A thin, dark line was spreading rapidly along the face of the ice-cliffs, and even as he gazed it widened, and a huge mass of ice, thousands of tons in weight, leaned outward. For an instant it hung poised, then thundered downward.
The enormity of the peril appalled Mervyn! He stood as one spellbound. It seemed as though naught could save the Seal and her crew from utter destruction; yet, in the very instant of her dire peril, deliverance came in a marvellous manner.
There came a sharp snap from the stern, and the Seal, leaping forward like hound from leash, passed clear beneath the huge, descending mass, and sped seaward. Her cable had parted!
A fearful roar, a mighty wave which almost swept Mervyn from the deck, an avalanche of falling fragments, then the whole thing was over.
As the last of the débris plunged into the seething water, and before the scientist had recovered from the shock, his comrades, awakened by the uproar, darted out on deck.
“Whatever has happened?” Garth gasped, gazing in amazement at Mervyn’s ashen-white face, and then at the rapidly receding ice-cliffs.
Somehow Mervyn stammered through his explanation.
“Great Scott!” Seymour cried, as the scientist finished, “if the cable hadn’t parted, the Seal would have been crushed like an egg-shell!”
“It was a close call,” Haverly broke in. “I guess we must ha’ struck a fairly healthy current, to snap the cable like that. However, all’s well as ends right side up.”
He grasped the wheel as he spoke, and the engineer, who had hurried on deck with his friends at the alarm, went below once more to his engines.