It was close on one o'clock when the "wirelessing" terminated. U75, which had hitherto been running awash, was now trimmed for surface work.
Most of the crew went on deck. Amongst them were Ross and Vernon, no one offering any objection.
The sea was no longer rough. A long oily swell took the place of the white-crested wave. The night was dark. Only a few stars were visible. Away to the S.E., the black outlines of the Cornish coast reared themselves like an enormous wall against the gloomy sky.
Suddenly Vernon touched his chum's elbow, as a faint pin-prick of light glimmered twice. It was the shore agent's signal that the coast was clear.
Barely carrying steerage-way, U75 stood in towards the as yet invisible Port Treherne. Already her crew had brought the collapsible canvas boat from below, "man-handling" it through the fore hatch. The men, having opened it out and shipped the felt-lined and well-greased rowlocks, stood by to launch it.
Gradually the towering cliffs enclosing the creek became distinguishable against the loftier background of gaunt hills. Into the gap the submarine crept with the utmost caution, until it seemed as if she were on the point of running her nose against the sheer face of the granite wall. The water bubbled slightly as her motors were reversed; then, turning in her own length, she brought up, with her bows pointing seawards.
Three of the crew grasped the canvas boat and pushed it gently into the water on the port side. One of them clambered in and shipped the oars in the row-locks.
The two lads were cautiously scanning the shores of the inlet. Ross could sniff the unmistakable Cornish air. The call of home seemed irresistible. It looked a comparatively easy matter to slip quietly over the starboard side, and swim with noiseless strokes towards the weed-covered rocks that showed six feet or more above the sea. It was half ebb-tide; there was little or no drift out of the cove. Under the shadow of those dark cliffs detection seemed almost impossible, unless the submarine went to the risky expedient of switching on her search-light.
They moved stealthily towards the light wire railing on the starboard side just abaft the conning-tower. Everything seemed in their favour. Kapitan Schwalbe and the Unter-leutnant were on the navigation platform, peering through their night-glasses towards the flat rock that served as a landing-place. Two of the seamen were engaged in coiling down a hand-lead line; the rest of the men on deck were devoting their attention to the now departing canvas boat.
"Not so fast, my friends," exclaimed a low deep voice, which the lads recognized as that of Kapitan Schwalbe. "Remember I have a pistol ready to hand."
"How in the name of goodness did he know what we were up to?" thought Ross.
The chums stood stock-still. They felt much like children found out in some petty escapade.
"Koppe! Where are you?" asked the Kapitan in a loud whisper.
"Here, sir," replied the seaman.
"I hold you responsible for these Englishmen. Now they are trying to give us the slip. Take them below. But hold on. Secure them to a stanchion. Chain them up, and bring me the key."
The seaman approached the lads almost apologetically, and led them to the port side just for'ard of the conning-tower. A light steel chain was hitched round Ross's right ankle and Vernon's left, and deftly padlocked round one of the uprights supporting the hand-rail.
"It is of no use trying any of your pranks here," commented Kapitan Schwalbe, still in a low tone. "You are only looking for trouble."
For several moments all was still, save for the screech of a benighted gull. Overhead a meteor passed swiftly across the sky, throwing a pale gleam upon-the lurking submarine.
"Wer da?"
The words, although uttered in an undertone, travelled distinctly over the placid waters of the cove.
The sailor in the boat muttered some inaudible reply. The listeners in the submarine could detect the sound of his oars as he laid them across the thwarts. Then, after further conversation, could be heard the rumble of metal as the tins of petrol were rapidly placed in the boat.
"How many are there?" asked Kapitan Schwalbe eagerly as the men returned with the first load.
"Forty here, Herr Kapitan. Altogether there are over two hundred."
"Then be sharp and whip them on board. Was there any communication for me?"
"A bundle of English newspapers, sir, and this letter."
The man drew the documents from the inside of his jumper and passed them to a seaman, who in turn handed them to the skipper.
"I may have to land, sir," continued the seaman. "The rest of the cans are in a cove at some distance from the landing-place. Can Max go with me to mind the boat? There is a slight ground-swell at times, and she might have a hole through her canvas if she is allowed to grind against the rocks."
Receiving an affirmative reply, the man told his comrade to get on board, and once more the boat vanished into the darkness.