Many of the disasters which threaten us in this life pass us by. So it was with the impending disaster of piling ice near the submarine. It did not pile.

But there remained the problem of getting the submarine through that six-foot roof to the water beneath. How was it to be done?

The Doctor still paced back and forth, his unrest written in the furrows of his brow. The jackies, cheerful as ever, worked at their shift of repairing the craft, or, when not at work, played at "duck-on-rock" with chunks of ice. Once a seal appeared in a water-hole. Had he not departed promptly, there would have been fried seal steak and roast seal heart for supper. A lumbering bear, that had evidently never seen a human being before, was not so fortunate. His pelt was added to the trophies of the expedition, and his meat was ground into rather tough hamburger.

Finally the mechanics announced that the submarine was again in perfect condition. Now was the time to try Dave's last trick. Sending three men to stretch a hundred-fathom cable from the submarine, and to anchor its farther end to a great ice-pan, he dropped below to return at once with a package. Cautioning the men not to follow him, he walked away seventy-five yards, bent over the center of an ice-pan, seemingly to adjust certain things and put others in order. This done, he strung a black cord-like affair from his little pile of objects. He then measured off ten paces, and repeated these operations. He then lighted a small gasoline torch, and held the tip of the second cord-like affair to it, then raced to the other for the same purpose. When this was done, he sped away toward his companions. His actions were quickly understood by the watching crew. The furrows on the Doctor's brow had become mere lines. He was smiling hopefully. When Dave tripped over an ice boulder there was a cry of alarm, but he was up in a second, and found shelter with his men. Instinctively everyone ducked. Then came two roaring explosions in quick succession. Bits of splintered ice fell around them like hail. Before the ice fragments had ceased falling, everyone was climbing to the top of the ice-pile. What they saw caused a shout of joy. Where the ice-pan had been was a long stretch of black water that slowly widened until it was quite large enough to float the submarine and allow it to submerge.

At once every man was at his task. The submarine moved slowly toward the water. There followed a dip, a great splash, a wild "Hurrah!" and five minutes later they were once more on their way to the Pole.

But, during this time, Dave's active mind had been working on another problem, which might appear to have been settled, but had not been: the drift of the floe. If the ice did not pile when the floes came together, why was it? It seemed to him there could be but one answer; other water-channels beyond the drift, under which they now traveled, were being closed by counter-currents. And if they closed, one after the other, more rapidly than the advance of the submarine, what was finally to become of the submarine crew? Would they not perish for lack of air? Dave did not share the cheerful mood of the Doctor and the crew; it was his turn to look worried.

Many hours later, his worst fears having been realized, he found himself again in the little room of many wheels and dials. Hour after hour they had shot beneath the varying surface of the floe, but not for one hopeful second had they caught the dark shadow of open water. As near as he could reckon, allowing for the ever-present currents, Dave believed they were nearing the Pole. But his brain was now throbbing as if a hundred trip-hammers were pounding upon it. Moments alone would tell the tale, for the oxygen in the air was exhausted. Already half the crew were unconscious; others were reeling like drunken men. The Doctor had been the first to succumb to the poison of polluted air.

In this crisis Dave was not alone at the wheel. The Eskimo boy, Azazruk, was by his side. It was for just such a time as this that he had taught the bright young native something of the control of the mechanism.

Each wheel of the operating devices was numbered. He had taught the
Eskimo a formula by pains-taking repetition.

"If ever the time comes when all are sick, no one can move but you," he had said many times, "and if at that time you see black waters above, act quickly. One—seven—ten—three—five, remember that. One wheel at a time, quickly but surely; one—seven—ten—three—five."