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 o