“Who came here the last time?” asked the engineer.

“I did, captain,” answered Ayrton.

“And that was—­”

“Four days ago.”

“Ah! a note!” cried Herbert, pointing to a paper lying on the table.

On this paper were written these words in English:—­

“Follow the new wire.”

“Forward!” cried Harding, who understood that the despatch had not been sent from the corral, but from the mysterious retreat, communicating directly with Granite House by means of a supplementary wire joined to the old one.

Neb took the lighted lantern, and all left the corral.  The storm then burst forth with tremendous violence.  The interval between each lightning-flash and each thunder-clap diminished rapidly.  The summit of the volcano, with its plume of vapor, could be seen by occasional flashes.

There was no telegraphic communication in any part of the corral between the house and the palisade; but the engineer, running straight to the first post, saw by the light of a flash a new wire hanging from the isolator to the ground.

“There it is!” said he.

This wire lay along the ground, and was surrounded with an isolating substance like a submarine cable, so as to assure the free transmission of the current.  It appeared to pass through the wood and the southern spurs of the mountain, and consequently it ran towards the west.

“Follow it!” said Cyrus Harding.

And the settlers immediately pressed forward, guided by the wire.

The thunder continued to roar with such violence that not a word could be heard.  However, there was no occasion for speaking, but to get forward as fast as possible.

Cyrus Harding and his companions then climbed the spur rising between the corral valley and that of Falls River, which they crossed at its narrowest part.  The wire, sometimes stretched over the lower branches of the trees, sometimes lying on the ground, guided them surely.  The engineer had supposed that the wire would perhaps stop at the bottom of the valley, and that the stranger’s retreat would be there.

Nothing of the sort.  They were obliged to ascend the south-western spur, and re-descend on that arid plateau terminated by the strangely-wild basalt cliff.  From time to time one of the colonists stooped down and felt for the wire with his hands; but there was now no doubt that the wire was running directly towards the sea.  There, to a certainty, in the depths of those rocks, was the dwelling so long sought for in vain.

The sky was literally on fire.  Flash succeeded flash.  Several struck the summit of the volcano in the midst of the thick smoke.  It appeared there as if the mountain was vomiting flame.  At a few minutes to eleven the colonists arrived on the high cliff overlooking the ocean to the west.  The wind had risen.  The surf roared 500 feet below.

Harding calculated that they had gone a mile and a half from the corral.