But this did not suit Mr. Gibbs. He had a very strong desire to reach the waters of the little lake, because he knew that at their bottom lay the telegraphic cable which he had been obliged to abandon, and he had thought he might be able to raise this cable and re-establish telegraphic communication with Cape Tariff and New Jersey.

Sammy thought that Mr. Gibbs's desire could be accomplished by sinking into the water in which they now lay and sailing under the icebergs to the lake, but Mr. Gibbs did not favor this. He was afraid to go under the icebergs. To be sure, they had already sailed under one of them when the Dipsey had made her way northward from the lake, but they had found that the depth of water varied very much in different places, and the icebergs in front of them might be heavier, and therefore more deeply sunken, than those which they had previously passed under.

If it were possible to extend their canal to Lake Shiver, Mr. Gibbs wanted to do it, but if they should fail in this, then, of course, they would be obliged to go down at this or some adjacent spot.

“It's all very well,” said Captain Hubbell, who was a little depressed in spirits because the time was rapidly approaching when he would no longer command the vessel, “but it's one thing to blow a canal through fields of flat ice, and another to make it all the way through an iceberg; but if you think you can do it, I am content. I'd like to sail above water just as far as we can go.”

Mr. Gibbs had been studying the situation, and some ideas relating to the solution of the problem before him were forming themselves in his mind. At last he hit upon a plan which he thought might open the waters of Lake Shiver to the Dipsey, and, as it would not take very long to test the value of his scheme, it was determined to make the experiment.

There were but few on board who did not know that if a needle were inserted into the upper part of a large block of ice, and were then driven smartly into it, the ice would split. Upon this fact Mr. Gibbs based his theory of making an entrance to the lake.

A climbing party, larger than the previous one, set out for the iceberg, carrying with them, on several sledges, a long and heavy iron rod, which was a piece of the extra machinery on the Dipsey, and some explosives of a special kind.

When the iceberg had been reached, several of the party ascended with a hoisting apparatus, and with this the rod was hauled to the top and set up perpendicularly on a central spot at the summit of the iceberg, the pointed end downward, and a bomb of great power fastened to its upper end. This bomb was one designed to exert its whole explosive power in one direction, and it was so placed that this force would be exerted downward. When all was ready, the electric-wire attachment to the bomb was carried down the iceberg and carefully laid on the ice as the party returned to the Dipsey.

Everybody, of course, was greatly interested in this experiment. The vessel was at least two miles from the iceberg, but in the clear atmosphere the glittering eminence could be plainly seen, and, with a glass, the great iron rod standing high up on its peak was perfectly visible. All were on deck when Mr. Gibbs stood ready to discharge the bomb on top of the rod, and all eyes were fixed upon the iceberg.

There was an explosion—not very loud, even considering the distance—and those who had glasses saw the rod disappear downward. Then a strange grating groan came over the snow-white plain, and the great iceberg was seen to split in half, its two peaks falling apart from each other. The most distant of the two great sections toppled far backward, and with a great crash turned entirely over, its upper part being heavier than its base. It struck an iceberg behind it, slid upon the level ice below, crashed through this, and sank out of sight. Then it was seen to slowly rise again, but this time with its base uppermost. The other and nearest section, much smaller, fell against an adjacent iceberg, where it remained leaning for some minutes, but soon assumed an erect position. The line of cleavage had not been perpendicular, and the greater part of the base of the original iceberg remained upon the nearer section.