His voice rose a little. Scarlett, who was on the look-out, had crept along the deck and touched Bernard on the shoulder.

"Come forrard, sir, if you please," the man said in a hoa.r.s.e whisper. He could hardly get the words out, and at first I thought his teeth were chattering with cold, but it was not so.

We crept to the bows of the Hulk and peered over the broken, rotting taffrail. Two feet below was the beam of the signal lamp shining up the creek towards the sea. The snow had temporarily stopped in this part of the marsh and the moon was bright. Thirty Main stretched away ahead as far as we could see, two hundred yards long and a hundred wide, of black, gleaming steel. The tide was full at flood.

Scarlett handed my brother a pair of night-gla.s.ses. Bernard gazed through them for twenty seconds, and then they fell softly on the deck.

"Oh G.o.d!" he said in a low voice, "so it is _that_, and I never thought of it before! Fool! Fool!"

I stared out also, not daring to say a word. No man can see better at night than I. What _was_ that? Something slowly floating down the centre of the creek, a black, oblong patch. Was it two or three duck swimming landwards with the tide?

Then the black patch lifted itself from the water. It seemed to have a long, narrow tail--the whole thing was curiously distinct in the moonlight. In a second I realised that something was _being pushed up from below_. I had never seen anything like it before. I experienced that hideous sensation in the pit of the stomach that comes to people who are face to face with the unknown and the unexpected for the first time in their lives. All this happened in half a minute. The black, oblong thing was now high in the air on the end of a pole which came straight up through the middle of the creek. Something else was rising, a black hump, which grew and grew, until a grey tower stood there;--stood there but moved slowly towards us--or did it begin to recede?

I heard Bernard"s voice: "Stand by the lamp!"

"Aye, aye, sir!"

Scarlett was bending low over the bows of the Hulk. In the middle of the waterway something long and lean was showing. There was a soft, metallic clang, and then, from the centre of the dark, floating object, a light flashed quickly, three times. Immediately I heard the click of the shutter of our own lamp and saw the occulting beam below flash and disappear in answer.

I knew, I think in some subconscious way, I must have known from the very first. The whole thing, in its magnificent and unsuspected daring, its malevolent simplicity, struck me like a blow. This was a German submarine; this was the channel by which the Master-Spy, von Vedal, and his agents had been sending information to the enemy! On my own quiet marshes, in Thirty Main Creek!

"One of their "D" cla.s.s, sir; same as our "E." Crew of fifteen, no quick-firing gun, and probably wireless. Handy little craft, sir!"

"They"ll be coming aboard in a minute, Scarlett."

"Aye, aye, sir. If you look, sir, you"ll see they are getting one of those collapsible boats up. New thing, sir, and very handy. Holds six.

Ah!"

I could see quiet and purposeful activity round the conning-tower of the submarine. A group of dark figures was silhouetted in the moonlight, and presently a little boat, like a bobbing cork, lay by her side.

Three men got into it and it pushed off. It went towards the other side of Thirty Main.

"Concealed moorings, sir," Scarlett whispered. "They"ve been here before. It"s dead water, and the ship"d drift, if ..."

I heard no more. I watched breathlessly. The boat went to the far side of the creek and remained there for nearly two minutes. If there was a cable, I did not see it, but presently the boat turned and came rapidly towards the Hulk.

"John, take him quietly to the cabin and shove him in--it"s the Commander coming aboard," my brother added. "Scarlett, get back into the deck-house and light that lamp. Mr. Carey is dressed like the German boatswain, and he will show the officer straight into the deck-house.

It"s ten to one the sailors won"t come up. Remember to do your job without the slightest noise--you, Adams, and Bosustow."

"Out him, sir?"

"I"m afraid so. There is no other way. Directly it is over, take off his clothes and bring them down into the cabin. Mind the men in the boat hear nothing."

"Aye, aye, sir."

Then my brother turned to me. The boat was now almost by the side of the Hulk.

"You understand, John?" he said.

I touched his arm, afraid to speak.

"Then go and get the rope-ladder."

I stepped to the deck-cabin and saw the three sailors standing round it among the litter of shooting gear. A smoky lamp hung from the ceiling.

Scarlett pa.s.sed me the ladder. I took it and went to the side--my brother had disappeared.

There was a low hiss seven feet below. I hissed, too, fixed the ladder hooks, and dropped the rest of it. One of the sailors caught it, while the other steadied the boat, and a slim man of just over middle height came up like a cat. He wore some sort of dark uniform, what it was I could not see. The collar was turned up round his face, which appeared to be clean-shaved.

I saluted and stepped towards the deck-house. He followed me without a sound.

Then I tapped on the door, which opened immediately, and as it did so I shot him in with a smart blow between the shoulder-blades. There was just one little gasping sound, and that was all. The door closed gently.

The two sailors below in the boat sat quietly enough. I went down into the saloon.

Quick as I was, my brother was before me. He was talking earnestly to Doris in a low voice. I stood at the door at attention, and I think I never saw a stranger scene.

Old Lieutenant Murphy, in uniform, was seated at the table. His nostrils were opening and shutting in his tanned face. He was exactly like an old dog brought to the hunt for the last time. The door into the galley was half open. d.i.c.kson major stood there with a magazine pistol in his hand.

d.i.c.kson max. sat opposite the lieutenant, his face a mask of determination and strength. It was wonderful.

"You quite understand, Doris? You can be brave?"

"I quite understand, Bernard."

"Then we will wait a minute. Sit down, John."

We all sat down--waiting. One minute--two minutes pa.s.sed. Then came a light tap upon the door. It opened and Scarlett entered. His face was rather red, and he breathed heavily. On his right arm he carried a bundle of clothes.

My brother looked at him with a lift of the eyebrows, and Scarlett nodded, placing the clothes on the table.

"Go through these clothes, Lieutenant," Bernard said. Then he turned to Scarlett and whispered.

The man saluted and disappeared. A few seconds after, my brother beckoned to Doris.

"Now, then," he said, "be brave!"--and then, turning to me, "Stand out of sight on deck, John, and be ready to help."

We crept up on deck. To my unutterable surprise, Doris went to the side and leant over. She spoke in German and in a very low voice.

"She"s telling them that they"re to come up on board and have a drink,"

my brother said.

The two figures below rose with alacrity. The first one ascended the ladder as Doris whipped down the hatchway into the cabin. The second sailor followed his companion.

I was not called upon to help, thank Heaven! Scarlett, Adams, and Bosustow rose from nowhere.

"That accounts for three," said my brother, but I turned my head away not to see what was going on.

When we were again down in the cabin I was shaking like a leaf.

"Drink this," Bernard said sternly, "and pull yourself together. It is War, don"t you understand that, man?"