I have already given my first impressions of Their Majesties the King and Queen, and time only confirmed them. Neither ever missed an opportunity to show their appreciation of the part that we were playing.

The zeal with which the King entered into the celebration of our Fourth of July made him very popular with all our men. He even cultivated a taste for our national game. Certain of our early contingents of soldiers encamped near Windsor; here they immediately laid out a baseball diamond and daily engaged in their favourite sport. The Royal Family used to watch our men at their play, became interested in the game, and soon learned to follow it. The Duke of Connaught and the Princess Patricia, his daughter, had learned baseball through their several years' residence in Canada, and could watch a match with all the understanding and enthusiasm of an American "fan." As our sailors and soldiers arrived in greater numbers, the interest and friendliness of the Royal Family increased. One of the King's most delightful traits is his sense of humour. The Queen also showed a great fondness for stories, and I particularly remember her amus.e.m.e.nt at the famous remark of the Australians--perhaps the most ferocious combatants on the Western Front--about the American soldier, "a good fighter, but a little rough."

Of all the anecdotes connected with our men, none delighted King George so much as those concerning our coloured troops. A whole literature of negro yarns spread rapidly over Europe; most of them, I find, have long since reached the United States. The most lasting impression which I retain of the head of the British Empire is that he is very much of a human being. He loved just about the same things as the normal American or Englishman loves--his family, his friends, his country, a good story, a pleasant evening with congenial a.s.sociates. And he had precisely the same earnestness about the war which one found in every properly const.i.tuted Briton or American; the victories of the Allies exhilarated King George just as they exhilarated the man in the street, and their defeats saddened him just as they saddened the humblest citizen. I found in His Majesty that same solemn sense of comradeship with America which I found in the English civilians who saluted the American uniform in the street.

As an evidence of the exceedingly cordial relations existing between the two navies the Admiralty proposed, in the latter part of May, that I should a.s.sume Admiral Bayly's command for several days while he took a little vacation on the west coast of Ireland. Admiral Bayly was the Commander-in-Chief of all the British forces operating on the Irish coast. This command thus included far more than that at Queenstown; it comprised several naval stations and the considerable naval forces in Irish waters. Never before, so I was informed, had a foreign naval officer commanded British naval forces in time of war. So far as exercising any control over sea operations was concerned, this invitation was not particularly important. Matters were running smoothly at the Queenstown station; Admiral Bayly's second in command could easily have kept the machine in working order; it was hardly likely, in the few days that I was to command, that any changes in policy would be initiated. The British Admiralty merely took this way of showing a great courtesy to the American navy, and of emphasizing to the world the excellent relations that existed between the two services. The act was intended to symbolize the fact that the British and the American navies were really one in the thoroughness of their co-operation in subduing the Prussian menace. Incidentally the British probably hoped that the publication of this news in the German press would not be without effect in Germany. On June 18th, therefore, I went to Queenstown, and hoisted my flag on the staff in front of Admiralty House. I had some hesitation in doing this, for American navy regulations stipulate that an Admiral's flag shall be raised only on a ship afloat, but Admiral Bayly was insistent that his flag should come down and that mine should go up, and I decided that this technicality might be waived. The incident aroused great interest in England, but it started many queer rumours in Queenstown. One was that Admiral Bayly and I had quarrelled, the British Admiral, strangely enough, having departed in high dudgeon and left me serenely in control. Another was that I had come to Queenstown, seized the reins out of Admiral Bayly's hands, thrown him out of the country, and taken over the government of Ireland on behalf of the United States, which had now determined to free the island from British oppression!

However, in a few days Admiral Bayly returned and all went on as before.

During the nearly two years which the American naval forces spent in Europe only one element in the population showed them any hostility or even unfriendliness. At the moment when these lines are being written a delegation claiming to represent the "Irish Republic" is touring the United States, asking Americans to extend their sympathy and contribute money toward the realization of their project. I have great admiration for the ma.s.s of the Irish people, and from the best elements of these people the American sailors received only kindness. I have therefore hesitated about telling just how some members of the Sinn Fein Party treated our men. But it seems that now when this same brotherhood is attempting to stir up hatred in this country against our Allies in the war, there is a certain pertinence in informing Americans just what kind of treatment their brave sailors met with at the hands of the Sinn Fein in Ireland.

The people of Queenstown and Cork, as already described, received our men with genuine Irish cordiality. Yet in a few weeks evidence of hostility in certain quarters became apparent. The fact is that the part of Ireland in which the Americans were stationed was a headquarters of the Sinn Fein. The members of this organization were not only openly disloyal; they were openly pro-German. They were not even neutral; they were working day and night for a German victory, for in their misguided minds a German victory signified an Irish Republic. It was no secret that the Sinn Feiners were sending information to Germany and constantly laying plots to interfere with the British and American navies. At first it might be supposed that the large number of sailors--and some officers--of Irish extraction on the American destroyers would tend to make things easier for our men. Quite the contrary proved to be the case. The Sinn Feiners apparently believed that these so-called Irish-Americans would sympathize with their cause; in their wildest moments they even hoped that our naval forces might champion it. But these splendid sailors were Americans before they were anything else; their chief ambition was the defeat of the Hun and they could not understand how any man anywhere could have any other aim in life. They were disgusted at the large numbers of able-bodied men whom they saw in the streets, and did not hesitate to ask some of them why they were not fighting on the Western Front. The behaviour of the American sailors was good; but the mere fact that they did not openly manifest a hatred of Great Britain and a love of Germany infuriated the Sinn Feiners. And the eternal woman question also played its part. Our men had much more money than the native Irish boys, and could entertain the girls more lavishly at the movies and ice-cream stands. The men of our fleet and the Irish girls became excellent friends; the a.s.sociation, from our point of view, was a very wholesome one, for the moral character of the Irish girls of Queenstown and Cork--as, indeed, of Irish girls everywhere--is very high, and their companionship added greatly to the well-being and contentment of our sailors, not a few of whom found wives among these young women. But when the Sinn Fein element saw their sweethearts deserting them for the American boys their hitherto suppressed anger took the form of overt acts.

Occasionally an American sailor would be brought from Cork to Queenstown in a condition that demanded pressing medical attention. When he regained consciousness he would relate how he had suddenly been set upon by half a dozen roughs and beaten into a state of insensibility. Several of our men were severely injured in this way. At other times small groups were stoned by Sinn Fein sympathizers, and there were many hostile demonstrations in moving-picture houses and theatres. Even more frequently attacks were made, not upon the American sailors, but upon the Irish girls who accompanied them. These chivalrous pro-German agitators would rush up and attempt to tear the girls away from our young men; they would pull down their hair, slap them, and even kick them. Naturally American sailors were hardly the type to tolerate behaviour of this kind, and some b.l.o.o.d.y battles took place. This hostility was increased by one very regrettable occurrence in Queenstown. An American sailor was promenading the main thoroughfare with an Irish girl, when an infuriated Sinn Feiner rushed up, began to abuse his former sweetheart in vile language, and attempted to lay hands on her. The American struck this hooligan a terrific blow; he fell backward and struck his head on the curb. The fall fractured the a.s.sailant's skull and in a few hours he was dead. We handed our man over to the civil authorities for trial, and a jury, composed entirely of Irishmen, acquitted him. The action of this jury in itself indicated that there was no sympathy among the decent Irish element, which const.i.tuted the great majority, with this sort of tactics, but naturally it did not improve relations between our men and the Sinn Fein. The importance of another incident which took place at the cathedral has been much exaggerated. It is true that a priest in his Sunday sermon denounced the American sailors as vandals and betrayers of Irish womanhood, but it is also true that the Roman Catholics of that section were themselves the most enraged at this absurd proceeding. A number of Roman Catholic officers who were present left the church in a body; the Catholic Bishop of the Diocese called upon Admiral Bayly and apologized for the insult, and he also punished the offending priest by a.s.signing him to new duties at a considerable distance from the American ships.

But even more serious trouble was brewing, for our officers discovered that the American sailors were making elaborate plans to protect themselves. Had this discovery not been made in time, something like an international incident might have resulted. Much to our regret, therefore, it was found necessary to issue an order that no naval men, British or American, under the rank of Commander, should be permitted to go to Cork. Ultimately we had nearly 8,000 American men at this station; Queenstown itself is a small place of 6,000 or 7,000, so it is apparent that it did not possess the facilities for giving such a large number of men those relaxations which were necessary to their efficiency. We established a club in Queenstown, provided moving pictures and other entertainments, and did the best we could to keep our sailors contented.

The citizens of Cork also keenly regretted our action. The great majority had formed a real fondness for our boys; and they regarded it as a great humiliation that the rowdy element had made it necessary to keep our men out of their city. Many letters were printed in the Cork newspapers apologizing to the Americans and calling upon the people to take action that would justify us in rescinding our order. The loss to Cork tradesmen was great; our men received not far from $200,000 to $300,000 a month in pay; they were free spenders, and their presence in the neighbourhood for nearly two years would have meant a fortune to many of the local merchants. Yet we were obliged to refuse to accede to the numerous requests that the American sailors be permitted to visit this city.

A committee of distinguished citizens of Cork, led by the Lord Mayor, came to Admiralty House to plead for the rescinding of this order.

Admiral Bayly cross-examined them very sharply. It appeared that the men who had committed these offences against American sailors had never been punished.

Unless written guarantees were furnished that there would be no hostile demonstrations against British or Americans, Admiral Bayly refused to withdraw the ban, and I fully concurred in this decision. Unfortunately the committee could give no such guarantee. We knew very well that the first appearance of Americans in Cork would be the signal for a renewal of hostilities, and the temper of our sailors was such that the most deplorable consequences might have resulted. We even discovered that the blacksmiths on the U.S.S. _Melville_ were surrept.i.tiously manufacturing weapons which our men could conceal on their persons and with which they proposed to sally forth and do battle with the Sinn Fein! So for the whole period of our stay in Queenstown our sailors were compelled to keep away from the dangerous city. But the situation was not without its humorous aspects. Thus the pretty girls of Cork, finding that the Americans could not come to them, decided to come to the Americans; every afternoon a trainload would arrive at the Queenstown station, where our sailors would greet them, give them a splendid time, and then, in the evening, escort them to the station and send a happy crowd on their way home.

But the Sinn Feiners interfered with us in much more serious ways than this. They were doing everything in their power to help Germany. With their a.s.sistance German agents and German spies were landed in Ireland.

At one time the situation became so dangerous that I had to take experienced officers whose services could ill be spared from our destroyers and a.s.sign them to our outlying air stations in Ireland.

This, of course, proportionately weakened our fleet and did its part in prolonging the war.

CHAPTER III

THE ADOPTION OF THE CONVOY

I

All this time that we were seeking a solution for the submarine problem we really had that solution in our hands. The seas presented two impressive spectacles in those terrible months of April, May, and June, 1917. One was the comparative ease with which the German submarines were sinking merchant vessels; the other was their failure materially to weaken the Allied fleets. If we wish a counter-picture to that presented by the Irish Sea and the English Channel, where merchant shipping was constantly going down, we should look to the North Sea, where the British Grand Fleet, absolutely intact, was defiantly riding the waves.

The uninformed public explained this apparent security in a way of its own; it believed that the British dreadnoughts were anch.o.r.ed behind booms, nets, and mine-fields, through which the submarines could not penetrate. Yet the fact of the matter was that the Grand Fleet was frequently cruising in the open sea, in the waters which were known to be the most infested with submarines. The German submarines had been attempting to destroy this fleet for two and a half years. It had been their plan to weaken this great battle force by "attrition"; to sink the great battleships one by one, and in this way to reduce the fighting power of the fleet to such a point that the German dreadnoughts could have some chances of success. Such had been the German programme, widely heralded at the beginning of the war; nearly three years had now pa.s.sed, but how had this pretentious scheme succeeded? The fact was that the submarines had not destroyed a single dreadnought. It was certainly a profitable study in contrasts--that of merchant ships constantly being torpedoed and that of battleships constantly repelling such attacks.

Certainly a careful study of this situation ought to bring out facts which would a.s.sist the Allies in solving the most baffling problem of the war.

Yet there was no mystery about the immunity which these great fighting vessels were enjoying; the submarine problem, so far as it affected the battle fleet, had already been solved. The explanation was found in the simple circ.u.mstance that, whenever the dreadnoughts went to sea, they were preceded by a screen of cruisers and destroyers. It almost seemed as though these surface craft were serving as a kind of impenetrable wall against which the German U-boats were beating themselves in vain.

Yet to the casual observer there seemed to be no reason why the submarines should stand in any particular terror of the destroyers.

Externally they looked like the least impressive war vessels afloat.

When they sailed ahead of the battle squadrons, the destroyers were ungraceful objects upon the surface of the water; the impression which they conveyed was that of fragility rather than of strength, and the idea that they could ever be the guardians of the mighty battleships which sailed behind them at first seemed almost grotesque. Yet these little vessels really possessed the power of overcoming the submarine.

The war had not progressed far when it became apparent that the U-boat could not operate anywhere near this speedy little surface vessel without running serious risk of destruction.

Until the reports of submarine fighting began to find their way into the papers, however, the destroyer was probably the one type of warship in which the public had the smallest interest. It had become, indeed, a kind of ugly duckling of the Navy. Our Congress had regularly neglected it; year after year our naval experts had recommended that four destroyers be built for every battleship, and annually Congress had appropriated for only one or two. The war had also found Great Britain without a sufficient number of destroyers for the purpose of anti-submarine warfare. The Admiralty had provided enough for screening the Grand Fleet in cruising and in battle, but it had been called upon to divert so many for the protection of troop transportation, supply ships, and commerce generally that the efficiency of the fleet had been greatly undermined. Thus Britain found herself without enough destroyers to meet the submarine campaign; this situation was not due to any lack of foresight, but to a failure to foresee that any civilized nation could ever employ the torpedo in unrestricted warfare against merchant ships and their crews.

The one time that this type of vessel had come prominently into notice was in 1904, when several of them attacked the Russian fleet at Port Arthur, damaging several powerful vessels and practically ending Russian sea power in the Far East. The history of the destroyer, however, goes back much further than 1904. It was created to fulfil a duty not unlike that which it has played so gloriously in the World War. In the late seventies and early eighties a new type of war vessel, the torpedo boat, caused almost as much perturbation as the submarine has caused in recent years. This speedy little fighter was invented to serve as a medium for the discharge of a newly perfected engine of naval warfare, the automobile torpedo. It was its function to creep up to a battleship, preferably under cover of darkness or in thick weather, and let loose this weapon against her unsuspecting hulk. The appearance of the torpedo boat led to the same prediction as that which has been more recently inspired by the submarine; in the eyes of many it simply meant the end of the great surface battleship. But naval architects, looking about for the "answer" to this dangerous craft, designed another type of warship and appropriately called it the "torpedo boat destroyer." This vessel was not only larger and speedier than its appointed antagonist, but it possessed a radius of action and a seaworthiness which enabled it to accompany the battle fleet. Its draft was so light that a torpedo could pa.s.s harmlessly under the keel, and it carried an armament which had sufficient power to end the career of any torpedo boat that came its way. Few types have ever justified their name so successfully as the torpedo boat destroyer. So completely did it eliminate that little vessel as a danger to the fighting ships that practically all navies long since ceased to build torpedo boats. Yet the destroyer promptly succeeded to the chief function of the discarded vessel, that of attacking capital ships with torpedoes; and, in addition to this, it a.s.sumed the duty of protecting battleships from similar attack by enemy vessels of the same type.

It surprises many people to learn that the destroyer is not a little boat but a warship of considerable size. This vessel to-day impresses most people as small only because all ships, those which are used for commerce and those which are used for war, have increased so greatly in displacement. The latest specimens of the destroyer carry four-or five-inch guns and twelve torpedo tubes, each of which launches a torpedo that weighs more than a ton, and runs as straight as an arrow for more than six miles. The _Santa Maria_, the largest vessel of the squadron with which Columbus made his first voyage to America, had a displacement of about five hundred tons, and thus was about half as large as a destroyer; and even at the beginning of the clipper ship era few vessels were much larger.

Previous to 1914 it was generally believed that torpedo attacks would play a large part in any great naval engagement, and this was the reason why all naval advisers insisted that a large number of these vessels should be constructed as essential units of the fleet. Yet the war had not made much progress when it became apparent that this versatile craft had another great part to play, and that it would once more justify its name in really heroic fashion. Just as it had proved its worth in driving the surface torpedo boat from the seas, so now it developed into a very dangerous foe to the torpedo boat that sailed beneath the waves.

Events soon demonstrated that, in all open engagements between submarine and destroyer, the submarine stood very little chance. The reason for this was simply that the submarine had no weapon with which it could successfully resist the attack of the destroyer, whereas the destroyer had several with which it could attack the submarine. The submarine had three or four torpedo tubes, and only one or two guns, and with neither could it afford to risk attacking the more powerfully armed destroyer.

The U-boat was of such a fragile nature that it could never afford to engage in a combat in which it stood much chance of getting hit. A destroyer could stand a comparatively severe pounding and still remain fairly intact, but a single sh.e.l.l, striking a submarine, was a very serious matter; even though the vessel did not sink as a result, it was almost inevitable that certain parts of its machinery would be so injured that it would have difficulty in getting into port. It therefore became necessary for the submarine always to play safe, to fight only under conditions in which it had the enemy at such a disadvantage that it ran little risk itself; and this was the reason why it preferred to attack merchant and pa.s.senger ships rather than vessels, such as the destroyer, that could energetically defend themselves.

The comparatively light draft of the destroyer, which is about nine or ten feet, pretty effectually protects it from the submarine's torpedo, for this torpedo, to function with its greatest efficiency, must take a course about fifteen feet under water; if it runs nearer the surface than this, it comes under the influence of the waves, and does not make a straight course. More important still, the speed of the destroyer, the ease with which it turns, circles, and zigzags, makes it all but impossible for a torpedo to be aimed with much chance of hitting her.

Moreover, the discharge of this missile is a far more complicated undertaking than is generally supposed. The submarine commander cannot take position anywhere and discharge his weapon more or less wildly, running his chances of hitting; he must get his boat in place, calculate range, course, and speed, and take careful aim. Clearly it is difficult for him to do this successfully if his intended victim is scurrying along at the rate of thirty or forty miles an hour. Moreover, the destroyer is constantly changing its course, making great circles and indulging in other disconcerting movements. So well did the Germans understand the difficulty of torpedoing a destroyer that they practically never attempted so unprofitable and so hazardous an enterprise.

Torpedoes are complicated and expensive mechanisms; each one costs about $8,000 and the average U-boat carried only from eight to twelve; it was therefore necessary to husband these precious weapons, to use them only when the chances most favoured success; the U-boat commander who wasted them in attempts to sink destroyers would probably have been court-martialled.

But while the submarine had practically no means of successfully fighting the destroyer, the destroyer had several ways of putting an end to the submarine. The advantage which really made the destroyer so dangerous, as already intimated, was its excessive speed. On the surface the U-boat made little more than fifteen miles an hour, and under the surface it made little more than seven or eight. If the destroyer once discovered its presence, therefore, it could reach its prey in an incredibly short time. It could attack with its guns, and, if conditions were favourable, it could ram; and this was no trifling accident, for a destroyer going at thirty or forty miles could cut a submarine nearly in two with its strong, razor-like bow. In the early days of the war these were the main methods upon which it relied to attack, but by the time that I had reached London, another and much more frightful weapon had been devised. This was the depth charge, a large can containing about three hundred pounds of TNT, which, if it exploded anywhere within one hundred feet of the submarine, would either destroy it entirely or so injure it that the victim usually had to come to the surface and surrender.

I once asked Admiral Jellicoe who was the real inventor of this annihilating missile.

"No man in particular," he said. "It came into existence almost spontaneously, in response to a pressing need. Gunfire can destroy submarines when they are on the surface, but you know it can accomplish nothing against them when they are submerged. This fact made it extremely difficult to sink them in the early days of the war. One day, when the Grand Fleet was cruising in the North Sea, a submarine fired a torpedo at one of the cruisers. The cruiser saw the periscope and the wake of the torpedo, and had little difficulty in so manoeuvring as to avoid being struck. She then went full speed to the spot from which the submarine had fired its torpedo, in the hope of ramming it. But by the time she arrived the submarine had submerged so deeply that the cruiser pa.s.sed over her without doing her any harm. Yet the officers and crew could see the submerged hull; there the enemy lay in full view of her pursuers, yet perfectly safe! The officers reported this incident to me in the presence of Admiral Madden, second in command.

"'Wouldn't it have been fine,' said Madden, 'if they had had on board a mine so designed that, when dropped overboard, it would have exploded when it reached the depth at which the submarine was lying?'"

"That remark," continued Admiral Jellicoe, "gave us the germinal idea of the depth charge. I asked the Admiralty to get to work and produce a 'mine' that would act in the way that Admiral Madden had suggested. It proved to be very simple to construct--an ordinary steel cylinder filled with TNT; this was fitted with a simple firing appliance which was set off by the pressure of the water, and could be so adjusted that it would explode the charge at any depth desired. This apparatus was so simple and so necessary that we at once began to manufacture it."

The depth charge looked like the innocent domestic ash can, and that was the name by which it soon came to be popularly known. Each destroyer eventually carried twenty or thirty of these destructive weapons at the stern; a mere pull on a lever would make one drop into the water. Many destroyers also carried strange-looking howitzers, which were made in the shape of a Y, and from which one ash can could be hurled fifty yards or more from each side of the vessel. The explosion, when it took place within the one hundred feet which I have mentioned as usually fatal to the submarine, would drive the plates inward and sometimes make a leak so large that the vessel would sink almost instantaneously. At a somewhat greater distance it frequently produced a leak of such serious proportions that the submarine would be forced to blow her ballast tanks, come to the surface, and surrender. Even when the depth charge exploded considerably more than a hundred feet away, the result might be equally disastrous, for the concussion might distort the hull and damage the horizontal rudders, making it impossible to steer, or it might so injure the essential machinery that the submarine would be rendered helpless. Sometimes the lights went out, leaving the crew groping in blackness; necessary parts were shaken from their fastenings; and in such a case the commander had his choice of two alternatives, one to be crushed by the pressure of the water, and the other to come up and be captured or sunk by his surface foe. It is no reflection upon the courage of the submarine commanders to say that in this embarra.s.sing situation they usually preferred to throw themselves upon the mercy of the enemy rather than to be smashed or to die a lingering and agonizing death under the water. Even when the explosion took place at a distance so great that the submarine was not seriously damaged, the experience was a highly disconcerting one for the crew. If a dozen depth charges were dropped, one after the other, the effect upon the men in the hunted vessel was particularly demoralizing. In the course of the war several of our own submarines were depth-charged by our own destroyers, and from our crews we obtained graphic descriptions of the sensations which resulted. It was found that men who had pa.s.sed through such an ordeal were practically useless for several days, and that sometimes they were rendered permanently unfit for service. The state of nerves which followed such an experience was not unlike that new war psychosis known as sh.e.l.l-shock. One of our officers who had had such an adventure told me that the explosion of a single depth charge under the water might be compared to the concussion produced by the simultaneous firing of all the fourteen-inch guns of a battleship. One can only imagine what the concussion must have been when produced by ten or twenty depth charges in succession. Whether or not the submarine was destroyed or seriously injured, a depth-charged crew became extremely cautious in the future about getting anywhere in the neighbourhood of a destroyer; and among the several influences which ultimately disorganized the _moral_ of the German U-boat service these contacts with depth charges were doubtless the most important. The hardiest under-water sailor did not care to go through such frightful moments a second time.

This statement makes it appear as though the depth charge had settled the fate of the submarine. Yet that was far from being the case, for against the ash can, with its 300 pounds of TNT, the submarine possessed one quality which gave it great defensive power. That was ability to make itself unseen. Strangely enough, the average layman is inclined to overlook this fairly apparent fact, and that is the reason why, even at the risk of repeating myself, I frequently refer to it. Indeed, the only respect in which the subsurface boat differs essentially from all other war vessels is in this power of becoming invisible. Whenever it descries danger from afar, the submarine can disappear under the water in anywhere from twenty seconds to a minute. And its great advantage is that it can detect its enemy long before that enemy can detect the submarine. A U-boat, sailing awash, or sailing with only its conning-tower exposed, can see a destroyer at a distance of about fifteen miles if the weather is clear; but, under similar conditions, the destroyer can see the submarine at a distance of about four miles.

Possessing this great advantage, the submarine can usually decide whether it will meet the enemy or not; if it decides that it is wise to avoid an encounter, all it has to do is to duck, remain submerged until the destroyer has pa.s.sed on, entirely unconscious of its presence, and then to resume its real work, which is not that of fighting warships, but of sinking merchantmen. The chief anxiety of the U-boat commander is thus to avoid contact with its surface foe and its terrible depth charge, whereas the business of the destroyer commander is to get within fighting distance of his quarry.

Ordinarily, conditions favour the U-boat in this game, simply because the ocean is so large a place. But there is one situation in which the destroyer has more than a fighting chance, for the power of the submarine to keep its presence secret lasts only so long as it remains out of action. If it makes no attempt to fight, its presence can hardly ever be detected; but just as soon as it becomes belligerent, it immediately reveals its whereabouts. If it comes to the surface and fires its guns, naturally it advertises to its enemy precisely where it is; but it betrays its location almost as clearly when it discharges a torpedo. Just as soon as the torpedo leaves the submarine, a wake, clearly marking its progress, appears upon the surface of the water.

Though most newspaper readers have heard of this tell-tale track, I have found few who really understand what a conspicuous disturbance it is.

The torpedo is really a little submarine itself; it is propelled by compressed air, the exhaust of which stirs up the water and produces a foamy, soapy wake, which is practically the same as that produced by the propeller of an ocean liner. This trail is four or five feet wide; it is as white and is as distinct as a chalk line drawn upon a blackboard, provided the weather is clear and the sun is in the right direction.

Indeed, it is sometimes so distinct that an easily manoeuvred ship, and even sometimes a merchantman, can avoid the torpedo which it sees advancing merely by putting over the helm and turning out of its course. But the chief value of this wake to the submarine hunters is that it shows the direction in which the submarine was located when the torpedo started on its course. It stands out on the surface of the water like a long, ghostly finger pointing to the spot where the foe let loose its shaft.

As soon as the destroyer sees this betraying disturbance, the commander rings for full speed; and one of the greatest advantages of this type of vessel is that it can attain full speed in an incredibly short time. The destroyer then dashes down the wake until it reaches the end, which indicates the point where the submarine lay when it discharged its missile. At this point the surface vessel drops a depth charge and then begins cutting a circle, say, to the right. Pains are taken to make this circle so wide that it will include the submarine, provided it has gone in that direction. The destroyer then makes another circle to the left.

Every ten or fifteen seconds, while describing these circles, it drops a depth charge; indeed, not infrequently it drops twenty or thirty in a few minutes. If there is another destroyer in the neighbourhood it also follows up the wake and when it reaches the indicated point, it circles in the opposite direction from the first. Sometimes more than two may start for the suspected location and, under certain conditions, the water within a radius of half a mile or more may be seething with exploding depth charges.

It is plain from this description that the proceeding develops into an exceedingly dangerous game for the attacking submarine. It is a simple matter to calculate the chances of escaping which the enemy has under these conditions. That opportunity is clearly measured by the time which elapses from the moment when it discharges its torpedo to the moment when the destroyer has reached the point at which it was discharged.

This interval gives the subsurface boat a certain chance to get away; but its under-water speed is moderate, and so by the time the destroyer reaches the critical spot, the submarine has advanced but a short distance away from it. How far has she gone? In what direction did she go? These are the two questions which the destroyer commander must answer, and the success with which he answers them accurately measures his success in sinking or damaging his enemy, or in giving him a good scare. If he always decided these two points accurately, he would almost always "get" his submarine; the chances of error are very great, however, and that is the reason why the submarine in most cases gets away. All that the surface commander knows is that there is a U-boat somewhere in his neighbourhood, but he does not know its precise location and so he is fighting more or less in the dark. In the great majority of cases the submarine does get away, but now and then the depth charge reaches its goal and ends its career.

If only one destroyer is hunting, the chances of escape strongly favour the under-water craft; if several pounce upon her at once, however, the chances of escaping are much more precarious. If the water is shallow the U-boat can sometimes outwit the pursuer by sinking to the bottom and lying there in silent security until its surface enemy tires of the chase. But in the open sea there is no possibility of concealing itself and so saving itself in this fashion, for if the submarine sinks beyond a certain depth the pressure of the water will crush it.

While the record shows that the U-boat usually succeeded in evading the depth charges, there were enough sunk or seriously damaged or given a bad shake-up to serve as a constant reminder to the crews that they ran great danger in approaching waters which were protected by destroyers.

The U-boat captains, as will appear, avoided such waters regularly; they much preferred to attack their merchant prey in areas where these soul-racking depth charges did not interfere with their operations.

It is now becoming apparent why the great battle fleet, which always sailed behind a protecting screen of such destroyers, was practically immune from torpedo attack. In order to a.s.sail these battleships the submarine was always compelled to do the one thing which, above all others, it was determined to avoid--to get within depth-charge radius of the surface craft. In discharging the torpedo, distance, as already intimated, is the all-important consideration. The U-boat carries a torpedo which has a much shorter range than that of the destroyer; it was seldom effective if fired at more than 2,000 yards, and beyond that distance its chances of hitting became very slight. Indeed, a much shorter distance than that was desirable if the torpedo was to accomplish its most destructive purpose. So valuable were these missiles and so necessary was it that every one should be used to good advantage, that the U-boat's captain had instructions to shoot at no greater distance than 300 yards, unless the conditions were particularly favourable. In the early days, the torpedoes which were fired at a greater distance would often hit the ships on the bow or the stern, and do comparatively little damage; such vessels could be brought in, repaired in a short time, and again put to sea. The German Admiralty discovered that in firing from a comparatively long distance it was wasting its torpedoes; it therefore ordered its men to get so near the prey that it could strike the vessel in a vital spot, preferably in the engine-room; and to do this it was necessary to creep up within 300 yards. But to get as close as that to the destroyers which screened the battleships meant almost certain destruction. Thus the one method of attack which was left to the U-boat was to dive under the destroyer screen and come up in the midst of the battle fleet itself. A few minutes after its presence should become known, however, a large number of destroyers would be dropping depth charges in its neighbourhood, and its chances of escaping destruction would be almost nil, to say nothing of its chances of destroying ships.

The Germans learned the futility of this kind of an operation early in the war, and the man who taught them this lesson was Commander Weddingen, the same officer who had first demonstrated the value of the submarine in practical warfare. It was Otto Weddingen who, in September, 1914, sank the old British cruisers, the _Hogue_, the _Cressy_, and the _Aboukir_, an exploit which made him one of the great popular heroes of Germany. A few months afterward Commander Weddingen decided to try an experiment which was considerably more hazardous than that of sinking three unescorted cruisers; he aspired to nothing less ambitious than an attack upon the Grand Fleet itself. On March 18th a part of this fleet was cruising off Cromarty, Scotland; here Weddingen came with the _U-29_, dived under the destroyer screen and fired one torpedo, which pa.s.sed astern of the _Neptune_. The alarm was immediately sounded, and presently the battleship _Dreadnought_, which had seen the periscope, started at full speed for the submarine, rammed the vessel and sent it promptly to the bottom. As it was sinking the bow rose out of the water, plainly disclosing the number _U-29_. There was not one survivor.

Weddingen's attempt was an heroic one, but so disastrous to himself and to his vessel that very few German commanders ever tried to emulate his example. It clearly proved to the German Admiralty that it was useless to attempt to destroy the Grand Fleet with submarines, or even to weaken it piecemeal, and probably this experience had much to do with this new kind of warfare--that of submarines against unprotected merchant ships--which the Germans now proceeded to introduce.

The simple fact is that the battle fleet was never so safe as when it was cruising in the open sea, screened by destroyers. It was far safer when it was sailing thus defiantly, constantly inviting attack, than when it was anch.o.r.ed at its unprotected base at Scapa Flow. Indeed, until Scapa Flow was impregnably protected by booms and mines, the British commanders recognized that cruising in the open sea was its best means of avoiding the German U-boats. No claim is made that the submarine cannot dive under the destroyer screen and attack a battle fleet, and possibly torpedo one or more of its vessels. The ill.u.s.tration which has been given shows that Weddingen nearly "got" the _Neptune_; and had this torpedo gone a few feet nearer, his experiment might have shown that, although he subsequently lost his own life, crew, and ship, he had sunk one British battleship, a proceeding which, in war, might have been recognized as a fair exchange. But the point which I wish to emphasize is that the chances of success were so small that the Germans decided that it was not worth while to make the attempt. Afterward, when merchant vessels were formed into convoys, a submarine would occasionally dive under the screen and destroy a ship; but most such attacks were unsuccessful, and experience taught the Germans that a persistent effort of this kind would cause the destruction of so many submarines that their campaign would fail. So the U-boat commanders left the Grand Fleet alone, either because they lacked nerve or because their instructions from Berlin were explicit to that effect.

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