The flashes gradually became brighter and more rapid. Distant thunder growled in the sky. The atmosphere was stifling.

The colonists proceeded as if they were urged onwards by some irresistible force.

At ten o'clock a vivid flash showed them the palisade, and as they reached the gate the storm burst forth with tremendous fury.

In a minute the corral was crossed, and Harding stood before the hut.

Probably the house was occupied by the stranger, since it was from thence that the telegram had been sent. However, no light shone through the window.

The engineer knocked at the door.

No answer.

Cyrus Harding opened the door, and the settlers entered the room, which was perfectly dark. A light was struck by Neb, and in a few moments the lantern was lighted and the light thrown into every corner of the room.

There was no one there. Everything was in the state in which it had been left.

"Have we been deceived by an illusion?" murmured Cyrus Harding.

No! that was not possible! The telegram had clearly said--

"Come to the corral immediately."

They approached the table specially devoted to the use of the wire.

Everything was in order--the pile and the box containing it, as well as all the apparatus.

"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 vapour, 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 isolater 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 a.s.sure the free transmission of the current. It appeared to pa.s.s 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 coral.

At this point the wire entered among the rocks, following the steep side of a narrow ravine. The settlers followed it at the risk of occasioning a fall of the slightly-balanced rocks, and being dashed into the sea.

The descent was extremely perilous, but they did not think of the danger; they were no longer masters of themselves, and an irresistible attraction drew them towards this mysterious place as the magnet draws iron.

Thus they almost unconsciously descended this ravine, which even in broad daylight would have been considered impracticable.

The stones rolled and sparkled like fiery b.a.l.l.s when they crossed through the gleams of light. Harding was first--Ayrton last. On they went, step by step. Now they slid over the slippery rock; then they struggled to their feet and scrambled on.

At last the wire touched the rocks on the beach. The colonists had reached the bottom of the basalt cliff.

There appeared a narrow ridge, running horizontally and parallel with the sea. The settlers followed the wire along it. They had not gone a hundred paces when the ridge by a moderate incline sloped down to the level of the sea.

The engineer seized the wire and found that it disappeared beneath the waves.

His companions were stupefied.

A cry of disappointment, almost a cry of despair, escaped them! Must they then plunge beneath the water and seek there for some submarine cavern? In their excited state they would not have hesitated to do it.

The engineer stopped them.

He led his companions to a hollow in the rocks, and there--

"We must wait," said he. "The tide is high. At low-water the way will be open."

"But what can make you think--" asked Pencroft.

"He would not have called us if the means had been wanting to enable us to reach him!"

Cyrus Harding spoke in a tone of such thorough conviction that no objection was raised. His remark, besides, was logical. It was quite possible that an opening, practicable at low-water, though hidden now by the high tide, opened at the foot of the cliff.

There was some time to wait. The colonists remained silently crouching in a deep hollow. Rain now began to fall in torrents. The thunder was re-echoed among the rocks with a grand sonorousness.

The colonists' emotion was great. A thousand strange and extraordinary ideas crossed their brains, and they expected some grand and superhuman apparition, which alone could come up to the notion they had formed of the mysterious genius of the island.

At midnight, Harding, carrying the lantern, descended to the beach to reconnoitre.