“That wake was swirling up so strong when we struck it that it was plain the submarine was still only on the way down, and it was no surprise when, a few seconds later, the distinct form of it was visible, close aboard under the starboard side of the bridge.
“I don’t mean that it was distinct in the sense that you could see details such as the bow or stern rudders, or even the conning-tower, but only that a moving cigar-shaped blob of darker green could be plainly made out. The for’ard end was rather more sharply defined than the after, probably because the swirl from the propellers made uneven refraction about the tail. It was doubtless a good deal deeper than it looked, and the fact that it
could be seen at all must have been almost entirely due to the fact that the absence of wind left the surface quite unrippled.
“The appearance of the submarine abreast the bridge was our cue to get busy, and I won’t need to tell you that we went to it good and plenty. We were primed for just that kind of an emergency, and we slapped down a barrage in a way that looked more like chucking coppers for kids to scramble after than the really scientific planting of high explosives that it was. For a minute or two the little old Sherill, dancing down the up-tossed peaks of the explosions, jolted along like the canoe you are dragging over a ‘corduroyed’ portage. Then the going grew smooth again, and under a hard-over right rudder we turned back rejoicing to gather in the sheaves. Yes, it looked quite as simple as harvesting on the old home farm, and it didn’t seem that there could be anything left to do but to go back and pick up with the rake what the mower had brought low. And so it would have been on an ordinary occasion, which, unluckily, this was not. From the first to last, indeed, it was quite the contrary.
“The whole map of that little opening brush was spread out before us as we came back, and almost as clearly, for the moment, as though modelled in coloured clay. The Sherill’s wake, though it had obliterated that of the submarine, coincided with the tell-tale swirl of the latter we had followed,
while the round patches of spreading foam made the dizzily dancing buoys temporarily superfluous as markers of the spots where the depth-charges had exploded. Like every other story that is writ in water, this one was rapidly dissolving; but, from all that we needed to learn from it, the record was as complete as a bronze relief.
“That there was to be another chapter to the story became evident before we had doubled back half the length of that part of the wake we had sprinkled with ‘cans.’ At about the point where two-thirds of that sheaf of depth-charges had been expended a clearly defined wake of oil and bubbles turned sharply off to the left. The presence of that little trail cleared up several important points right then and there without following it any farther, though I will hardly need to tell you that we didn’t drop anchor to hold a court of inquiry over it. The vital thing it told us was that—strange as it seemed—our under-water bombardment had not sent the U-boat to the bottom, nor even injured it sufficiently to compel it to come to the surface. But that it was injured, and probably fairly badly, was proved by the wake of oil and bubbles. Don’t ever let any one delude you with that yarn about the way Fritz sends up oil and bubbles to baffle pursuit. There may be circumstances under which he could work that particular brand of foxiness with profit, but if there is one place where you could be sure he would
not try anything of that kind on, it is when a destroyer has got his nose on his trail, with her eye and ears a-cock for just that kind of little first-aid to ‘can-dropping.’ For a submarine voluntarily to release air or oil when a destroyer is ramping round overhead would be just about like a burglar scattering a trail of confetti to baffle the pursuit of the police. Fritz is as full of ways that are dark and of tricks that are vain as Ah Sin, but—with the hounds at his heels—nothing so foolish as that oil and bubble stunt of popular fiction.
“The first few of the ‘cans’ had evidently burst near enough to this Fritz to buckle his shell and release the oil and air, but his sharp right-angled turn to the left had taken him quite clear of the last of the charges, which had only been thrown away. Wounded and winged as he appeared to be, the next thing in order was to polish him off. Slowing down slightly, the captain steadied the Sherill on the wake.
“As we passed the point where this was rising, the rate at which it was extended gave the approximate speed of the U-boat, and the fact that this was not above three knots seemed only another indication that all was not well with him. Holding on past the ‘bubble fount,’ we passed over the point below which the U-boat must have been moving, but now he was so much more deeply submerged than before that no hint of his outline was visible on either side. We knew he was there, however, and