Chapter II: Part 2

"My dear Max," he said, "since when did you learn that to be a true patriot it is necessary to consider the advantages of your country's enemies? It is nonsense. Your highest duty, as my son and as a German, is to do all you can against the arrogant English. You shall obey me. Do you understand? Tell me, once: how many people know that you are here in Haddisport? How many know that your life was saved when the British cruiser was blown to pieces by our faithful explosive mine?"

"Nobody knows," Max answered sullenly. "Nobody on board the destroyer which picked me up knew me, even by sight. I did not intend that any one should guess I was a German. Nobody who was on board the _Atreus_ knows that I was not blown to bits--except--yes, except Mark Redisham. He saw me swimming. But he doesn't know that I was saved."

"Ah!" nodded Herr Hilliger. "And he need never know. He must never know--never. It is better that he should believe that you were drowned."

Max clutched at his father's arm, pressing him back upon the grass behind the tree.

"Some one comes!" he whispered agitatedly.

They both saw the lithe figure of a youth approaching silently up the drive. He paused for a moment, looking at the front door of the dark, deserted house, strode to the porchway, and quickly ran up the steps. In the silence the two watchers heard the tinkling of an electric bell; but neither moved. Strange that they should thus hide themselves in their own garden!

They waited, knowing that the door would not be opened. Herr Hilliger ventured to lean out and look towards the porch. As he did so, the revolving beam of light from the lighthouse, half a mile away, illumined the trees, travelled slowly over the towers and gables of the dwelling, glinted for an instant on the upper windows, then spread its glow across the sea. Against this glow he saw the figure on the doorstep, clearly defined.

"It is one of your Sea Scouts," he whispered.

The Sea Scout ran lightly down the steps, turned, and came quickly nearer, walking so quietly on the gravel that Max could only believe that he wore tennis shoes. Then, as he came yet closer, to within a couple of yards of the two Germans, again the beam from the lighthouse swung round and shone in his face.

It was the face of Mark Redisham.

*CHAPTER VI.*

*WHAT MARK FOUND IN THE PIGEON-LOFT.*

The two watchers under the sycamore-tree held themselves so very still and silent that even if he had been searching for them Mark Redisham might have passed by without a suspicion that they were so near. His well-trained senses were alert, but he was not consciously listening for any betraying sound or looking for any movement.

He went on along the gravel drive with confident stride until he reached the stables. Here he paused, glancing backward before entering the gateway of the yard. He had expected to find the gate shut and bolted, and was surprised to see that the door of the motor-garage also was open.

The place was in darkness, but he noticed that the motor-car was not there. This appeared to indicate that, although the family might have gone home to Germany, yet they had not dismissed all their servants. Mark reflected that probably the chauffeur, who acted also as gardener, had been left in charge of the house and grounds until the property should be sold or otherwise disposed of.

Mark had no intention of asking the caretaker's sanction to do what he had come to do. Indeed, it gratified him that his precautionary ringing of the hall hell had not been answered. He went boldly into the stables.

Knowing that he was about to use his electric torch, he closed the door behind him, lest the light should be seen. He knew the place well. Even in this past summer the Lion Patrol had had a scout game at Sunnydene. Pickets had been stationed at various points, and it had been his own part to steal into the grounds and make his way in the darkness into the harness-room without being caught.

He was now engaged in no ordinary scouting game, but in a serious duty imposed upon him by the officer in command at the naval base, and it was even more important that he should not be detected.

Feeling along the whitewashed wall, he touched the ladder leading to the loft. Up this he climbed through the trap-door.

He stood for some moments looking about him in the darkness of the loft. In the high door by which hay and straw were brought in there was a small hole, on a level with his eyes. Swallows used it as an entrance to their nests in the rafters. Going up to it and peering outward, he could distinguish the dark level of the sea, and presently the ruby gleam of the Alderwick lightship appeared, grew brighter, and faded against the dim horizon.

Mark realised that, if from here he could see that ruby gleam, it was certain that the crew of the lightship could equally well see the flash of his electric torch. Was it not possible that Heinrich Hilliger had used this hole in the loft door through which to flash his signals? Mark covered the hole by hanging his cap on a nail just above it.

Then he turned and closed the trap in the floor. It made more noise in falling than he had intended. Whether it was the displacement of air or his own fancy, there seemed to be a corresponding sound down below, as if another door had been suddenly shut, and as if the key of that other door had been turned in the lock.

"I suppose I'm a bit nervous," he said to himself. "It couldn't have been anything." He drew out his torch, pressed the switch, and turned the shaft of light upon the partition beyond which Hilliger's pigeons were kept. The key was in the door. Feeling like a guilty burglar, he turned it and entered, shielding the light from the open space in the gable by which the pigeons flew in and out.

There were no pigeons here now. The coops and perches were empty. He supposed that Herr Hilliger had taken the birds away with him, to use them in carrying secret messages back to England; although, as yet, there was no proof that Herr Hilliger had ever actually used any of his pigeons for this purpose.

Mark made a rapid survey of the untidy loft, with its lumber of old harness, rusty garden tools, bundles of sacking, broken fishing-rods, and discarded cricket bats. On a low shelf were some model yachts with torn sails and tangled rigging. He looked at the rough model of a steam trawler. The boat was curiously constructed with a boxed-in and bottomless well. Inside this well there was a crude model of a submarine. Some one--Max Hilliger, perhaps--had evidently attempted to invent a device by which a real submarine might be hidden within the casement of a larger vessel, thus enabling it to be brought close to an enemy without being discovered. The idea was ingenious, but obviously not practical.

In a corner cupboard he discovered a box of electric light bulbs of various colours. The sight of these led him to search for electric wires. He saw none; but what he did find was a portable electric lamp coiled round with a wire so exceedingly long that, as he estimated, the switch might be worked here in the loft while the bulb could be cunningly planted amongst the gorse bushes halfway down the cliff, there to flash its signals of coloured light.

Mark wondered if he should take the lamp away with him, but decided to leave it untouched. If as he believed, Herr Hilliger was already on his way back to Germany, and if Max were drowned, there could be no more risk of their communicating with the enemy.

He turned his torch upon the long trestle table at the far end of the loft. It was littered with feathers and grain, and thick with dust. But in the midst of the litter were several things which he considered it his duty to examine. The first article he touched was a match-box, half full of very small elastic bands. Beside it was a spool of thin, narrow paper.

"Here's proof enough!" he reflected with satisfaction. For he recognised the paper and the elastic bands as being precisely similar to the material found on the leg of the pigeon shot by Darby Catchpole from the deck of the _What's Wanted_.

For a little while longer he continued his search. From a pile of old newspapers and tattered books, he idly drew forth a long, tin cylinder, thinking at first it was a telescope case. The lid had been jammed on crookedly, and he had difficulty in pulling it off with the help of his knife. When he succeeded at last in opening the canister, he saw that it contained several tightly-rolled sheets of paper. He spread them out on the table. They were maps, plans, and charts, very carefully drawn.

The uppermost one was a general map of the coast, including Haddisport and Buremouth, with the villages between and a wide strip of the sea, divided into numbered sections. The others--and there were some twenty of them--were detailed enlargements of the same sections, upon which were shown the principal buildings of the two towns, the particulars of the harbours and railways, with every road and lane and bridge, every field and coppice and house, distinctly indicated.

Mark Redisham had never seen such wonderful maps, or imagined that any existed so complete and correct. Nothing seemed to have been overlooked. On the margins of each sheet were notes, written in German, with numbers referring to certain features in the plans.

Mark saw much that he did not then understand; but there was one sheet in particular which was perfectly clear to him. It was a large scale chart of the section of the North Sea immediately facing Haddisport, giving the exact soundings of the channels and shallows and showing an outline of the coast, with every altitude measured.

The soundings of Alderwick Knoll were so precise and plentiful that it was evident to him that some important purpose was connected with this sand-bank. He could hardly doubt, indeed, that the chart had been prepared for the guidance of an enemy attempting an invasion!

So greatly was he impressed by this idea, that he became nervously excited over his discovery. What was he to do? Should he carry these charts and maps away with him, now--to-night? He had not been instructed to take anything away with him; but only to "have a look round" and report upon any discovery he might happen to make.

Thinking over the situation for a few swift moments, he determined to obey his orders to the letter. Accordingly, he returned the sheets to the map-case, put the case back where he had found it, and prepared to leave the loft.

He left no trace of his secret visit. Taking his cap and pocketing his torch, he climbed down the ladder into the garage. He pushed lightly at the door; but it did not swing open. He pushed it harder; still it resisted. Then he put his shoulder to it and gave it a shove. It did not move. He grappled with it, trying with all his strength to force it open and, realised, to his alarm, that it had been locked from the outside!

He grew hot and cold by turns. Had he been watched, stealing into these stables where he had no business which he could truthfully explain? If so, who could it be that had watched and trapped him? It could not be Heinrich Hilliger himself, or Max. Herr Hilliger had gone back to Germany. Max was drowned. The chauffeur had not returned with the car. Once more he put his shoulder to the door. No. It was certainly locked! He was a prisoner!

But Mark Redisham was not a Sea Scout for nothing. There were more ways than one of getting out. He tried the door of the harness-room. That, too, was locked. Yet there was still another door, leading into the stable. It opened with a simple latch and he crossed to the door giving on to the yard. Again he was foiled.

He looked to the window. It was heavily barred.

But not even now did he despair. Beyond the vacant horse-boxes was a small opening in the wall--a hatch through which the stable refuse was forked out. This hatch, he knew, was fastened only on the inside by a hook and staple. In a moment he had flung it open, to climb out without further hindrances and make his way among the fruit trees and across the tennis lawn to the back gate of the Sunnydene property, and into the Alderwick road.

Five minutes after his escape, he was at home in his father's library, sending his report by telephone to the naval base.

His father, Major Redisham, had gone off to join his regiment, and the family supper was in consequence a melancholy meal. Mark said nothing of his visit to Sunnydene; but he was at liberty to tell his mother and sisters of the exciting events of the day--the loss of the _What's Wanted_, the sinking of the German mine-layer, and the terrible disaster to the _Atreus_.

"So you see," he concluded, "Rod was present at the firing of the first naval gun of the war!"

"Yes," said his mother; "but unfortunately Rodney's ship cannot be replaced, or the brave men who went down with her. He may not get another appointment for a long time. Is he coming home to-night, Mark?"

Mark shook his head.

"No, mother," he answered. "He was kept aboard the destroyer--the _Levity_. The whole flotilla went off to sea again as soon as the wounded were put ashore for hospital."

"I suppose they've gone to join the main fleet," his sister Vera conjectured. "Of course, the German battleships are out, and there'll be a great battle."

"The destroyers went south, however," Mark explained, "and the enemy fleet is much more likely to be hanging round off the Dogger Bank than down there in the narrow seas. It's my idea that the destroyers have gone into the Channel."

"Why?" questioned Vera. "What's the good of their going into the Channel when the Germans are in the North Sea? We want to fight them, don't we?"

"Well, you see," resumed Mark, "the British Army will be crossing to France. You don't suppose that ever so many of our transports--big liners crowded with troops--will be allowed to go over by themselves, at the risk of being sunk by German submarines? They've got to be protected on both flanks. I expect they'll steam across through quite an avenue of cruisers and destroyers."

Later, when Mark was saying good-night before going sleepily to bed, there was a ring at the front-door bell.

"Master Mark is wanted," the parlourmaid announced agitatedly. "There's a policeman and a lot of soldiers."

No longer sleepy, Mark hurried into the hall, where he found Constable Challis, Mr. Bilverstone, and two men in khaki.

"What's up?" he cried, seeing that the two soldiers were armed with rifles and fixed bayonets. "Are the Germans coming?"

"We want you to go with us," Arnold Bilverstone explained. "Get on your overcoat, and bring your electric torch. We're going to make a raid on Herr Hilliger's pigeon-loft."

Mark was quickly ready to march off at the head of the company. As they filed into the Sunnydene ground they saw that the house was in total darkness.

Leaving one of the sentries posted outside the stable yard, Mr. Bilverstone led the way round to the rear of the outhouses, where he posted the second sentry. Mark crossed the tennis-court, dodged under the fruit trees, and crawled through the hatch door which he had left unfastened. Mr. Bilverstone and Constable Challis followed him through the stable and into the garage. They mounted one by one into the loft. Mark flashed his torchlight along the floor, up into the rafters, and again along the floor. Then he stooped and picked up the stub of a cigarette, sniffed at it and shook his head.

"Somebody has been here!" he cried. "The end of this cigarette's still wet."

He went beyond the partition and began to search. But his search was in vain. The maps, the electric signalling-lamp and coloured bulbs, the model of the submarine, the spool of paper, the elastic bands--all had been cleared away. Nothing remained to show that the place was more than an abandoned pigeon-loft.

*CHAPTER VII.*

*UNDER THE WHITE ENSIGN.*

Because he was a Sea Scout, clever at semaphore signalling, with a knowledge of seamanship, resourceful, and generally handy, Mark Redisham had no difficulty in entering the Royal Naval Reserve, the more especially as he was strongly recommended by Captain Damant. It satisfied him greatly to be appointed at once as signal-boy and wireless operator on board His Majesty's steam trawler _Dainty_.

She was named the _Dainty_ when launched, and as the _Dainty_ she had toiled and battled for three stormy winters on the wild North Sea. But now her impudent white and red funnel and her gaudy hull were painted a sombre war grey, her trawling gear had been altered, her fish-well turned into a cabin, and the name on her bows had given place to the number 99. She was no longer a mere fishing craft, but classed as one of the great new fleet of naval mine-sweepers, flying the white ensign, and manned by a crew of sturdy East Coast fishermen wearing the blue jacket and loose trousers and flat-topped caps of the British Navy.

It was a proud moment for Mark when early on the morning following the "raid" on the pigeon-loft he went on duty, and the _Dainty_ steamed out of Haddisport harbour and bore northward abreast of the lighthouse and past his home on the cliff. She was one of a squadron of twelve, and they went out in the company of the torpedo gunboat _Rapid_.

Word had come that the Germans had sown an extensive mine-field to the west and south of the Dogger Bank, scattering their deadly explosives over the seas, to the peril of peaceful trading vessels as well as of any British battleships and cruisers that might enter the area of danger. Two Danish cargo steamers and half a dozen English fishing boats had already been blown up, and our busy scavengers of the sea were now to go out and rake up the carefully-sown seedlings of death.

The work was dangerous, for at any moment one of the stout little vessels of the squadron might find a mine with her keel instead of with her stretched wire hawser, which meant ten more good men sent to the bottom. And there was always the risk of a premature explosion if a mine had to be handled in releasing it from its moorings.

Mines are not pleasant things to handle at any time--certainly not such powerful ones as the Germans employ, with glass "beards," or projecting spikes, the breaking of one of which results in an explosion great enough to sink a Dreadnought! They are charged, not with gun-cotton, but with the even stronger explosive known as T.N.T., which has the quality that if the mine filled with it strikes a ship it blows in the side of the vessel and then continues its destructive work in the interior.

The skipper of mine-sweeper 99 was Harry Snowling, R.N.R., an old salt who had fished for thirty years on the North Sea, and knew its deeps and shallows as well as he knew the lines on his own honest, weather-beaten face. But, of course, he had had no experience of mine-sweeping, and had only vague ideas as to how the mines were to be located.

"What's she doin' of, bor?" he questioned, when they were far out in the blue water, watching a seaplane sweeping overhead and flying to and fro athwart the gunboat's course.

"Well," said Mark Redisham, "I'm not certain; but I suppose she's looking for mines. They're not floating right on the surface, you know. They're held just about a foot below low water level, so that when a vessel passes she'll go bang on to them. But the pilot up there can see them, as a gannet sees a fish, and I expect he'll drop a signal when he spots one."

For something like an hour the seaplane searched, followed by the gunboat, with the trawlers moving in pairs in her wake.

When at length a signal was sent down that mines had been sighted, "dans," or small buoys with flags attached, were put out to mark the spot from which operations were to begin. Each couple of trawlers got ready their dredge tackle, dropping over the stern a long wire rope, heavily weighted. The weight drawn by each boat was connected with that of its partner by a yet longer wire hawser, weighted to keep it submerged and stretched below the level of the floating mines. The two vessels, ranging themselves on either side of the mine-field, steamed ahead on a parallel course, so that their submerged gear should catch upon the mooring-lines and sweep up the mines floating between them.

This process was carried on simultaneously by the other trawlers, clearing a wide lane through the mine-field, while the gunboat and the seaplane continued their searching for new fields.

When the mines were thus caught and brought to the surface, they were exploded from a safe distance by gunfire. You may be sure there were many narrow escapes from serious accident.

During the first afternoon, the _Dainty_ and her working partner, the _Ripple_, brought up two mines together. They came into violent contact with each other, exploding so close astern of the _Ripple_ that she was caught in the edge of the upheaval and badly damaged. Her crew made for the boat, thinking that all was over with them; but her skipper controlled them, and himself crawled below into the narrow space near the screw shaft, discovered the damage, and stopped the leak sufficiently to enable the pumps to keep the water down and save the ship.

Within a quarter of an hour of this accident, one of the other trawlers struck a mine and was shattered to fragments.

At the end of two days, the field having been cleared, the gunboat returned to port. Shortly after she had gone, Mark Redisham and his companions watched a squadron of British dreadnoughts and cruisers steaming safely across the area from which the danger had been so industriously removed.

Their trails of smoke had hardly faded from the horizon when Mark, still looking in the direction in which they had disappeared, noticed a curious disturbance in the calm water, about a couple of miles away.

At first he thought it was a school of gambolling porpoises showing their fins, but presently the periscopes and conning-tower of a submarine rose to the surface. The conning-tower was marked "U15," and he knew by this that she was German.

It seemed to him that she had probably been lurking in wait for the battleships that had just passed. If so, she had certainly missed her chance of doing them any damage. One of her officers climbed out to the conning-tower platform, looked searchingly around the sea, but quickly disappeared again, and the submarine dived, having paid no attention to the trawlers.

Mark, taking counsel with the skipper, went into the wireless operating-room and sent out a message, reporting what he had seen and giving the position. He did not expect his message to be picked up; but within an hour a British light cruiser came racing down from the north at twenty-five knot speed. The skipper and Mark watched her through their binoculars as she drew nearer, and identified her as H.M.S. _Carlisle_. They saw her suddenly alter her course, as though to avoid the mine-sweepers and possible floating mines.

"Her needn't be afeared," said Snowling. "Thar aren't no mines here now. Suppose you signals her, bor, and tells her it's all right!"

"Hold hard!" cried Mark. "Look! Look what she's after!"

In direct advance of the cruiser, he distinguished for a moment the two periscopes of the enemy submarine making a ripple as they moved through the calm water. In that same moment there was a gush of fire and smoke from one of the warship's 6-inch guns. A fountain of spray rose high into the sunlit air from where the shell had fallen. One of the periscopes seemed to have been struck. The submarine, evidently crippled, was emptying her ballast tanks to rise to the surface when a second shell struck her half-submerged conning-tower, smashing it like an egg.

"That's what I calls good marksmanship," declared old Harry Snowling. And going to the flag-halyard, he dipped his white ensign in salute.

The nearest of the trawlers hastened to the spot where the shattered submarine had gone down, hoping to save some lives; but nothing was found but a slimy patch of floating oil.

The _Carlisle_ came within speaking distance of the trawlers, standing by for about an hour, and gave information of a new mine-field sown between the Dogger Bank and the Bight of Heligoland. Ten British trawlers, it was stated, had been captured by a German cruiser--the _Schwalbe_--which had taken them in to Emden. Their crews had been kept prisoners, and the boats had been fitted out as mine-layers to scatter mines indiscriminately wherever ships could sail.

The mine-sweepers were supposed to work in stretches of ten days at sea and six in port; but the _Dainty_ and her companions continued at their task a longer time, for the danger was greater than ever the Royal Navy had counted upon.

Many neutral ships and fishing craft had been blown up, a British gunboat had been sunk, another badly damaged, and it was imperative that the seas should be kept clear. But at length a relief squadron from Grimsby came out to take over the work, and the Haddisport boats were dismissed for home.

Early on the next morning, Mark Redisham started up in his bunk, hearing the engines coming to a dead stop. He dressed himself in his oilskins and went out upon the rain-splashed deck. To his surprise he saw that a submarine had come close alongside. It was the H29, of which, as he remembered, his friend, Lieutenant Ingoldsby, was the commanding officer. One of her crew had been taken ill, and Lieutenant Ingoldsby wished the _Dainty_ to take the man on board and nurse him until he could be put ashore in Haddisport.

The sick man had been carried over a gangway thrown across between the two vessels when Mark, happening to glance over the _Dainty's_ farther bulwark, in search of the rest of the squadron which had gone on in advance, saw instead the dim shape of a three-funnelled cruiser looming ghostlike through the rain mist. She was flying no ensign, but by the look of her he was almost sure she was not British.

Not asking himself why he did so, he strode across the gangway to where Lieutenant Ingoldsby knelt, doing something with a spanner, on the narrow deck abaft the conning-tower.

"Good-morning, sir," he began. "I think the cruiser over there is signalling."

"Cruiser?" repeated Lieutenant Ingoldsby, springing to his feet. He climbed a few rungs up the ladder of the conning-tower, and looked out over the wheel-house of the _Dainty_, behind which the submarine was well hidden.

"Just slip below and ask Jardine for my glasses, Redisham," he ordered. "I believe it's the _Schwalbe_--the ship we've been stalking! In fact, I'm sure!"

Mark had never before been on board a submarine, and when he got to the foot of the perpendicular ladder of the hatchway, he became confused by the strange complexity of tanks and machinery. An electric light shone in the far end of a narrow passage. He was making his difficult way towards it when the great boom of a naval gun startled him. The _Schwalbe_ was opening fire on the mine-sweepers.

He stood still. The silence following the gun shot was broken by the banging of an iron door above his head, and the sharply-spoken command rang out in Lieutenant Ingoldsby's voice:

"Prepare to dive!"

*CHAPTER VIII.*

*HOW MARK MADE HIMSELF SMALL.*

On hearing the gun shot, followed so quickly by the command, "Prepare to dive!" Mark Redisham knew that the strange cruiser he had seen was unquestionably an enemy, firing upon the mine-sweepers.

An electric bell buzzed insistently; some one sang out: "Diving stations!" and there was a scurrying of bare feet along the narrow deck. It was useless now for him to go in search of Lieutenant Ingoldsby's binoculars. His impulse was to get off the submarine and aboard his own ship as quickly as possible. Yet for an instant he hesitated, lost in the confusion of dark passages and intricate machinery.

A second shot sounded. He turned and scrambled blindly back to the companion-hatch. But here he was stopped. The steep iron ladder was occupied by an officer who was even then screwing down the fastening of the watertight hatch-cover above his head.

"Can't I get off, sir?" Mark cried desperately. He had no fear, even though already he heard the gurgling of the water in the ballast tanks and knew that the submarine was on the point of being submerged. He clutched at the officer's naked ankles and repeated his question:

"Can't I get off, sir--on to my own ship--the _Dainty_?"

The officer, a sub-lieutenant in working kit, descended to the iron grating at the foot of the ladder.

"Not now," he answered quietly, as he pressed an electric switch, flooding the whole ship with light. "You must stop where you are. Sit down in that corner. Make yourself small. Don't touch anything, or you may get a nasty shock."

He bent down and disappeared through what looked like an oven door in the bulkhead. Mark could see the men hurrying to their posts. Two went forward to the torpedo-tubes, one to each main ballast-tank kingston, one to the hydroplane wheel, another to the motor switches. An engineer took charge of the air-escape vents.

Each kingston being opened and the water rushing in, the boat began to sink. Mark felt an uncomfortable, heaving motion beneath him. He heard the hum of machinery--the whirr of well-oiled wheels, the chunking of pistons and cranks. The Diesel engine was working whilst the conning-tower remained above the surface for the ship to get clear of the trawler alongside. Electric bells trilled their messages from the commander to the men at their various stations.

"Close everything!" he called aloud.

The petrol engine stopped. The ballast tanks were full, and the electric motors now took up the work of sending her along. To Mark Redisham it seemed that she was going round and round in a dizzy circle, already many fathoms deep under the sea. The smell of hot oil and the heaviness of the compressed air stifled him. Yet in his eager interest in all that was happening he would not have exchanged the discomfort for ease, or the possible danger for assured safety.

Suddenly, in answer to a turn of the horizontal rudder, she began to rise. Mark saw the sub-lieutenant crawl swiftly past him to the forward torpedo-chambers. Bending over, and lying on his elbows, he managed to get a sidelong glimpse into the conning-tower with its complicated network of wires, its confusion of switches, handles, levers, and brightly-polished instruments. The commander was there, he knew, although it was only now and again that Mark caught sight of the gold braid on his sleeve as he stretched out his hand to touch some switch or lever.

"Charge firing-tanks; flood torpedo-tubes; stand by to fire!" commanded Lieutenant Ingoldsby.

The periscope was now above the surface and his eyes were upon the image of his target reflected in the mirror. He was taking aim, manoeuvring the submarine into position as if she herself were a gun. For some tense moments all was quiet but for the purr of the motor and the working of the air-compressors for charging the torpedo-tubes. Then there came a thumping sound as of a heavy door being shut. This was repeated. Two torpedoes with their mechanism adjusted had been thrust into the breach of their tubes. Mark would have given much to see how it was done. But he did not dare to move. Obeying the recommendation to make himself small, he waited breathlessly.

"Number one--fire!" came the sharp command.

There was a violent gush as a torpedo was discharged on its errand of destruction. The whole vessel shuddered and was alarmingly unsteady until the compensating-tanks were filled and the true balance was regained. Then a second torpedo was fired. Mark listened, wondering, as the submarine dived with her nose down, if either of her weapons would strike the target at which it had been aimed. They had been fired at long range, but their rush through the water was quickly over. A low, rumbling explosion told that one of them had struck and burst against the German cruiser's bilge.

The H29 remained deeply submerged, her electric motor driving her forward at ten knots speed for something like a quarter of an hour, when once more the water was blown from the tanks and she rose to bring her periscope above the surface.

The sub-lieutenant was now in the conning-tower with the commander.

"We got her under the forward magazine," Mark heard Lieutenant Ingoldsby announce. "She's sinking by the bows. The German collier that we saw yesterday is standing by, picking up survivors. She's fitted with wireless, so we may as well keep out of sight. Carry on just as we are for another half-hour, Desmond, and shape a course for Haddisport Roads."

"Yes, sir," returned Mr. Desmond. "And what about our mine-sweepers?"

"Oh, they are all right!" the commander signified. "I've just counted them. I don't believe any of them was hit. Lucky for them that we turned up. She'd have sunk the lot."

"We've got one of the crew of the _Dainty_ aboard of us, sir," the sub-lieutenant told him.

"Yes, I know," nodded the commander; "it's young Redisham. I sent him below for my binoculars. If you sight his ship, we'll put him back."

Mark stood up and saluted him as he came out into the hatchway.

"I hope I'm not very much in your way, sir," he faltered.

"Not at all," smiled Mr. Ingoldsby; "although we haven't much room to spare on a ship like this, as you can see. But don't stay here in the gangway. Come along with me. Mind you don't knock your head, and don't touch any of the switches."

He led the way through an intricate passage into the engine-room: an open space that could hardly be called a cabin, where men were at work with the electric motors. Here he paused to glance at a gauge.

"You've done very well, shipmates," he said, nodding his approval. "You've sent a German cruiser to the bottom--an old ship, it is true; but she'll do no more mine-laying mischief, and I'm just as pleased with you all as if she had been a Dreadnought. Jardine," he added, pushing open the door that gave entrance to his cabin. "Shaving water, and then breakfast."

*CHAPTER IX.*

*AN EXPERT IN MINE-SWEEPING.*

Mark took up his stand in the only corner he could see where there was no machinery, and feasted his curious eyes on everything within their range--the hammocks slung from the steel cross-beams, the safety-helmets hanging near, the controls of a multitude of electrical devices, the wheels governing the rudders, and the great array of enclosed cylinders and accumulators.

At the far end was an electric cooking apparatus at which the cook had already resumed his interrupted work of preparing the officers' breakfast. From a small boiler, Jardine filled a silver jug with hot water, which he carried into the commander's cabin.

On his return, Jardine went up to Mark and said: "The commander wants you."

Mark was shown into the state-room and was surprised to find it so large and comfortable. Lieutenant Ingoldsby stood before a tiny dressing-table, lathering his face.

"Have you seen my aunt lately, Mark?" he questioned. "Is she nervous, living alone there on the cliff?"

"I saw her the night before we sailed," Mark answered. "She came in to bid good-bye to father. Yes, sir, I believe she is a bit nervous. She thinks there's sure to be an invasion, and that a whole army of Germans will come over in Zeppelins and flat-bottomed boats, guarded by submarines and Dreadnoughts. She said something about going inland to Bath or Buxton."

"Not very complimentary to the British Navy, eh?" laughed Mr. Ingoldsby, stropping his razor. "I hope Major Redisham reassured her. Tell me something about this mine-sweeping business, will you? The Admiralty don't seem to be altogether satisfied with the process. Too many precious lives are being sacrificed."

Mark described his work and told of the difficulties and dangers of dealing with contact-mines.

"The worst part of it is when we come bow-on to one of them," he said. "I've been thinking a lot about it. I don't know if there's anything in my idea, but it seems to me that the sweepers ought to be fitted with some sort of protective net in front, to ward off the mines, or even to pick them up--something like the cow-catcher on an American locomotive, you know."

Lieutenant Ingoldsby turned round sharply in the middle of shaving his left cheek.

"Good!" he exclaimed. "Very good. You've certainly hit upon the right notion, if you think it can be worked--and at once."

"It ought to be quite easy," Mark averred. "Just a steel-wire net in the shape of a fan, hinged from the trawler's cutwater and supported from pulleys at the end of beams shoved out like catheads over the bows. It would be lowered in front of her, below her water-line, to scoop up the mines, or drive them aside. There'd be scores of lives saved, sir."

"So I should think," assented the commander, proceeding with his shaving. "You ought to make a working model of the contrivance and submit it to the authorities. They're almost sure to adopt it, recognising you as a kind of expert on mine-sweeping. And now, there's something else I want to ask you. What has become of Heinrich Hilliger and his son, do you know? I have heard of your raid on the pigeon-loft at Sunnydene, and of the maps and charts that you found, and failed to bring away with you.'

"Max was drowned when the _Atreus_ was mined," Mark explained. "And his father is believed to have gone back to Germany."

"Then whom do you suspect of having taken off the charts and things?" pursued Lieutenant Ingoldsby.

Mark could not explain this mystery. It had puzzled him ever since the night of its occurrence.

"You will be doing a service to your country," said the officer, "if you make a point of finding out exactly where those two are, and what they are doing. For my own part, I don't believe for a moment that Max Hilliger was drowned, or that his father has gone home to Germany. They are alien enemies, you know, and it is not to be wondered at if they are still in England--still even in Haddisport--working their level best to bring about the downfall of Great Britain."

Mark pondered over this recommendation while he was at breakfast in the engine-room, and resolved to make some investigations during his time of leave on shore. He also gave some thought to his invention for picking up explosive mines.

While he was drawing a plan of it, Lieutenant Ingoldsby, again at his post in the conning-tower, called out the command:

"Diving stations!"

The H29 was once more submerged. There was a cloud of smoke on the horizon which might be from the funnels of an enemy cruiser. Seen afterwards in the periscope mirror, however, the stranger turned out to be a British liner. The ballast tanks were blown out, and the submarine rose awash. The electric motor had stopped and the petrol engine had not yet been set in motion. Instead of the telegraph signifying "go ahead!" there came an ominous rasping sound from the neighbourhood of the forward torpedo-chamber. Something was wrong!

"Sounds as if we'd fouled some wreckage," conjectured the chief engineer, standing by his cranks and levers with his eye on the dial.

Mark Redisham was astonished to hear his name called from the conning-tower. He followed three of the men who also had been summoned. When he came out into the open air he discovered Mr. Ingoldsby and Mr. Desmond standing together looking forward along the narrow strip of deck to where a great round shape lay jammed between the hydroplane and its guard.

"It's a German mine!" cried Mark. "Don't let it be moved, sir. Wait! Keep the engines stopped! You've fouled its mooring; but it won't go off--it won't explode--unless one of the horns gets broken or bent."

"That's what I judged," nodded Lieutenant Ingoldsby, looking very grim. "But how is the thing to be cleared away if we don't move it? You know the tricks of these things. What do you advise?"

"Wait a bit, sir," urged Mark. He stooped and quickly took off his boots and stockings. "Let me go along and have a close look at it."

"No, I can't let you," objected the commander. "It's too dangerous."

"Then let one of the men come with me, sir," Mark suggested, not at all alarmed.

Before he could be stopped, he had slipped past the men and was making his way along the wet and slippery platform. Mr. Desmond, also in bare feet, went after him. They reached the place where the mine was lodged. The horns of the deadly machine were fortunately all pointed outward. The mooring line of flexible wire rope had been caught as the submarine rose to the surface and was securely fixed in the hydroplane bearings, held by its own weight and the weight of the sinker.

Mark went down on his hands and knees and examined the thing most carefully, seeing exactly how it was held, calculating how it would fall when released, estimating how it would be kept in position while the mooring-line was being severed. All his scout-craft was exercised. He looked round at the sub-lieutenant.

"We shall manage all right, sir," he declared calmly. "We want a couple of hammocks to pack round the base of the mine for a fender, a strong man with a crowbar to hold it from slipping, while another with a sharp file and a pair of pliers cuts through the mooring warp. When it's cut, you submerge the ship a couple of feet, let go, and the mine will float off. Then the gunner can fire at it and explode it. Do you understand, sir? Excuse my making these suggestions; but I've had a lot to do with handling explosive contact-mines during the last week."

His directions were followed in every detail. In half an hour the work was done without mishap, and the submarine and her crew were saved. The mine, released from its sinker, floated with its rounded top and horns above the surface. The ship stood off, her fourteen-pounder quick-firing gun was raised from its chamber, and the gunner's skill brought about the explosion.

Late in the afternoon of that same day the H29 appeared abreast of Alderwick Knoll. Darby Catchpole saw her from the cliff. Watching her through his telescope, he made out that the flag flying from her mast bore the sign of the skull and crossbones, and by this he knew that she had been in action and had come out victorious.

*CHAPTER X.*

*DARBY CATCHPOLE'S DISCOVERY.*

"I expect she has been putting a torpedo into some German mine-layer," said Darby, speaking to Constable Challis, who stood beside him. "It's the H29."

"Ah!" nodded Constable Challis, "that's the submarine that Lieutenant Ingoldsby's in command of, isn't it? I wish I'd known when I saw his aunt, Mrs. Daplin-Gennery, along the parade just now."

Turning to see if that lady were still in sight, he saluted an elderly gentleman who was hobbling past with the aid of two sticks and with a folded newspaper under one arm.

"Good-evenin', Mr. Croucher," he said. "Any news in the evenin' newspaper, sir?"

"Worse and worse," responded Mr. Croucher, coming to a stop. "Liege has fallen. It will be Namur next, and then Paris. France hasn't a chance. Neither has Russia." He gazed searchingly across the sea. "And then, if the enemy's ships slip out from the Kiel Canal, we're doomed."

"You think so, sir?" questioned Challis, easing the collar of his tunic as if it choked him.

"Think so?" cried Mr. Croucher almost resentfully. "I know! There is nothing more certain. Don't you make any mistake, constable. We've lived long enough in a fool's paradise. I tell you, the Germans have been preparing for this for years and years, only awaiting their chance. And they've got it, now. Nothing can stop them--nothing! Look how they're sweeping through Belgium! Those siege guns of theirs are simply awful. No fortress can resist them, and their naval guns are even greater. What our people have been thinking of over here I don't know. They don't seem to realise our danger. Why, we've no home army worth speaking of, now that the only soldiers we had have gone over to France, leaving us defenceless. We're at the enemy's mercy, Challis."

Constable Challis glanced aside at Darby Catchpole, who was closing his telescope, the submarine having passed beyond sight.

"And how could we hope to prevent their landing on an open coast like this?" pursued Mr. Croucher, bending forward on the support of his two sticks. "I tell you, if their ships break through the cordon of our fleet, we're doomed."

"Indeed, sir?" said Challis with composure. "I wasn't reckonin' on the Germans comin' over here to Haddisport, sir. How will they land their cavalry and artillery through shoal water? They can't bring transport liners across Alderwick Sands."

"Liners?" repeated Mr. Croucher. "Who spoke of liners? They've got hundreds and thousands of flat-bottomed barges lying in the shallows behind the Frisian Islands, ready to be filled with troops and towed over here and beached. They don't need any liners."

Darby Catchpole here ventured to intervene. "And are our Dreadnoughts and cruisers going to hang back while the enemy troops are crossing, sir?" he inquired. "Won't our submarines have a chance?"

"Strictly between ourselves," observed Constable Challis, "I don't believe that a single German soldier will ever set foot in England, except as a prisoner of war."

"Nonsense, Challis, nonsense!" retorted Mr. Croucher. "I've no patience with such childish hopefulness. We're at war against the greatest army the world has ever known, and we're not prepared for it. The Germans will treat us just as they are now treating the Belgians. We've got no army capable of facing them. Even our navy is weaker than it ought to be. The Germans have their Dreadnoughts as well as we, and quite as powerful. They've got crowds of them, and----"

"Not like the _Iron Duke_," Challis interrupted. "Not like the _Queen Elizabeth_ or the _Lion_. What about our 13.5 and 15-inch guns, sir?"

"Our guns are not much good against explosive mines and submarines," rejoined Mr. Croucher. "Look what the enemy have done already with their mines! Catchpole, here, can tell you about the loss of the _Atreus_. And now one of their submarines has sunk another cruiser--the _Pathfinder_. Didn't you read about it in the paper? They've got their spies everywhere, too. They know what we're doing as well as we know it ourselves! Spies, Challis? Why----" He lowered his voice as he glanced along the cliff to the turrets and gables of Sunnydene. "I've been watching that house," he went on, mysteriously. "It's supposed to be empty. No postman goes there, no trade-carts stop at the gate, no gardener looks after the grounds. And yet, only yesterday there was smoke from one of the chimneys--puffs of white smoke, long and short. What was the meaning of it? Signals, Challis, signals!"

"Was there any ship passing, to take up the message, sir?" questioned Darby Catchpole.

Mr. Croucher looked at the boy severely.

"Do you think they'd make signals to seagulls?" he asked. "Of course, there were ships--plenty of them--tramps, coasting schooners, fishing boats. Any one of them might take a message over to Heligoland, telling secrets about the movements of our warships. The house is a perfect nest of spies, in the pay of the enemy. It's all very well for them to pretend to have gone away to Germany. But they haven't. Depend upon it they're living in some subterranean chamber, where they've stored arms and munitions of war, lying low there to join the enemy troops when they come over to murder us all. I tell you, we're doomed, Challis--doomed!"

"Strictly between ourselves," said Constable Challis, when the old man had gone beyond hearing, "I'm not so sure he isn't right about Sunnydene. Mrs. Daplin-Gennery declares she's seen Herr Hilliger prowlin' around at night, likewise his son, Max, who's supposed to be drowned. And young Mark Redisham, who's a Sea Scout like yourself, has found out a thing or two in the pigeon-loft. Strictly between ourselves, I may tell you that we made a raid on the place a few nights ago. Somebody had been there in front of us, however, and cleared everything suspicious away. You may take it from me, as that somebody was either Herr Hilliger or his son."

Darby could have said something concerning his own suspicions of a message sent by pigeon post; but he knew that Constable Challis was a gossip, and he held his own counsel. Nevertheless, he thought it in some way his duty as a Sea Scout to keep an eye upon Sunnydene, and he seldom passed the house without glancing up at the windows and the chimneys to see if there were any sign of habitation.

He was beginning to be assured in his belief that there was no real foundation for further suspicion, when, returning one moonlight night along the cliff from the Alderwick Coastguard Station, he saw something which renewed all his doubts.

During his absence, several tramps and coasters had anchored for the night in the roads; for the coastwise navigation lights were not now lighted to guide ships on their way, and general traffic on the sea ceased after dusk.

Amongst other vessels lying in the fairway inside of Alderwick Knoll, one in particular attracted his notice. It was a foreign-looking ketch. The moon was not high, and he could see the vessel plainly outlined against the track of light across the waves.

At night time, one ketch-rigged boat is very much like another; but there was something in the angle of her bowsprit, in the rake of her two masts, as well as in the clumsy lines of her hull which made him almost certain that she was the _Thor_--the same Dutchman in which Max Hilliger had sailed for Germany hardly more than a fortnight ago. Furthermore, she was anchored in precisely the same spot as on the earlier occasion, directly opposite Sunnydene, and visible from any one of the many front windows. Her riding-light was hung low on her foremast, and there was a second light abaft her mizzen.

Having no pressing need to get home to his supper, Darby lingered, anxious to make certain of the identity of the ketch. He could get into the town as easily by walking along the beach as going by the cliff path or the main road.

For some minutes he stood by the side of a tall gorse bush. Nothing happened. But at length as he watched, the vessel's stern light went out, then reappeared and continued to go in and out with curious regularity.

A person ignorant of the Morse code might have believed that a message was being flashed; but Darby Catchpole knew that it was only that one of the crew was pacing the deck and passing to and fro in front of the lantern.

While he waited in the silence, however, he heard the unmistakable sound of a boat's keel crunching on the shingle. He turned and glanced back at Sunnydene. Only the roof and towers could be seen over the edge of the cliff; but from a small window in the east gable there came a quick flash of light. Was it a signal?

Darby crept upwards a few feet and watched for a repetition of the flash. How long he waited he did not know; but when he stepped back three or four paces he again saw the light and almost laughed aloud when he discovered that it was no more than a reflection of the moon in the glass. Yet it had seemed to move. He was not sure even now that it was not a signal to the ketch.