The Wabbler went westward, with a dozen of its fellows, by night and in the belly of a sleek, swift-flying thing. There were no lights anywhere save the stars overhead. There was a sustained, furious roaring noise, which was the sound the sleek thing made in flying. The Wabbler lay in its place, with its ten-foot tail coiled neatly above its lower end, and waited with a sort of deadly patience for the accomplishment of its destiny. It and all its brothers were pear-shaped, with absurdly huge and blunt-ended horns, and with small round holes where eyes might have been, and shielded vents where they might have had mouths. The looked chinless, somehow. They also looked alive, and inhuman, and filled with a sort of passionless hate. They seemed like bodiless demons out of some metallic hell. It was not possible to feel any affection for them. Even the men who handled them felt only a soft of vengeful hope in their capacities.

The Wabblers squatted in their racks for long hours. It was very cold, but they gave no sign. The sleek, swift-flying thing roared on and roared on. The Wabblers waited. Men moved somewhere in the flying thing, but they did not come where the Wabblers were until the very end. But somehow, when a man came and inspected each one of them very carefully and poked experimentally about the bottoms of the racks in which the Wabblers lay, they knew that the time had come.

The man went away. The sleek thing tilted a little. It seemed to climb. The air grew colder, but the Wabblers—all of them— were indifferent. Air was not their element. Then, when it was very, very cold indeed, the roaring noise of the flying thing ceased abruptly. The cessation of the noise was startling. Presently little whistling, whispering noises took the place of the roar, as hearing adjusted to a new level of sound. That whistling and whining noise was wind, flowing past the wings of the flying thing. Presently the air was a little warmer—but still very cold. The flying thing was gliding, motors off, and descending at a very gradual slant.

The Wabbler was the fourth in the row of its brothers on the port side of the flying thing. It did not stir, of course, but it felt an atmosphere of grim and savage anticipation. It seemed that all the brothers coldly exchanged greetings and farewell. The time had definitely come.

The flying thing leveled out. Levers and rods moved in the darkness of its belly. The feeling of anticipation increased. Then, suddenly, there were only eleven of the Wabblers. Wind roared where the twelfth had been. There were ten. There were nine, eight, seven, six—

The Wabbler hurtled downward through blackness. There were clouds overhead now. In all the world there was no speck of actual light. But below there was a faint luminosity. The Wabbler's tail uncurled and writhed flexibly behind it. Wind screamed past its ungainly form. It went plunging down and down and down, its round holes—which looked so much like eyes—seeming incurious and utterly impassive. The luminosity underneath separated into streaks of bluish glow, which were phosphorescences given off by the curling tips of waves. Off to westward there was a brighter streak of such luminosity. It was surf.

Splash! The Wabbler plunged into the water with a flare of luminescence and a thirty-foot spout of spume and spray rising where it struck. But then that spouting ceased, and the Wabbler was safely under water. It dived swiftly for twenty feet. Perhaps thirty. Then its falling checked. It swung about, and its writhing tail settled down below it. For a little while it seemed almost to intend to swim back to the surface. But bubbles came from the shielded opening which seemed to be a mouth. It hung there in the darkness of the sea—but now and then there were little fiery streaks of light as natives of the ocean swam about it—and then slowly, slowly, slowly it settled downward. Its ten-foot tail seemed to waver a little, as if groping.

Presently it touched. Ooze. Black ooze. Sea bottom. Sixty feet overhead the waves marched to and fro in darkness. Somehow, through the stilly silence, there came a muffled vibration. That was the distant surf, beating upon a shore. The Wabbler hung for an instant with the very tip of its tail barely touching the bottom. Then it made small sounds inside itself. More bubbles came from the round place like a mouth. It settled one foot; two feet; three. Three feet of its tail rested on the soft ooze. It hung, pear-shaped, some seven feet above the ocean bottom, with the very tip of its horns no more than four feet higher yet. There were fifty feet of empty sea above it. This was not its destiny. It waited passionlessly for what was to happen.

There was silence save for the faint vibration from the distant surf. But there was an infinitesimal noise, also, within the Wabbler's bulk, a rhythmic, insistent, hurried tick-tick-tick-tick—It was the Wabbler's brain in action.

Time passed. Above the sea the sleek, swift-flying thing bellowed suddenly far away. It swerved and went roaring back in the direction from which it had come. Its belly was empty now, and somewhere in the heaving sea there were other Wabblers, each one now waiting as the fourth Wabbler did, for the thing that its brain expected. Minutes and minutes passed. The seas marched to and fro. The faraway surf rumbled and roared against the shore. And higher yet, above the clouds, a low-hanging invisible moon dipped down toward a horizon which did not show anywhere. But the Wabbler waited.

The tide came. Here, so far from the pounding surf, the stirring of the lower levels of the sea was slight indeed. But the tide moved in toward the land. Slowly, the pressure of water against one of the Wabbler's sides became evident. The Wabbler leaned infinitesimally toward the shore. Presently the flexible tail ceased to be curved where it lay upon the ooze. It straightened out. There were little bluish glows where it stirred the phosphorescent mud. Then the Wabbler moved. Shoreward. It trailed its tail behind it and left a little glowing track of ghostly light.

Fish swim about it. Once there was a purring sound, and propellers pushed an invisible, floating thing across the surface of the sea. But it was far away and the Wabbler was impassive. The tide flowed. The Wabbler moved in little jerks. Sometimes three feet or four, and sometimes eight or ten. Once, where the sea bottom slanted downward for a space, it moved steadily for almost a hundred yards. It came to rest then, swaying a little. Presently it jerked onward once more. Somewhere an indefinite distance away were its brothers, moving on in the same fashion. The Wabbler went on and on, purposefully, moved by the tide.

Before the tide turned, the Wabbler had moved two miles nearer to the land. But it did not move in a straight line. Its trailing, flexible tail kept in the deepest water and the strongest current. It moved very deliberately and almost always in small jerks, and it followed the current. The current was strongest where it moved toward a harbor entrance. In moving two miles shoreward, the Wabbler also moved more than two miles nearer to a harbor.

There came a time, though, when the tide slackened. The Wabbler ceased to move. For half an hour it hung quite still, swaying a little and progressing not at all, while the tick-tick-tick-tick of its brain measured patience against intent. At the end of the half-hour there were small clanking noises within its body. Its shielded mouth emitted bubbles. It sank, and checked, and gave off more bubbles, and sank again. It eased itself very cautiously and very gently into the ooze. Then it gave off more bubbles and lay at rest.

It waited there, its brain ticking restlessly within it, but with its appearance of eyes impassive. It lay in the darkness like some creature from another world, awaiting a foreordained event.

For hours it lay still with no sign of any activity at all. Toward the end of those hours, a very faint graying of the upper sea became manifest. It was very dim indeed. It was not enough, in all likelihood, for even the Wabbler to detect the slight movement of semi-floating objects along the sea floor, moved by the ebb tide. But there came a time when even such movements ceased. Again the sea was still. It was full ebb. And now the Wabbler stirred.

It clanked gently and wavered where it lay in the ooze. There was a cloud of stirred-up mud, as if it had emitted jets of water from its under parts. It wabbled to one side and the other, straining, and presently its body was free, and a foot or two and then four or five feet of its tail—but it still writhed and wabbled spasmodically—and then suddenly it left the sea floor and floated free.

But only for a moment. Almost immediately its tail swung free, the Wabbler spat out bubbles and descended gently to the bottom again. It rested upon the tip of its tail. It spat more bubbles. One—two—three feet of its tail rested on the mud. It waited. Presently the flood tide moved it again.

It floated always with the current. Once it came to a curve in the deeper channel to which it had found its way, and the tide tended to sweep it up and out beyond the channel. But its tail resisted the attempt. In the end, the Wabbler swam grandly back to the deeper water. The current was stronger there. It went on and on at a magnificent two knots.

But when the current slowed again as the time of the tide change neared, the Wabbler stopped again. It swung above the yard-length of its tail upon the mud. Its brain went tick-tick-tick-tick and it made noises. It dribbled bubbles. It sank, and checked, and dribbled more bubbles, and sank cautiously again—It came cautiously to rest in the mud.

During this time of waiting, the Wabbler heard many sounds. Many times during slack tide, and during ebb tide, too, the water brought humming, purring noises of engines. Once a boat came very near. There was a curious hissing sound in the water. Something—a long line—passed very close overhead. A minesweeper and a minesweep patrolled the sea, striving to detect and uproot submarine mines. But the Wabbler had no anchor cable for the sweep to catch. It lay impassively upon the bottom. But its eyes stared upward with a deadly calm until the minesweeper passed on its way.

Once more during the light hours the Wabbler shook itself free of the bottom ooze and swam on with the tide. And once more—with another wait on the mud while the tide flowed out—at night. But day and night meant little to the Wabbler. Its ticking brain went on tirelessly. It rested, and swam, and swam, and rested, with a machinelike and impassive pertinacity, and always it moved toward places where the tide moved faster and with channels more distinct.

At last it came to a place where the water was no more than forty feet deep, and a distinct greenish-blue light came down from the surface sunshine. In that light the Wabbler was plainly visible. It had acquired a coating of seaweed and slime which seemed to form a sort of aura of wavering greenish tentacles. Its seeming eyes appeared now to be small and snakelike and very wise and venemous. It was still chinless, and its trailing tail made it seem more than ever like some bodiless demon out of a metallic hell. And now it came to a place where for a moment its tail caught in some minor obstruction, and as it tugged at the catch, one of its brothers floated by. It passed within twenty feet of the fourth Wabbler, and they could see each other clearly. But the fourth Wabbler was trapped. It wavered back and forth in the flood tide, trying to pull free, as its fellow swam silently and implacably onward.

Some twenty minutes after that passage there was a colossal explosion somewhere, and after that very many fuzzy, purring noises in the sea. The Wabbler may have known what had happened, or it may not. A submarine net across a harbor entrance is not a thing of which most creatures have knowledge, but it was part of the Wabbler's environment. Its tick-tick-tick-ticking brain may have interpreted the explosion quite correctly as the destiny of its brother encountering that barrier. It is more likely that the brain only noted with relief that the concussion had broken the grip of the obstruction in the mud. The Wabbler went onward in the wake of its fellow. It went sedately, and solemnly, and with a sort of unholy purposefulness, following the tidal current. Presently there was a great net that stretched across the channel, far beyond any distance that the Wabbler could be expected to see. But right where the Wabbler would pass, there was a monstrous gaping hole in that net. Off to one side there was the tail of another Wabbler, shattered away from that other Wabbler's bulk.

The fourth Wabbler went through the hole. It was very simple indeed. Its tail scraped for a moment, and then it was inside the harbor. And then the tick-tick-ticking of the Wabbler's brain was very crisp and incisive indeed, because this was its chance for the accomplishment of its destiny. It listened for sounds of engines, estimating their loudness with an uncanny precision, and within its rounded brainpan it measured things as abstract as variations in the vertical component of terrestrial magnetism. There were many sounds and many variations to note, too, because surface craft swarmed about the scene of a recent violent explosion. Their engines purred and rumbled, and their steel hulls made marked local changes in magnetic force. But none of them came quite close enough to the Wabbler to constitute its destiny.

It went on and on as the flood tide swept in. The harbor was a busy one, with many small craft moving about, and more than once in these daylight hours flying things alighted upon the water and took off again. But it happened that none came sufficiently near. An hour after its entrance into the harbor the Wabbler was in a sort of eddy, in a basin, and it made four slow, hitching circuits about the same spot—during one of which it came near to serried ranks of piling—before the time of slack water. But even here the Wabbler, after swaying a little without making progress for perhaps twenty minutes, made little clanking noises inside itself and dribbled out bubbles and eased itself down in the mud to wait.

It lay there, canted a little and staring up with its small, round, seeming eyes with a look of unimpassioned expectancy. Small boats roved overhead. Once engines rumbled, and a wooden-hulled craft swam on the surface of the water to the very dock whose pilings the Wabbler had seen. Then creaking sounds emanated from those pilings. The Wabbler may have known that unloading cranes were at work. But this was not its destiny either.

There came other sounds of greater import. Clankings of gears. A definite, burning rush of water. It continued and continued. The Wabbler could not possibly be expected to understand, of course, that such burbling underwater sounds are typical of a drydock being filled—the filling beginning near low tide when a great ship is to leave at high. Especially, perhaps, the Wabbler could not be expected to know that a great warship had occupied a vastly important drydock and that its return to active service would restore much power to an enemy fleet. Certainly it could not know that another great warship waited impatiently to be repaired in the same basin. But the restless tick-tick-tick-tick which was the Wabbler's brain was remarkably crisp and incisive.

When flood tide began once more, the Wabbler jetted water and wabbled to and fro until it broke free of the bottom. It hung with a seeming impatience—wreathed in seaweed and coated with greenish slime—above the tail which dangled down to the harbor mud. It looked alive, and inhuman, and chinless, and it looked passionately demoniac, and it looked like something out of a submarine Gehenna. And, presently, when the flood tide began to flow and the eddy about the docks and the dry dock gates began, the Wabbler inched as if purposefully toward the place where the water burbled through flooding valves.

Sounds in the air did not reach the Wabbler. Sounds under water did. It heard the grinding rumble of stream winches, and it heard the screeching sound as the drydock gates swung open. They were huge gates, and they made a considerable eddy of their own. The Wabbler swam to the very center of that eddy and hung there, waiting. Now, for the first time, it seemed excited. It seemed to quiver a little. Once when it seemed that the eddy might bring it to the surface, it bubbled patiently from the vent which appeared to be a mouth. And its brain went tick-tick-tick-tick within it, and inside its brainpan it measured variations in the vertical component of terrestrial magnetism, and among such measurements it noted the effect of small tugs which came near but did not enter the drydock. They only sent lines within, so they could haul the warship out. But the tugs were not the Wabbler's destiny either.

It heard their propellers thrashing, and they made, to be sure, a very fine noise. But the Wabbler quivered with eagerness as somewhere within itself it noted a vast variation in the vertical magnetic component, which increased and increased steadily. That was the warship moving very slowly out of its place in the drydock. It moved very slowly but very directly toward the Wabbler, and the Wabbler knew that its destiny was near.

Somewhere very far away there was the dull, racking sound of an explosion. The Wabbler may have realized that another of its brothers had achieved its destiny, but paid no heed. Its own destiny approached. The steel prow of the battleship drew nearer, and then the bow plates were overhead, and something made a tiny click inside the Wabbler. Destiny was certain now.

It waited, quivering. The mass of steel within the range of its senses grew greater and greater. The strain of restraint grew more intense. The tick-tick-ticking of the Wabbler's brain seemed to accelerate to a frantic—to an intolerable—pace. And then—

The Wabbler achieved its destiny. It turned into a flaming ball of incandescent gases—three hundred pounds of detonated high explosive—squarely under the keel of a thirty-five thousand-ton battleship which at the moment was only halfway out of a drydock. The water-tight doors of the battleship were open, and its auxiliary power was off, so they could not be closed. There was much need for this drydock, and repairs were not completed in it. But it was the Wabbler's destiny to end all that. In three minutes the battleship was lying crazily on the harbor bottom, half in and half out of the drydock. She careened as she sank, and her masts and fighting tops demolished sheds by the drydock walls. Battleship and dock alike were out of action for the duration of the war.

And the Wabbler—

A long, long time afterward—years afterward—salvage divers finished cutting up the sunken warship for scrap. The last irregularly cut mass of metal went up on the salvage slings. The last diver down went stumbling about the muddy harbor water. His heavy, weighted shoes kicked up something. He fumbled to see if anything remained to be salvaged. He found a ten-foot, still-flexible tail of metal. The rest of the Wabbler had ceased to exist. Chronometer, tide-time gear, valves, compressed-air tanks, and all the balance of its intricate innards had been blown to atoms when the Wabbler achieved its destiny. Only the flexible metal tail remained intact.

The salvage diver considered that it was not worth sending the sling down for again. He dropped it in the mud and jerked on the lifeline to be hauled up to the surface.