Cyrus Harding and Ayrton, with these impediments,
to make rapid progress. Moreover, the atmosphere was close, as if the
oxygen had been partly burned up, and had become unfit for respiration.
At every hundred paces they were obliged to stop to take breath. It was
therefore past ten o'clock when the engineer and his companion reached
the crest of the enormous mass of rocks of basalt and porphyry which
composed the northwest coast of the island.

Ayrton and Cyrus Harding commenced the descent of this abrupt declivity,
following almost step for step the difficult path which, during that
stormy night, had led them to Dakkar Grotto. In open day the descent was
less perilous, and, besides, the bed of ashes which covered the polished
surface of the rock enabled them to make their footing more secure.

The ridge at the end of the shore, about forty feet in height, was soon
reached. Cyrus Harding recollected that this elevation gradually sloped
towards the level of the sea. Although the tide was at present low, no
beach could be seen, and the waves, thickened by the volcanic dust, beat
upon the basaltic rocks.

Cyrus Harding and Ayrton found without difficulty the entrance to Dakkar
Grotto, and paused for a moment at the last rock before it.

"The iron boat should be there," said the engineer.

"It is here, Captain Harding," replied Ayrton, drawing towards him the
fragile craft, which was protected by the arch of the vault.

"On board, Ayrton!"

The two colonists stepped into the boat. A slight undulation of the
waves carried it farther under the low arch of the crypt, and there
Ayrton, with the aid of flint and steel, lighted the lamp. He then took
the oars, and the lamp having been placed in the bow of the boat, so
that its rays fell before them, Cyrus Harding took the helm and steered
through the shades of the grotto.

The "Nautilus" was there no longer to illuminate the cavern with its
electric light. Possibly it might not yet be extinguished, but no ray
escaped from the depths of the abyss in which reposed all that was
mortal of Captain Nemo.

The light afforded by the lamp, although feeble, nevertheless enabled
the engineer to advance slowly, following the wall of the cavern. A
deathlike silence reigned under the vaulted roof, or at least in the
anterior portion, for soon Cyrus Harding distinctly heard the rumbling
which proceeded from the bowels of the mountain.

"That comes from the volcano," he said.

Besi