Top’s instinct was useful to the hunters, who, thanks to the intelligent animal, were enabled to discover the road by which they had come.  Half an hour later they arrived at the river.

Pencroft soon made a raft of wood, as he had done before, though if there was no fire it would be a useless task, and the raft following the current, they returned towards the Chimneys.

But the sailor had not gone fifty paces when he stopped, and again uttering a tremendous hurrah, pointed towards the angle of the cliff,—­

“Herbert!  Neb!  Look!” he shouted.

Smoke was escaping and curling up among the rocks.

Chapter 10

In a few minutes the three hunters were before a crackling fire.  The captain and the reporter were there.  Pencroft looked from one to the other, his capybara in his hand, without saying a word.

“Well, yes, my brave fellow,” cried the reporter.

“Fire, real fire, which will roast this splendid pig perfectly, and we will have a feast presently!”

“But who lighted it?” asked Pencroft.

“The sun!”

Gideon Spilett was quite right in his reply.  It was the sun which had furnished the heat which so astonished Pencroft.  The sailor could scarcely believe his eyes, and he was so amazed that he did not think of questioning the engineer.

“Had you a burning-glass, sir?” asked Herbert of Harding.

“No, my boy,” replied he, “but I made one.”

And he showed the apparatus which served for a burning-glass.  It was simply two glasses which he had taken from his own and the reporter’s watches.  Having filled them with water and rendered their edges adhesive by means of a little clay, he thus fabricated a regular burning-glass, which, concentrating the solar rays on some very dry moss, soon caused it to blaze.

The sailor considered the apparatus; then he gazed at the engineer without saying a word, only a look plainly expressed his opinion that if Cyrus Harding was not a magician, he was certainly no ordinary man.  At last speech returned to him, and he cried,—­

“Note that, Mr. Spilett, note that down on your paper!”

“It is noted,” replied the reporter.

Then, Neb helping him, the seaman arranged the spit, and the capybara, properly cleaned, was soon roasting like a suckling-pig before a clear, crackling fire.

The Chimneys had again become more habitable, not only because the passages were warmed by the fire, but because the partitions of wood and mud had been re-established.

It was evident that the engineer and his companions had employed their day well.  Cyrus Harding had almost entirely recovered his strength, and had proved it by climbing to the upper plateau.  From this point his eye, accustomed to estimate heights and distances, was fixed for a long time on the cone, the summit of which he wished to reach the next day.  The mountain, situated about six miles to the northwest, appeared to him to measure 3,500 feet above the level of the sea.  Consequently the gaze of an observer posted on its summit would extend over a radius of at least fifty miles.  Therefore it was probable that Harding could easily solve the question of “island or continent,” to which he attached so much importance.