I pulled the door to behind me and followed Hansen out into the dreadful night.

We had been tired, more than tired, even before we had set out. We had been leaden-legged, bone-weary, no more than a short handspan from total exhaustion. But, for all that, we flitted through the howling darkness of that night like two great white ghosts across the dimly seen whiteness of a nightmare lunar landscape. We were no longer bowed under the weight of heavy packs. Our backs were to that gale-force wind, so that for every laborious plodding step we had made on our way to Zebra we now covered five, with so little a fraction of our earlier toil that at first it seemed all but effortless. We had no trouble in seeing where we were going, no fear of falling into an open lead or of crippling ourselves against some unexpected obstacle, for with our useless goggles removed and powerful flashlight beams dancing erratically ahead of us as we jog-trotted along, visibility was seldom less than five yards, more often nearer ten. Those were the physical aids that helped us on our way but even more sharply powerful as a spur to our aching legs was that keen and ever-growing fear that dominated our minds to the exclusion of all else, the fear that Commander Swanson had already been compelled to drop down and that we would be left to die in that shrieking wasteland: with our lacking both shelter and food, the old man with the scythe would not be keeping us waiting too long.

We ran, but we did not run too fast, for to have done that would have been to have the old man tapping us on the shoulder in very short order indeed. In far sub-zero temperatures, there is one thing that the Eskimo avoids as he would the plague — overexertion, in those latitudes more deadly, even, than the plague itself. Too much physical effort while wearing heavy furs inevitably results in sweat, and when the effort ceases, as eventually cease it must, the sweat freezes on the skin: the only way to destroy that film of ice is by further exertion, producing even more sweat, the beginnings of a vicious and steadily narrowing circle that can have only one end. So though we ran it was only at a gentle jog-trot, hardly more than a fast walk; we took every possible precaution against overheating.

After half an hour, perhaps a little more, I called for a brief halt in the shelter of a steep ice wall. Twice in the past two minutes Hansen had stumbled and fallen where there hadn't appeared to be any reason to stumble and fall: and I had noticed that my own legs were more unsteady than the terrain warranted.

"How are you making out?" I asked.

"Pretty bushed, Doc." He sounded it, too, his breathing quick and rasping and shallow. "But don't write me off yet. How far do you think we've come?"

"Three miles, near enough." I patted the ice wall behind us. "When we've had a couple of minutes, I think we should try climbing this. Looks like a pretty tall hummock to me."

"To try to get into the clear above the ice storm?" I nodded my head and he shook his. "Won't do any good, Doc. This ice storm must be at least twenty feet thick, and even if you do get above it the «Dolphin» will still be below it. She's only got the top of her sail clear above the ice."

"I've been thinking," I said. "We've been so lost in our own woes and sorrows that we've forgotten about Commander Swanson. I think we've been guilty of underestimating him pretty badly."

"It's likely enough. Right now I'm having a fulitime job worrying about Lieutenant Hansen. What's on your mind?"

"Just this. The chances are better than fifty-fifty that Swanson believes we're on our way back to the «Dolphin». After all, he's been ordering us to return for quite some time. And if he thinks we didn't get the order because something has happened to us or to the radio, he'll still figure that we will be returning."

"Not necessarily. Radio or not, we might still be heading for Drift Station Zebra."

"No. Definitely not. He'll be expecting us to be smart enough to figure it the way he would, and smart enough to see that that is the way «he» would figure it. He would know that if our radio broke down before we got to Zebra, it would be suicidal for us to try to find it without radio bearing — but that it «wouldn't» be suicidal for us to try to make it back to the «Dolphin», for he would be hoping that we would have sufficient savvy to guess that he would put a lamp in the window to guide the lost sheep home."

"My God, Doc, I think you've got it! Of course he would, of course he would. God, what am I using for brains?" He straightened and turned to face the ice wall.

Pushing and pulling, we made it together to the top. The summit of the rafted ice hummock was less than twenty feet above the level of the ice pack and not quite high enough. We were still below the surface of that gale-driven river of ice spicules. Occasionally, for a brief moment of time, the wind force would ease fractionally and let us have a brief glimpse of the clear sky above: but only occasionally and for a fraction of a second. And if there was anything to be seen in that time, we couldn't see it.

"There'll be other hummocks," I shouted in Hansen's ear. "Higher hummocks." He nodded without answering. I couldn't see the expression on his face but I didn't have to see it. The same thought was in both our minds: we could see nothing because there was nothing to see. Commander Swanson hadn't put a lamp in the window, for the window was gone, the «Dolphin» forced to dive to avoid being crushed by the ice.

Five times in the next twenty minutes we climbed hummocks, and five times we climbed down, each time more dejected, more defeated. By now I was pretty far gone, moving in a pain-filled nightmare: Hansen was in even worse shape, lurching and staggering around like a drunken man. As a doctor, I knew well the hidden and unsuspected resources that an exhausted man could call on in times of desperate emergency; but I knew too that those resources are not limitless and that we were pretty close to the end. And when that end came we would just lie down in the lee of an ice wall and wait for the old man to come along: he wouldn't keep us waiting long.

Our sixth hummock all but defeated us. It wasn't that it was hard to climb — it was well ridged with foot and hand holds — but the sheer physical effort of climbing came very close to defeating us. And then I dimly began to realize that part of the effort was owing to the fact that this was by far the highest hummock we had found yet. Some colossal pressures had concentrated on this one spot, rafting and logjamming the ice pack until it had risen a clear thirty feet above the general level; the giant underwater ridge beneath must have stretched down close to two hundred feet toward the black floor of the Arctic.

Eight feet below the summit our heads were in the clear: on the summit itself, holding on to each other for mutual support against the gale, we could look down on the ice storm whirling by just beneath our feet, a fantastic sight: a great gray-white sea of undulating turbulence, a giant rushing river that stretched from horizon to horizon. Like so much else in the high Arctic, the scene had an eerie and terrifying strangeness about it, a mindless desolation that belonged not to earth but to some alien and long-dead planet.

We scanned the horizon to the west until our eyes ached. Nothing. Nothing at all. Just that endless desolation. From due north to due south, through 1800, we searched the surface of that great river: and still we saw nothing. Three minutes passed. Still nothing. I began to feel the ice running in my blood.

On the remote off-chance that we might already have bypassed the «Dolphin» to the north or south, I turned and peered toward the east. It wasn't easy, for that gale of wind brought tears to the eyes in an instant of time, but at least it wasn't impossible; we no longer had to contend with the needlepointed lances of the ice spicules. I made another slow 180° sweep of the eastern horizon, and again, and again. Then I caught Hansen's arm.