The object of the flotillas of shallow-draught patrol vessels operating in the vicinity of the deep mine barrier is twofold. Primarily their duty is to prevent the hostile submarines from running the blockade on the surface and, secondly, to prevent enemy surface craft from emerging from the base and sweeping clear a passage through the mine-field, or of laying counter-mines, which, on being exploded, would detonate some of the blockading deep-laid mines and so destroy a section of the barrier.
From this it will be apparent that a force of hostile submarines hemmed in in this way would run a double risk of losing a number of vessels on every occasion on which a sortie was made. This is what actually occurred to the German under-water flotillas in the years 1917-1919, and, in combination with the other methods employed by the Allied navies, was mainly responsible for the failure of the great under-sea offensive.
The only bases of the German navy being situated on the North Sea littoral, it was possible for the Allies to lay a vast mine barrier, stretching from the coast of Norway to the Scottish islands, and another smaller one across the Straits of Dover; also to concentrate in the vicinity of these two submarine “trench systems” a very numerous surface patrolling force, thus enclosing the thousands of square miles of sea forming what was sometimes boastfully referred to as the “German Ocean” in an almost impenetrable ring of steel and T.N.T.
Here let us consider the gigantic nature of the task that was successfully accomplished. The distance from the Norwegian coast to the Orkney Islands is approximately 600 miles. It was over this vast expanse of sea, bent at the eastern end so as to rest on the Heligoland Bight, that the system known as the “Northern Barrages” extended. No exact statistics of the actual number of mines used is at present available, but reckoning at the low rate of one mine to every 750 feet of sea, with five lines stretching from shore to shore, the number required would be 21,000 of these costly and difficult weapons. The number required annually to maintain such a barrage would also be very heavy, and it is safe to assume that considerably over 50,000 mines were employed on the northern barrages alone. From this rough estimate some idea of the work of designing, manufacturing, testing, laying, renewing and watching this one field will be obtained.
Fig. 31.—Diagram illustrating a mine barrage, or deep-laid mine-field. The submarine A, diving to avoid a surface warship, has become entangled in the mooring of a deep-laid mine which is being dragged down on top of her. These mines are often moored at a depth of 60 feet below the surface, which can then be patrolled by surface warships.
There were, of course, in the actual barrage several mine-fields placed strategically, and probably a far greater number of weapons than that given in the above estimate was needed. There were also the smaller fields lying between the northern barrage and the one across the Straits of Dover. These were so placed as to catch hostile submarines operating off the east coast of England, or a surface raiding squadron, such as those which in the earlier years of the war bombarded certain British ports.
Finally, when victory had been achieved, there came the cold-blooded task of clearing these immense areas of sea, not only of German mines, laid haphazardly, but also of the thousands of British mines laid methodically and away from neutral traffic.
The English Channel barrage differed from the northern line in several important respects. Being so much shorter (31 miles against 680), it could more easily be made perfect. The swift-running tide, however, greatly increased the difficulty of laying effective mine-fields.
The Lighted Barrage
This southern system consisted, on the surface, of a number of vessels specially built to ride out the heaviest gale at anchor. These were moored at intervals across the Straits of Dover, forming two lines from the English to the French coast. The first line extended from Folkestone to Cape Gris Nez, and the second line about seven miles to the westward of these points (see Fig. 32). Each vessel was fitted with powerful searchlights for use at night, and the dark spaces of sea between were patrolled by large numbers of armed craft.
From a photo by Stephen Cribb, Southsea
Minesweeping Gear on a Trawler
Fig. 32.—Diagram illustrating the Dover lighted barrage. This barrage consisted of two lines of lightships, E and F, from England A to France B. The first line extended from Folkestone C to Cape Gris Nez D. The second line F was situated seven miles westwards of the first line. The small top diagram shows how the two pathways of light, with a numerous patrol between, compelled the U-boats to dive in order to avoid observation and destruction by gun-fire. The lower diagram shows the deep-laid mines arranged to receive the U-boats when they attempted to run the blockade in a submerged condition.
By this means the only avenues by which hostile submarines could hope to pass on the surface through the barrage at night were the dark lanes of water between the lightships. It was these points which were closely guarded by strong patrol flotillas, whose duty it was to attack submarines attempting to get through and, with the aid of guns and depth charges, to force them to dive below the surface.
Here certain destruction awaited them on the submerged mine-fields. If, however, one line of defence was safely passed by a hostile submarine, there was another to be negotiated seven miles farther on, and once a submarine got between the two lines her chances of escape were indeed small, for whichever way she turned the surface would be covered with fast patrol craft and at night lighted by the rays of many searchlights, while the under-seas were almost impassable with mines.
If, however, notwithstanding these defensive systems, a submarine succeeded in passing through and getting to work on the lines of communication with the armies in France, there were hydrophone organisations and patrols all down the Channel from the lighted barrage to the Scilly Islands. By this means a U-boat would be seldom out of the hearing of these instruments for more than an hour or so at a time.
The success which attended the perfecting of this vast system was such that German submarines based on the Flanders coast gave up attempting to pass down the English Channel. They tried to go to and from their hunting grounds on the Atlantic trade routes round the north coast of Scotland. Here the great northern systems took their toll.
During the first nine months of the year 1918 the German submarine flotillas at Zeebrugge and Ostend lost thirty vessels, and no less than fifteen of these had, at the time of the signing of the Armistice, been discovered lying wrecked under the lighted barrage.
CHAPTER XIV
Off to the Zones of War
Hitherto I have dealt with the scientific training of the personnel, the armament and the general organisation of the anti-submarine fleets, leaving it to the imagination of readers to invest the bare recital of facts with the due amount of romance. If, however, a true understanding of this most modern form of naval war is to be obtained, the human aspect must loom large in future pages.
War, whether it be on the sea, under the sea, on the land or in the air, is a science in which the human element is of at least equal importance with that of the purely mechanical. It is a science of both “blood and iron.”
The armed motor launches described in earlier pages, after being built in Canada to the number of over 500, and engined by the United States, were transported across the Atlantic on the decks of big ocean-going steamships—more than one of which was torpedoed on the voyage. On their arrival in Portsmouth dockyard the guns and depth charges were placed aboard and the vessels thoroughly equipped and fitted out for active service.
Officers and men were drafted from the training establishments of the new navy at Southampton, Portsmouth, Chatham, Greenwich and elsewhere. Each little vessel was given a number, and within a few weeks of their arrival from the building yards on the St Lawrence they sailed in flotillas out past the fortifications of Spithead, en route for their respective war bases.
Great secrecy had surrounded the construction of these small but powerful craft, and but few naval men, except those directly engaged in the anti-subm
arine service, had either seen or heard much of them until they commenced arriving at the different rendezvous.
Among the early flotillas to leave Portsmouth dockyard was one of four ships destined for a base on the east coast of Scotland, and as these speedy little craft raced away north the expectations of both officers and men ran high.
It was in the early summer of 1916, and although the air was crisp, the sea sparkled in the bright sunlight and the sky was a cloudless blue. Only a heavy-beam sea off Flamborough Head had marred the maiden voyage, and they were now on the last hundred miles, with the low-lying Farne Islands fading into the mist astern. By nightfall, if the wind remained light, they would make the Scottish port which was to form their base of operations.
Hitherto these four brand-new little warships, all white wood, grey paint and polished metal, had been plodding over the 600 miles of sea from Portsmouth at what was termed “cruising speed”—a mere 10 knots. The engines had not been opened out to “full ahead” because these delicate pieces of mechanism needed time to settle down to their work before it was safe to drive them to the utmost limit of speed and power, but now that pistons and bearings had been given time to “run in” it was considered safe for the flotilla to increase speed in order to make harbour by nightfall.
A hoist of new, bright-coloured flags fluttered from the squat mast of the leading ship. The steady throbbing of the engines grew suddenly to a low staccato roar. The white waves astern rose up almost level with the counters and clouds of fine spray blew across the decks. This rapid movement through the sun-lit water, with the breeze of passage and the tang of the salt sea in every breath, was exhilarating, and the spirits of those aboard rose with the speed.
Running at nearly half-a-mile a minute, the flotilla forged northwards through clouds of fine, stinging spray, until at a late hour, when the sun was dipping below the horizon and the sea was a sheet of golden light, a smoky line appeared far away to the westward. It was that section of the Scottish coast which in future it would be the duty of these boats to patrol, and as the distance lessened those on board gazed in silence at the gigantic cliffs and black rocks, now tinged with the rays of the dying sun and encircled by the endless ripples which alone broke the peaceful surface of the sea, but one and all were picturing this forbidding coast on the stormy winter nights to come.
Slowly the light faded from the western sky. The cliffs rose up black and sombre, and when the little flotilla turned westwards up the broad waterway leading to the base darkness had closed over land and sea. For some time they picked their way up this sheltered loch. No lights were visible, but more than once a destroyer appeared out of the blackness to make sure of their identity, and each time they were inspected very closely before the guard-ships were satisfied. An armed trawler guided them past dangerous obstructions and then faded into the night. Mile after mile of water was then traversed on courses laid down in confidential orders.
Suddenly a searchlight flashed out from close ahead, followed almost instantly by other blinding rays, which swept the sea for a few seconds, and then all the beams concentrated on the little flotilla, showing up with the clearness of daylight the four low-lying submarine-like hulls gliding speedily through the water. There was a moment’s silence, during which the Morse signalling lamps of the M.L.’s were being prepared to flash out their message. A searchlight blinked and there followed another brief interval of silence, then, without warning, a tongue of livid flame stabbed the darkness and a shell whistled overhead. It was followed by other flashes and the sharp reports of quick-firing guns. Columns of water spouted into the air close to the M.L.’s, whose engines had, luckily, ceased to throb. The firing stopped as suddenly as it had commenced. Signals began flashing angrily in many directions. Destroyers tore out of the darkness around into the broad circle of light. Armed trawlers nosed their way in and wicked grey tubes were trained on the now stationary flotilla. Presently the angry flashing of mast head-lights subsided into the regular dot and dash of respectable communication. Several destroyers seemed to be having nasty things said to them, which they answered with a feeble wink, and an armed trawler made futile flashes of explanation.
A little twinkling star, more lofty and dignified than the rest, called up the leading M.L. and was answered with an alacrity that evidently unnerved it, for it flickered and died out. Suddenly it came to life again and winked away at an alarming rate, but all to no purpose, for, true to the old axiom that more haste means less speed, it had to stop and go over the message again, this time sufficiently slow for novices to understand. What it said is a State secret. It is rumoured, however, that several officers were “mentioned in dispatches” for the part they played in this local action, caused by mistaken identity, but alas! their skill and bravery remained unrewarded by an unsympathetic Government.
CHAPTER XV
A Memorable Christmas
No calling tempers the human steel in so short a period as that of the sea. At all times and in every part of the world the sailorman wages a never-ending fight with Nature in her wildest and most dreaded modes. When to this is added a conflict of nations and their ships, with all the ingenious death-traps of modern naval science, it merely increases the odds against him and serves to steady his hand and brain in order to overcome them.
In a few short weeks the sea had set its stamp on the men of the new navy. Faces became bronzed by the sun, wind and spindrift. Muscles grew hard and eyes and nerves more steady. Each time a vessel went forth on patrol or other duty new difficulties or dangers were met and overcome without advice or assistance, and the confidence of men in themselves and in the ships they worked grew apace.
In many of the principal zones of war, such as the North Sea and the Atlantic, the wind grew colder and the seas more fierce as the short summer passed. Duffel or Arctic clothing was served out to both officers and men. Sea-boots and oilskins became necessary. Balaclava helmets, mufflers and other woollen gear appeared, and men became almost unrecognisable bundles of clothing. The ascent at 4 a.m. from the cabin to the cold, wet deck can be likened only to the first plunge of a cold bathing season. Casualties became more frequent as the enemy intensified his submarine and mining campaign. The news and sight of sudden death no longer blanched the faces of men who knew that it might be their turn at any moment of every day and night. The stir of suppressed excitement when danger threatened no longer manifested itself in every movement, but rather in the cool, deliberate action of self-confidence. In a word, the raw material was being tempered in the furnace of war.
To those in northern seas came the blinding sleet, the slate-grey combers and the innumerable hardships and dangers of winter patrol. A better idea of what these really were will be obtained from the following account of a Christmas spent on a German mine-field.
A bitter wind swept the grey wastes of the North Sea and a fine haze of snow, driven by stinging gusts, obscured all except the long hillocks of water which rose and fell around the tiny M.L.—a lonely thirty tons of nautical humanity in as many square leagues of sub-Arctic sea.
Nineteen degrees of frost during the long winter night had flattened the boisterous, foam-capped waves, and now, in the early December dawn, all within vision was of that colourless grey so familiar to those who kept the North Sea on the winter patrol.
It was one bell in the first watch and three shapeless figures clad in duffel coats with big hoods and wearing heavy sea-boots stood silent in the draughty, canvas-screened wheel-house as M.L.822 wallowed northwards through the seas which came in endless succession out of the snowy mist. It was just the ordinary everyday patrol duty, when nothing was expected but anything might happen, so eyes were strained seawards in a vain endeavour to penetrate the icy curtain blowing down from the Pole. Twelve hours more of half-frozen existence stretched in front of these silent watchers, as they clung with stiffened limbs to ropes stretched purposely handy to keep them upright when the little ship lurched more fiercely in a steeper sea.
Of the th
ree figures in the meagre shelter of the wheel-house there was little to distinguish who or what they were, except, perhaps, a cleaner and more yellowish duffel coat and a big white muffler in which the lieutenant-in-command tried, without success, to keep his teeth from chattering and the icy draught from finding its way into the seemingly endless openings of his woollen clothing. What he had been before the Great War and the North Sea claimed him was a mystery to those on board, but the people of more than one capital knew his name. Near by stood a younger man—a boy before the war—who, although pale and dark-eyed, did not appear to feel the intense cold so much, although the dampness of the long-past summer fogs had chilled him to the bone. He was the sub-lieutenant, and hailed from the Great North-West, where Canadian winters had hardened his skin to the stinging dry cold.
Fig. 33.—Duffel or Arctic clothing.
The immense bundle of nondescript clothing at the wheel was “Mac,” the coxswain, whose voyages in Arctic seas with the Iceland fishing fleet numbered more than his years of life, and whose deep-voiced Gaelic roar could bring the “watch below” on to the cold, wet deck to their action stations in less time than it would take a new recruit to tumble out of his hammock.
Although the silence of the sea seems to settle on its watchers in those northern marches, there was an unduly long absence of comment on the nature of the weather and the prospects of “something exciting” turning up out of the icy mist. The reason lay in the subconscious mind of all on deck, for it was Christmas morning, 1916, and the thoughts of all were dwelling on past years in the cheery surroundings of English and Colonial homes—in vivid contrast to the dismal grey of the North Sea. To break the spell of memory both officers felt would be blasphemy, and yet a feeble attempt at conversation was made every now and then for the sake of appearances.
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