necessarily be that in the long run, in a given term of years, the fighting power of the entire fleet must suffer. And what would we gain by it? Merely that these vessels, in some circumstances, might run at a higher speed than the rest of the fleet. The offensive power is not greater than that of contemporaries of slower speed, it is measured by the allowance of ammunition, and the use that is made of it. Would this vessel, if she dashes here and there at high speed, making a few hits here and a few there, do a greater sum total of damage than if she settled down to fight an opponent in the old-fashioned way? After all, we are not concerned with an indecisive battle, where there is a little damage done, and a ship sunk here and there. We must consider a battle that will settle, once for all, for that war, the mastery of the seas. For the money that we spend on these vessels, the enemy can put more than twice the fighting power afloat, and where then is our mastery of the seas?
Neither can we consider the possibility of shaking the enemy's morale, by concentrating fast ships on detached portions of his line and destroying them. In the first place, we must expect to meet an enemy as determined as ourselves, and not to be shaken by small losses. In the second place, we can expect him to be equally skillful, and not to leave a few units unsupported. Again, concentration can be of value only at short range, for at long range small differences of distance disappear, and concentration of fire on one ship means that other ships will not get the proper amount of attention. Can we imagine these vessels, lightly armored, and immense target, coming to close quarters with standard battleships?
In all this discussion, we deal with equal forces on both sides. If we were greatly superior to our opponent, the exact type of ship would be unimportant. If we were much inferior, we would have no chance anyway. The assumption of equal forces appears reasonable. Even if we were slightly superior, we could not give hostages to fortune by wasting fighting power.
If the high speed battleship does not seem a reasonable proposition in a general battle, then why the high speed? As we have said before, we would not expect a battleship to chase small craft. We do not use a sledge hammer to smash a fly. It is too slow, and takes too much effort. We get a swatter, a light, quick, cheap weapon. If the small craft are going to bother us, we can make plenty of swatters, of the requisite kind, out of the fifty millions one of these fast battleships will cost.
It might be said that we need high speed to overhaul the enemy and bring him to action. But we do not build these ships over night. It is a long, painful process, and meanwhile our prospective enemy can build the same kind. Can we ever steal a march on our possible enemies, and build vessels that cannot be copied in sufficient numbers before ours are ready? That has not, with us, been the case in the past, and it will not be in the future. It has not been so with others, except where they had a great building capacity, which means, of course, great available man power.
Again, if we have the superior fighting fleet, but inferior speed, it might be said that the enemy can harry our coasts, and do much damage, before he is brought to action. That has been said many times, and as often it has been answered that such action has no military value, and will not decide the war. There never yet was a case of an inferior, though faster, fleet avoiding contact with the superior fleet. In the end there was either battle or blockade, and one is as effective as the other.
Exceptionally high speed in a battleship, then, seems to be a thing to avoid, and a moderate speed, which will not detract from fighting power, is the correct answer. We might examine, now, the case of a possible exaggeration of the other factor in mobility, namely, radius of action.
To be sure, we have so far not had cause to fear a loss of fighting power on account of an exaggeration of radius of action. In the past, it has usually been the coal pile which has been robbed, when an extra inch of armor was wanted, or an extra knot of speed, or some other showy thing. It might even have been said that we had not had enough radius of action. The radius that appears in the description of a battleship is the radius she has from the time she joins battle, at least that is the intent. It is the radius at normal displacement, which is supposed to be the fighting displacement.
Viewed from this point, it must be admitted that our fuel supply in normal condition has been large enough, and needs no increase. If a vessel gets into action with a normal supply, she will have enough to carry her through the action, and after that, who cares? If we win, we can take care of our ships, and if we lose—what does it matter? We would lose the ships too. Remember, we are speaking of a fight to the finish.
The same reasoning as before holds here too. A little more or a little less normal fuel does not affect fighting power seriously. It might even be said that, since our present normal supply is of the order of five per cent of the displacement, there is no danger of loss of fighting power, no matter what is done, so long as excessive increase is not contemplated.
Until the battle becomes imminent, there are various ways of maintaining the battleships, but they do not affect fighting power. We have contemplated fueling at sea, and we have prepared to carry emergency fuel. Either can fulfill the object, and neither affects fighting power.
Having fixed on the policy that in the battleship a definite, large percentage, as large as possible, of the displacement, should be given to fighting power, and no reduction, for secondary purposes, tolerated, we might at some length discuss the proper division of the displacement, or cost, among the elements of fighting power.
Before undertaking this it will be well again to state that there is no limit to the future development in size, nor in speed, nor in any other quality, but these qualities should retain their proper relative magnitudes. There is bound to be increased size. It is just natural development of the species. We now believe that the Panama Canal is a final limit. It is not, nor will any other present or future hindrance be. When we come to the point where the canal is too small for the ships we want to build, we will ignore the canal, or we will enlarge it. Development is as sure as fate. And with development of size goes development of speed, of gun-power, of armor, of everything. Increased size always means increase of some one factor in the ship, and as long as the different factors remain at about their proper relative values the fighting power increases.
Fighting power includes offence and defence. It might be stretched to include most of the general characteristics of the hull, such as length, beam, metacentric height, etc. The length and metacentric height are the most important of these, from the point of view of fighting.
A battleship should not be longer than necessary, and we should even be prepared to accept some reduction in the efficiency of propulsion, to get a shorter ship. Great length means heavy hull, extra armor and decks, greater target, higher center of gravity, and wetter decks in a head sea. It also requires more weight for torpedo protection. The present tendency, due to the canal limitations, is to increase displacement by increasing length. This has the effect of reducing fighting efficiency.
Metacentric height has an important effect on the efficiency of the ship. There should be enough to prevent great heel when firing a salvo, or turning at speed, but not so much as unduly to cut down the period of rolling. A short rolling period always means much rolling. If a period of about twenty seconds for a complete roll could be obtained, rolling would be almost eliminated, except in the severest weather. Metacentric height is also a factor in the range of stability.
Coming now to the factors more directly concerned in fighting, we will start with torpedo protection. A battleship should be so protected that she can stand a torpedo explosion in any part of the hull without disablement. There is no present difficulty, with our present type, in nearly accomplishing this, and the ship will stand torpedoing several times, in different locations, without great loss of fighting efficiency. The only important parts that cannot now be protected are the rudder, propellers, and shafting, and a hit in their vicinity may mean loss of motive power. It might be possible to improve this situation by a different design of hull, but probably with a loss of propelling efficiency, and whether it is worth while is open to question. There is no doubt, however, that torpedo protection should be thoroughly carried out, and large size is for this object a distinct advantage.
Considering now the armor protection, we can establish it at once as a fact that if the vessel is intended to fight only at long range, as seems to be a favorite idea, there is no need for the side armor, since it becomes a vanishingly small part of the target. This is, however, far from the actual fact. The vessel may have to do some fighting at long range, but how much of her scanty allowance of ammunition can she afford to throw away at long range? Remember that when her ammunition is gone her fighting power disappears.
History shows that never yet has a decisive action been fought between nearly equal forces at long range, and the term is here used in a relative sense, each period having its own definition of long range. The reason for fighting a decisive battle at close range is not hard to find. The offence is a matter of how many effective hits can be made. Therefore we may expect the same thing to come to pass. Why should we attempt to decide a battle at long range? Cannot much greater damage be done at short range? Of course we will suffer ourselves, but we cannot expect to fight without receiving damage. A successful fighter always takes punishment, and is able to withstand it better than his opponent. That is the whole thing in a nutshell.
The battleship must therefore be designed primarily to fight at short range, and secondarily at long range. High spotting stations, kite balloons, elaborate fire control instruments, are all good in their way, and probably useful, and should be developed. The ship may need them at long range. But these things will all be swept away when we come to the really serious part of the fighting. Then we will want thick armor, powerful guns, simple and rugged turret machinery, and plenty of ammunition.
Our ships are not now armored in such a way that they can stand up for a long time at short range. They may do very well at 12,000 yards, but that is not short range. The range can be considered short when say more than fifty per cent of hits can be made, by the average ship. It will also be necessary to be somewhat independent of range-finders and range keeping. These things we cannot expect to survive in a decisive battle. Perhaps we might, for the present, define short range as 5000 yards. If, at this distance, our ships were fighting broadside to broadside, or, as they used to say, yardarm to yardarm, the fifty per cent of hits would probably all be effective, and the damage would be great. We should fit armor that will prevent this.
Inclined armor will go a long way to accomplish this. This is not a new idea. It was used in the Merrimac of the sixties. It is used now in our turret fronts. We can incline all our side armor inward at say 45 degrees, and it would be proof at very short range against the heaviest modern projectile, if of the thicknesses now used. It is a delicate problem in stability for the naval architect, but it can be done.
Our barbettes will need greater thickness than they have at present, and should be made considerably heavier. It might be possible to compensate somewhat for this by reducing their heights. This will be touched on later.
Protective decks, of the thickness we now use, are good enough at short range, but as the ship must be exposed to gun fire at long range, provision should be made for it. There is no way of escaping serious damage at long range, if the enemy obtains hits. If the protective deck were made narrower, as a result of inclining the side armor inward, we could afford to make it thicker, but not otherwise. The decks now are so heavy, and their effect on stability so marked, that we could hardly afford to put any more weight into them. The protective plating on our decks now amounts to about 10 per cent of the displacement.
The secondary battery is intended only for protection against torpedo craft. Yet we see a great number of men on our battleships that are used only to man these small guns. The number is quite comparable to that used for the main battery. This does not seem logical. If so many fighting men are really necessary for an object that is quite secondary, the natural inference is that the existence of the type is rather precarious. There is need for depending more on passive torpedo protection, just as against gun fire we depend more on passive armor protection, and less on "a well-directed fire from our own guns." That this is quite logical is indicated by the fact that in our latest ships the torpedo protection is quite as efficient against torpedoes as the armor is against heavy projectiles. A weapon of destruction is intended for the offensive, and not primarily for the defensive. There is of course no objection to smashing a destroyer if we get a chance, though, as has been said before, it is cheaper to have smaller types to look out for that. The secondary battery and its crews should be much reduced.
It is hardly necessary to mention torpedo outfits. It is coming more and more to be recognized that these have no place on a battleship, and the outfits we now fit are considerably reduced from what we at one time fitted. It is to be hoped that at a date not very distant they will be entirely eliminated.
Now, last of all, we come to a consideration of the main battery, the primary weapon of the battleship. There has been so much argument about this matter as to leave us entirely confused; there have been so many different arrangements, numbers, and types, that it is quite certain no logic has governed.
The British have come to the belief that not more than eight heavy guns should be mounted on one ship, but they have been building moderate sized ships, and for a special field of action. It is doubtful whether we could take their example for our own guidance, especially when we build larger ships.
We all have a feeling, which is founded on subconscious conviction, as we have not yet been able to justify it by logic, that a larger ship should have a greater battery; in fact, that we are not warranted in building a larger ship unless we increase the battery in proportion. We can easily justify this idea on the basis of economy. There should certainly be at least a standard percentage, for the offensive, in every ton of displacement, and progress in development would seem to call for an ever increasing percentage. Should not every successive phase in development increase the fighting power of the men on board? Hence the distrust with which we regard a design which doubles the displacement, for purposes of speed, and leaves the battery without such increase.
We may therefore feel justified if, on our larger displacements, we carry a heavier battery than the British have placed on their standard battleships. The difficulty is, however, in making proper use of the larger weight. Shall we use larger caliber guns, or more guns, or longer and more powerful guns?
We have mounted up to six turrets on one ship, and have lost some of our fear of interference between the different turrets. A large number of turrets requires, however, a heavy weight of armor for the individual barbettes, and more is used up in the turrets than if we used fewer turrets with a greater number of guns per turret. The need for a greater amount of armor protection on our ships, so as to enable them to fight at closer range, may force our hand in this respect, and compel the adoption or retention of multiple gun turrets, much as we might prefer not to do so, for reasons of putting all our eggs in one basket. This latter point becomes more serious at short range, and will require more careful consideration.
There would be a certain amount of armor weight available for turrets and barbettes. If we used this weight for two-gun turrets, we would have thinner armor than if we used it for three gun turrets, and the difference would be greater still for four-gun turrets. It might be said that the turret fronts are now impenetrable, and need no further weight, even if larger guns were used. That is not the case with the barbettes, and it is these that consume so much weight. The fewer the gun stations, the less the weight of the barbettes for a given thickness.
In a two-gun turret, we expose two guns and their crews to destruction from one penetrating projectile. It has been said that with a three-gun turret we expose three guns instead of two. That is true, as far as it goes, but in this case we can have a thicker port plate, and thicker barbette plating, and so prevent penetration. In the case of a four-gun turret, this advantage is even more pronounced, and in addition we can still further protect the turret by fitting a thick plate between the two pairs of guns, an arrangement that is feasible in this case, but not in the three-gun arrangement.
As far as the strength of the hull is concerned, we need have no fear, on account of a four-gun battery, since the stresses will not be greater than with the two-gun arrangement, if each four-gun turret takes the place of two adjacent two-gun turrets.
It seems therefore to be sound judgment not to go back to the two-gun arrangement, and, further, to go to the four-gun turret as soon as practicable. It would, however, be wise to enlarge the turrets to give the individual guns more room, and to prevent jamming of adjacent guns by a single hit. This would also somewhat reduce the interference between adjacent guns, and improve the ballistics at medium ranges. This can be done, and the power of resistance of the barbette greatly increased, by making it conical, the top diameter being the greater, and the inclination of the elements about 15 degrees.
As regards height of battery above water, we have adopted definite heights for Numbers I and IV turrets. From the point of view of weather and sea, there is no reason why we should use greater heights for the other two turrets in our later ships. This present arrangement, the vertical echelon, has been dictated by two considerations; one is the more compact arrangement, permitting placing the whole battery in a shorter length, the other is the desire. for end-on fire. If we retain four turrets, in a larger ship, there should be no difficulty as regards the first consideration. As regards the other, is end-on fire really so important? We pay for it heavily in this case; it has been costing us over 500 tons, in heavier barbettes and foundations.
It is no doubt a time-honored arrangement, to get as much end-on fire as possible, and conservatism would dictate retaining it. It arose in the days when fighting at very short ranges was contemplated, when three thousand yards constituted long battle range, when ramming was still finding advocates. This was also the day of the powerful turret turning gear, which permitted swinging very swiftly from side to side, to keep on the target in spite of the quick turn in manœuvering to ram, or to strike an enemy alternately starboard and port. It hardly accords with our present-day ideas of fire control and fighting. There is no doubt that most, if not all, of the fire in action will be on the broadside, and that the vertical echelon arrangement is unnecessary.
The indications are then that we should employ an arrangement of multiple gun turrets, as far as possible on the same level, the forward turrets perhaps being higher than the after turrets. This arrangement will incidentally be quite a help in getting satisfactory stability, as it will not raise the center of gravity so much.
When we have reached the limit of four four-gun turrets, the question again presents itself, how to take care of a still further increase in the main battery. We have now adopted the 16-inch gun. Shall we go to still larger calibers? Undoubtedly we shall. An additional four-gun turret would require a much greater increase in length, which is very undesirable. We would hardly be prepared to put five or six guns in one turret. We can then obtain the increase in battery power only by increasing the caliber, or by increasing the length of the guns, and the latter method has much closer limitations than the former.
Here it would be well to observe that from many points of view it would be better to increase the length and the initial velocity of the guns, rather than to increase the caliber. Thus, penetration of armor is obtained more easily with a small than with a large diameter of projectile, of the same striking energy. A little manipulation of the penetration formula shows that the thickness penetrated is proportional to the ? power of the striking energy divided by the caliber. Therefore, the larger the caliber, for a given energy, the less the penetration. There is then as much penetration to be obtained with the 14-inch projectile as with the 16-inch, if the striking velocities are in the proportion of 3200 to 2600. Again, the greater velocity will give the required ranges with a flatter trajectory, and thus, at comparatively short ranges, will increase the chance of hitting.
A little consideration will show, however, that although this is all true theoretically, the differences from the customary practice must be rather extreme, in order to obtain reasonable increases in the qualities named. It would not be enough advantage to make it worth while, if the velocity were increased from 2600 to 2800. The difference in the angle of fall would be too slight to make much difference, and the difference in penetration also would hardly compensate for the cost. If, now, we could get a velocity of 3500 to 4000, the effect would be well worth while. This must, however, wait further developments, as we do not want guns that would have an accuracy life of only about fifty rounds. It therefore seems that the larger calibers must come, since that is the only feasible way to increase battery power.
In conclusion, it must again be emphasized that we want fighting power above everything else on our battleships. We want our ton of fighting power for every two tons of displacement. The crews that will fight our battleships in the great deciding battles of the future will need to strike hard, and they will need to survive effective until the work is done. Fighting power is composed of but two things, offence and defence.