The big seaplane circled low over the harbour and then headed seaward, climbing slowly. There were two men aboard—a young Sub-Lieutenant as pilot and Mottin as observer. Mottin sat crouched low and leaning forward as he studied the chart-holder before him and scratched times and notes in his log-book. They were off on a routine patrol, but there was the additional interest to the trip that on "information received" they were to pay a little more attention than usual to a particular locality.
From his seat Mottin could see nothing of the pilot but his head and shoulders—a back view only, and that obscured by swathings of leather and wool. The two men's heads were joined by a cumbersome arrangement of listeners and tubes which, theoretically, made conversation practicable. As a matter of fact, the invariable rule of repeating every observation twice, and of adding embroidery to each repetition, pointed to a discrepancy between the theory and practice of the instrument. The machine was a big one, and its engines were in proportion. The accommodation in the broad fuselage was considerable, but on the present trip the missing units of the crew were accounted for by an equal weight of extra petrol and T.N.T. "eggs."
The morning had been hazy and they had delayed their start till nearly noon. It was not as clear as it might be even then, for in a quarter of an hour from leaving the slip the land was out of sight astern. At a thousand feet the pilot levelled off and ceased to climb. He flew mechanically, his head bent down to stare at the compass-card. At times he fiddled with air and throttle, twisting his head to watch the revolution indicator. The occasional bumping and rocking of the machine he corrected automatically without looking up. He had long ago arrived at the state of airmanship which makes a pilot into a sensitive inclinometer, acting every way at once.
Mottin finished his scribbling and sat up to look round. He raised himself till he sat on the back of his seat, and began to sweep the sea and horizon with a pair of large-field glasses. The wind roared past him, pressing his arm to his side as he faced to one side or the other, and making him strain the heavy glasses close to his eyes to keep them steady. An hour after starting he touched the pilot on the shoulder and shouted into his own transmitter. He waited a few seconds and shouted again, with the conventional oath to drive the sound along. The pilot nodded his swathed and helmeted head and swung the machine round to a new course. Mottin crouched down again and began to study his chart afresh. Navigation was easy so long as the weather was clear, but with poor visibility, which might get worse instead of better, he knew that it was remarkably easy to get lost in the North Sea, and at this moment he wanted to see his landfall particularly clearly. Five minutes later he saw it, and signalled a new course to the pilot by a nudge and a jerk of his gloved hand. A low dark line had appeared on the starboard bow, a line with tall spires and chimneys standing up from it at close intervals. The seaplane banked a little as they turned and headed away, leaving the land to recede and fade on their quarter. The hazy sun was low in the west and the mist was clearing. It had been none too warm throughout the journey, but it was now distinctly cold, the chill of a winter evening striking through fur and leather as if their clothes had been slit and punctured in half a dozen places.
Mottin had just slid back in his seat after a sweeping search of the sea through his glasses, and was slowly winding, with cold fur-gloved fingers, the neat carriage clock on the sloping board before him, when he heard a yelping war-cry from the pilot and felt the machine dive steeply and swerve to port. He half rose in his seat and then slipped back to feel for his bomb-levers. The submarine was just breaking surface eight hundred feet below and a mile ahead. As he looked she tucked down her bow and slipped under again, having barely shown her conning-tower clear of the short choppy waves. The pilot throttled well down and glided over the smooth, ringed spot which marked where she had vanished. As it slid past below them he opened up his engines again and "zoomed" back to his height. He turned his head to look at Mottin, but said nothing. Mottin made a circular motion with his hand and they began a wide sweep round, climbing all the while. Mottin sat back and thought hard. No, it had not been indecision that had prevented him from dropping bombs then. He knew it was not that, but the exact reasons which had flashed through his mind at the fateful moment must be hunted out and marshalled again. He knew that his second self, his wide-awake and infallible substitute who took over command of his body in moments of emergency, had thought it all out in a flash and had arrived at his decision for sound reasons. Yes, it was clear now, but that confounded fighting substitute of his was just a bit cold-blooded, he thought. They had petrol for the run home with perhaps half an hour to spare. Fritz had not seen them, as his lid had not opened—or at any rate if he had seen them through his periscope, the fact of no bomb having been dropped would encourage him to think that the seaplane had passed on unknowing. Of course they might have let go bombs, but, well, Fritz must have been at anything down to 80 feet at the moment they passed over him, and it was chancy shooting. Yes, it was quite clear. Fritz should be up again in an hour (he evidently wanted to come up), and if they were only high up and ready they would get a fair chance at him. Of course, they would not get home if they waited an hour; but if that cold-blooded second self of his thought it the right thing and a proper chance to take, well, it was so. Mottin looked over the side and wished it was not so loppy. A long easy swell was nothing, but this short choppy sea was going to be the devil. The pilot shouted something to him and pointed at the clock and the big petrol tank overhead. Mottin nodded comprehension, and shouted back. The Sub took a careful look overside and studied the water a moment. Then he laughed back at Mottin, and shouted something about bathing, which was presumably facetious, but which was lost in the recesses of the headpieces.
The sun was down on the horizon, and the hour had grown to a full ninety minutes before the chance came. They had not worried about clocks or thoughts of petrol after the first half-hour of circling. They were "for it," anyhow, after that, and it was going to come in the dark too, so that the question of whether it was going to be fifty or a hundred miles from land did not make much difference. Almost directly below them the long grey hull rose and grew clear, the splashing waves making a wide area of white water show on each side of her. The seaplane's engines stopped with startling suddenness, and to the sound of a rushing wind in the wires and of ticking, swishing propellers they began a two-thousand-feet spiral glide, coming from as nearly overhead as the turning circle of the big machine would allow. At two hundred feet the pilot eased his rudder and began a wider turn, and then the German captain saw. He leapt for the conning-tower, leaving a startled look-out man behind. The man tried to follow him down, but the lid slammed before he could arrive at it. He turned and looked helplessly at the big planes and body rushing down a hundred yards astern. With his hands half raised and shoulders hunched up the poor devil met his death, two huge bombs "straddling" the conning-tower and bursting fairly on the hull as the boat started under. Mottin had a vision of a glare of light from the rent hull, a great rush of foaming, spouting air, and then a graceful knife-edge stem, with the bulge of torpedo-tubes on each side of it, just showed and vanished in the turmoil of broken water. The seaplane roared up again, heading west, the young pilot—apparently oblivious to the fact that he hardly expected to be alive till morning—displaying his feelings on the subject of his late enemy by a series of violent "switchbacks."
Mottin checked him, rose, and began a careful look round. Any ship would be welcome now, neutral or not; but this was an unfrequented area to hope to be picked up in. The petrol might last five minutes or half an hour—one could not be certain. The gauge was hardly accurate enough in this old bus to work by. As he looked the engines gave a premonitory splutter and then picked up again. Well, it was five minutes, he reflected, not half an hour—that was all. The pilot turned and headed up wind. With the engines missing more and more frequently they glided down, making a perfect landing of the "intentional pancake" order on the crest of a white-topped four-foot wave. Instantly they began to feel the seas—the hard, rough, senseless water that was so different to the air they had come from. The machine made wicked weather of it, and it was obvious that she could hardly last long. She lurched and rocked viciously, constraining them to cling to the sides of the frail body. Mottin pulled off his headpiece, and the pilot followed suit.
"Well," said Mottin, "it was worth it—eh?"
"By gum, yes! It was that, and I give you full numbers, sir. I thought for a moment you had taken too long a chance, but you were right."
A wave splashed heavily over the speaker and laid three inches of water in a pool around his ankles.