"Fire!" he shouted frenziedly through his megaphone.
A dark figure on the floe let its hand fall on the battery knob. A succession of thunderous detonations followed, and from every lyddite mine was flung skyward a column of water and glittering debris. For many yards the mighty floe pitched and heaved.
Her twin propellers thrashing the water to foam, the Minnetonka drove her steel-clad length through the opened gap smashing the wreckage right and left, and came to rest in the basin beyond. She was scarcely in before, with a long, angry roaring, the great rift closed behind her.
As the cruiser pushed through the channel a cry of consternation rose from the men on the ice, drowned in the turmoil of her passing, but audible to one man on her decks whose ears were almost more than mortal keen. Another cry came from the gunners as Polaris dashed through them and hurled himself into the ice-strewn waters.
One of Scoland's sailors, separated by some distance from his fellows, had climbed to an icy eminence near the west side of the basin. In the disturbance which followed the blasting of the channel and its closing, the ice where he stood had parted from the floe, and, his footing riven from under him, the poor fellow had been pitched into the dark water in the midst of the pounding drift.
From the deck of the cruiser, Polaris heard his despairing cry, and, straining his eyes through the half twilight, saw his form silhouetted for an instant against the ice before he took the plunge.
Straight and true leaped the son of the snows. One of the things civilization had taught him that he had never known before was the art of swimming. The staring gunners saw his white-clad figure reappear once many feet distant from the side of the cruiser, and then he was gone, tearing his way with powerful strokes through the swirl of ice and water.
As fast as many willing hands could cast her loose, a boat was put out from the ship. The miners on the ice rushed to the spot where their comrade had disappeared. Across the drift one of the cruiser's searchlights swept a long finger of light. It played on sullen waves and heaving ice, but revealed no struggling swimmer.
"That is the last of Janess, and the finish of this expedition," rapped out Scoland.
Zenas Wright, standing at the rail of the ship beside him, groaned aloud. He did not see the fleeting, satisfied smile that accompanied the words of Scoland. A mist that was not of the air or sea rose and obscured his vision, and he wiped it away with his shaking old hand.