"Battle it is to be," said Polaris; "and yonder floats the enemy." He pointed to where a huge iceberg had broken from its mooring at the edge of the floe, and, momentarily gaining headway, was drifting in to bar the channel way. The ship swung about sharply. One of her powerful searchlights played steadily on the face of the looming ice cliffs as it came on, its hundred towers and crags glittering and flashing in the brilliant ray, a mass of floating silver. A sharp word of command, and the three gun captains, bronzed and alert, bent to their levers with machinelike precision. The crackling of the floes and the grinding of the bergs were lost in the thunder of the guns. At that point-blank range, the effect of the volley was terrific. Where the shells struck, the surface of the berg flew to pieces. The air in the radius of the searchlight was filled with a shower of scintillating splinters. Larger masses of ice slid from the face of the slow-moving mountain and plunged sullenly into the tossing waves. A cavern was made from which a thousand gleaming fissures shot into the darker body of the ice behind. Working like beavers, the gunners reloaded and sent another crashing discharge into the floating wall at its water-line. As a small chunk of ice is parted by a few blows from an ice pick, so the repeated impact of the exploding shells shattered the berg and sundered it. Pitching and toppling, down came its lofty towers into the sea. Its giant menace crumbled into scores of insignificant blocks and a spreading bank of drift. Again the _Minnetonka_ backed and pointed her nose toward the floe, whither her searchlights were concentrated. Scoland reappeared on the bridge. "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.