Sallorsen turned his head and followed the torpooner's intent, amazed gaze.

Ken said:

"There's proof of their intelligence! I've been watching—didn't realize at first. Look, here it comes!"

Several sealmen, while Sallorsen had been talking, had come dropping down from the main mass of the horde, and had grouped around the abandoned torpoon which lay some feet ahead of the submarine's bow. Expertly they had loosened the seaweed-ropes which bound it to the sea-floor, then slid back, watching alertly, as if expecting the torpoon to speed away of its own accord. Its batteries, of course, had worn out weeks before, so the steel shell did net budge. The sealmen came down close to it again, and lifted it.

They lifted it easily with their prehensile flipper-arms, and with maneuvering of delicate sureness guided it through the gash in the Peary's bow. Inside, they hesitated with it, midway between deck and ceiling of the flooded compartment. They poised for perhaps a full minute, judging the distance, while the two men stared; and then quickly their powerful tail flippers lashed out and the torpoon jumped ahead. It sped straight through the water, to crash its tough nose of steel squarely into the quarsteel pane of the watertight door, then rebounded, and fell to the deck.

"My God!" gasped Sallorsen. But Ken wasted no words then. He pressed closer to the quarsteel and examined it minutely. The substance showed no visible effect, but the action of the sealmen destroyed whatever hope he had felt.

The sealmen had swerved aside at the last minute; and now, picking up the torpoon again and guiding it back to the other end of the compartment, they hurled it once more with a resounding crash into the quarsteel pane.

"How long will it last under that?" Ken asked tersely.

Obviously, Sallorsen's wits were muddled at this turn. He remained gaping at the creatures and at the torpoon, now turned against its mother submarine. Ken repeated the question.

"How long? Who knows? It's as strong as steel, but—there's the pressure—and those blows hit one spot. Not—long."

Capping his words, there re-echoed again the loud crash of the torpoon's on the quarsteel. The sealmen were working in quick routine now; back and quickly forward, and then the crash and the reverberation; and again and again....

The ominous crash and ringing echoes regularly repeated, seemed to disorganise Ken's mind as he looked vainly for something with which to brace the door. Nothing unattached was left—nothing! He ran and examined the quarsteel pane again, and this time his brain heated in alarm. A thin line had shot through the quarsteel—the beginning of a crack.

"Back!" Ken shouted to the still staring Sallorsen. "Back to the third compartment. This door's going!"

"Yes," Sallorsen mumbled. "It'll go. So will the others. They'll smash them all. And when this is flooded—no hope of running the submarine again. Controls in here."

"That's too damned bad!" Ken said roughly. "Are there any sea-suits, food, supplies in here?"

"Only food. In those lockers."

"I'll take it. Get into that third compartment—hear me?" ordered Kenneth Torrance. "And have its door ready to close!"

He shoved Sallorsen away, opened the indicated lockers and piled his arms with the tins revealed. He had time for no more than one load. He jumped back into the third compartment of the Peary just as a splintering crash sounded from behind. The door between was swung closed and locked just as the one being battered crashed inward.

Turning, Ken saw that the torpoon had cracked through the weakened quarsteel and tumbled in a mad cascade of water to the deck of the abandoned second compartment. In dread silence, he, with Sallorsen and those of the men who had strength and curiosity enough to come forward, watched the compartment rapidly fill—watched until they saw the water pressed high against the door. And then horror swept over Ken Torrance.

Water! There was a trickle of water down the quarsteel he was leaning against! A fault along the hinge of the door—either its construction, or because it had not been closed properly.

Ken pointed it out to the captain.

"Look!" he said. "A leak already—just from the pressure! This door won't last more than a couple of minutes when they start on it—"

Sallorsen stared stupidly. As for the rest; Ken might not have spoken. They were as if in a trance, watching dumbly, with lungs automatically gasping for air.

One of the seal-creatures eeled through the shattered quarsteel of the first door and swam slowly around the newly flooded compartment. At once it was joined by five other lithe, sleek shapes which, with placid, liquid eyes, inspected the compartment minutely. They came in a group right up to the next door that barred their way and, with no visible emotion, stared through the quarsteel pane at the humans who stared at them. And then they gracefully turned and slid to the battered torpoon.

"Back!" Ken shouted, "You men!" He shook them, shoved them roughly back toward the fourth, and last, compartment. Weakly, like automatons they shuffled into it. The torpooner said bruskly to Sallorsen:

"Carry those tins of food back. Hurry! Is there anything stored in here we'll need? Sallorsen! Captain! Is there anything—"

The captain looked at him dully; then, understanding, a cackle came from his throat. "Don't need anything. This is the end. Last compartment. Finish!"

"Snap out of it!" Ken cried. "Come on, Sallorsen—there's a chance yet. Is there anything we'll need in here?"

"Sea-suits—in those lockers."

Ken Torrance swung around and rapidly opened the lockers. Pulling out the bulky suits, he cried:

"You carry that food back. Then come and help me."

But of the corner of his eye, as he worked, he could see the ominous preparations beyond in the flooded compartment—the sealmen raising the torpoon, guiding it back to the far end; leveling it out. Ken was sure the door could not stand more than two or three blows at the most. Two or three minutes, that meant—but all the sea-suits had to go back into the fourth compartment!

He was in torment as he worked. For him, the conditions were just as bad as for the men who had lived below in the submarine for a month; the poisonous, foul air racked him just as much; what breath he got he fought for just as painfully. But in his body was a greater store of strength, and fresher muscles; and he taxed his body to its very limit.

Panting, his head seeming on the point of splitting, Ken Torrance stumbled through into the last compartment laden with a pile of sea-suits. He dropped them clattering in a pile around his feet and forced himself back again. Another trip; and another....

It would never have been done had not Sallorsen and Lawson, the scientist, come to his aid. The help they offered was meager, and slow, but it sufficed. Laden for the fifth time, Ken heard what he had been anticipating for every second of the all too short, agonizing minutes: a sharp, grinding crack, and the following reverberation. He snatched a glance around to see the torpoon falling to the deck of the second compartment—the sealmen lifting it swiftly again—and a thin but definite sliver in the quarsteel of the door.

But the last suit was gotten into the fourth compartment, and the connecting door closed and carefully locked and bolted. The removal of the suits, had been achieved—but what now?

Panting, completely exhausted, Ken forced his brain to the question. From every side he attacked the problem, but nowhere could he find the loophole he sought. Everything, it seemed, had been tried, and had failed, during the Peary's long captivity. There was nothing left. True, he had his torpoon, and its nitro-shell gun with a clip of nineteen shells; but what use were shells? Even if each one accounted for one of the sealmen, there would still remain a swarm.

And the sea-suits. He had struggled for them and had saved them, but what use could he put them to? Go out leading a desperate final sally for the hole in the ice above? Death in minutes!

No hope. Nothing. Not even a fighting chance. These seal-creatures, strange seed of the Arctic ice, had trapped the Peary all too well. On the roll of mysteriously missing ships would her name go down; and he, Ken Torrance, would be considered a lunatic who had sought suicide, and found it....

Of the twenty-one survivors of the Peary's officers and crew, only a dozen had the will to watch the inexorable advance of the sealmen. The rest lay in various attitudes on the deck of the rear compartment, showing no sign of life save torturous, shallow pantings for air and, occasionally, spasmodic clutchings at their throats and chests, as they tried to fight off the deadly, invisible foe that was slowly strangling them.

Ken Torrance, Sallorsen, the scientist, Lawson, and a few others were pressed together at the last watertight door, peering through the quarsteel at the sea-creatures' systematic assault on the door leading into the third compartment. A straight, hard smash at it; another final splintering smash—and again the torpoon pushed through in the van of a cascade of icy, greenish water, which quickly claimed the control compartment for the attackers behind. The creatures were growing bolder. More and more of them had entered the submarine, and soon each open compartment was filled from deck to ceiling with the slowly turning, graceful brown bodies, inspecting minutely the countless wheels and levers and gauges, and inspecting also, in turns, the pale, worn faces that stared with dull eyes at them through the sole remaining door.

There was no further retreat, now. Behind was only water and the swarm that passed to and fro through it. Water and sealmen—ahead, above, to the sides, behind—everywhere. Cooped in their transparent cell, the crew of the submarine Peary waited the end.

Once more, as well as he could with his throbbing head and heavy, choking body, Kenneth Torrance tracked over the old road that had brought him nowhere, but was the only road open. Carefully he took stock of everything he had that he might possibly fight with.

There were sea-suits for the men, and in each suit an hour's supply of artificial but invigorating air. Two port-locks, one on each side of the stern compartment. A torpoon, with a gun and nineteen shells. Nothing else? There seemed to be, in his mind, a vague memory of something else ... something that might possibly be of use ... something.... But he could not remember. Again and again the agony of slow strangulation he was going through drove everything but the consciousness of pain from his shirking mind. But there was something else—and perhaps it was the key. Perhaps if he could only remember it—whatever it was—whether a tangible thing or merely a passing idea of hours ago—the way out would be suddenly revealed.

But he could not remember. He had the sea-suits, the port-locks and the torpoon: what possible pattern could he weave them into to bring deliverance?

No, there was nothing. Not even a girder that could be unfastened in time to brace the last door. No way of prolonging this last stand!

Beside Ken, the strained, panting voice of Lawson whispered:

"Getting ready. Over soon now. All over."

All save five of the sealmen had left the third compartment, to join the swarm constantly swimming around and over the submarine outside. The five remaining were the crew for the battering ram. With measured and deliberate movements they ranged their lithe bodies beside the torpoon, lifted it and bore it smoothly back to the far end of the compartment. There they poised for a minute, while from the men watching sounded a pathetic sigh of anticipation.

As one, the five seal-creatures lunged forward with their burden.

Crash! And the following dull reverberation.

The last assault had begun.