"Poor man!" said Herbert, who had rushed to the door, but returned, having seen Ayrton slide down the rope on the lift and disappear in the darkness.

"He will come back," said Cyrus Harding.

"Come, now, captain," exclaimed Pencroft, "what does that mean? What! wasn't it Ayrton who threw that bottle into the sea? Who was it then?"

Certainly, if ever a question was necessary to be made, it was that one!

"It was he," answered Neb, "only the unhappy man was half-mad."

"Yes!" said Herbert, "and he was no longer conscious of what he was doing."

"It can only be explained in that way, my friends," replied Harding quickly, "and I understand now how Ayrton was able to point out exactly the situation of Tabor Island, since the events which had preceded his being left on the island had made it known to him."

"However," observed Pencroft, "if he was not yet a brute when he wrote that document, and if he threw it into the sea seven or eight years ago, how is it that the paper has not been injured by damp?"

"That proves," answered Cyrus Harding, "that Ayrton was deprived of intelligence at a more recent time than he thinks."

"Of course it must be so," replied Pencroft, "without that the fact would be unaccountable."

"Unaccountable indeed," answered the engineer, who did not appear desirous to prolong the conversation.

"But has Ayrton told the truth?" asked the sailor.

"Yes," replied the reporter. "The story which he has told is true in every point. I remember quite well the account in the newspapers of the yacht expedition undertaken by Lord Glenarvan, and its result."

"Ayrton has told the truth," added Harding. "Do not doubt it, Pencroft, for it was painful to him. People tell the truth when they accuse themselves like that!"

The next day--the 21st of December--the colonists descended to the beach, and having climbed the plateau they found nothing of Ayrton. He had reached his house in the corral during the night and the settlers judged it best not to agitate him by their presence. Time would doubtless perform what sympathy had been unable to accomplish.

Herbert, Pencroft, and Neb resumed their ordinary occupations. On this day the same work brought Harding and the reporter to the workshop at the Chimneys.

"Do you know, my dear Cyrus," said Gideon Spilett, "that the explanation you gave yesterday on the subject of the bottle has not satisfied me at all! How can it be supposed that the unfortunate man was able to write that document and throw the bottle into the sea without having the slightest recollection of it?"

"Nor was it he who threw it in, my dear Spilett."

"You think then--"

"I think nothing, I know nothing!" interrupted Cyrus Harding. "I am content to rank this incident among those which I have not been able to explain to this day!"

"Indeed, Cyrus," said Spilett, "these things are incredible! Your rescue, the case stranded on the sand, Top's adventure, and lastly this bottle... Shall we never have the answer to these enigmas?"

"Yes!" replied the engineer quickly, "yes, even if I have to penetrate into the bowels of this island!"

"Chance will perhaps give us the key to this mystery!"

"Chance! Spilett! I do not believe in chance, any more than I believe in mysteries in this world. There is a reason for everything unaccountable which has happened here, and that reason I shall discover. But in the meantime we must work and observe."

The month of January arrived. The year 1867 commenced. The summer occupations were assiduously continued. During the days which followed, Herbert and Spilett having gone in the direction of the corral, ascertained that Ayrton had taken possession of the habitation which had been prepared for him. He busied himself with the numerous flock confided to his care, and spared his companions the trouble of coming every two or three days to visit the corral. Nevertheless, in order not to leave Ayrton in solitude for too long a time, the settlers often paid him a visit.

It was not unimportant either, in consequence of some suspicions entertained by the engineer and Gideon Spilett, that this part of the island should be subject to a surveillance of some sort, and that Ayrton, if any incident occurred unexpectedly, should not neglect to inform the inhabitants of Granite House of it.

Nevertheless it might happen that something would occur which it would be necessary to bring rapidly to the engineer's knowledge. Independently of facts bearing on the mystery of Lincoln Island, many others might happen, which would call for the prompt interference of the colonists,--such as the sighting of a vessel, a wreck on the western coast, the possible arrival of pirates, etc.

Therefore Cyrus Harding resolved to put the corral in instantaneous communication with Granite House.

It was on the 10th of January that he made known his project to his companions.

"Why! how are you going to manage that, captain?" asked Pencroft. "Do you by chance happen to think of establishing a telegraph?"

"Exactly so," answered the engineer.

"Electric?" cried Herbert.

"Electric," replied Cyrus Harding. "We have all the necessary materials for making a battery, and the most difficult thing will be to stretch the wires, but by means of a drawplate I think we shall manage it."

"Well, after that," returned the sailor, "I shall never despair of seeing ourselves some day rolling along on a railway!"

They then set to work, beginning with the most difficult thing, for, if they failed in that, it would be useless to manufacture the battery and other accessories.

The iron of Lincoln Island, as has been said, was of excellent quality, and consequently very fit for being drawn out. Harding commenced by manufacturing a drawplate, that is to say, a plate of steel, pierced with conical holes of different sizes, which would successively bring the wire to the wished-for tenacity. This piece of steel, after having been tempered, was fixed in as firm a way as possible in a solid framework planted in the ground, only a few feet from the great fall, the motive power of which the engineer intended to utilize. In fact as the fulling- mill was there, although not then in use, its beam moved with extreme power would serve to stretch out the wire by rolling it round itself. It was a delicate operation, and required much care. The iron, prepared previously in long thin rods, the ends of which were sharpened with the file, having been introduced into the largest hole of the drawplate, was drawn out by the beam which wound it round itself, to a length of twenty-five or thirty feet, then unrolled, and the same operation was performed successively through the holes of a less size. Finally, the engineer obtained wires from forty to fifty feet long, which could be easily fastened together and stretched over the distance of five miles, which separated the corral from the bounds of Granite House.

It did not take more than a few days to perform this work, and indeed as soon as the machine had been commenced, Cyrus Harding left his companions to follow the trade of wiredrawers, and occupied himself with manufacturing his battery.

It was necessary to obtain a battery with a constant current. It is known that the elements of modern batteries are generally composed of retort coal, zinc, and copper. Copper was absolutely wanting to the engineer, who, notwithstanding all his researches, had never been able to find any trace of it in Lincoln Island, and was therefore obliged to do without it. Retort coal, that is to say, the hard graphite which is found in the retorts of gas manufactories, after the coal has been dehydrogenized, could have been obtained, but it would have been necessary to establish a special apparatus, involving great labor. As to zinc, it may be remembered that the case found at Flotsam Point was lined with this metal, which could not be better utilized than for this purpose.

Cyrus Harding, after mature consideration, decided to manufacture a very simple battery, resembling as nearly as possible that invented by Becquerel in 1820, and in which zinc only is employed. The other substances, azotic acid and potash, were all at his disposal.

The way in which the battery was composed was as follows, and the results were to be attained by the reaction of acid and potash on each other. A number of glass bottles were made and filled with azotic acid. The engineer corked them by means of a stopper through which passed a glass tube, bored at its lower extremity, and intended to be plunged into the acid by means of a clay stopper secured by a rag. Into this tube, through its upper extremity, he poured a solution of potash, previously obtained by burning and reducing to ashes various plants, and in this way the acid and potash could act on each other through the clay.

Cyrus Harding then took two slips of zinc, one of which was plunged into azotic acid, the other into a solution of potash. A current was immediately produced, which was transmitted from the slip of zinc in the bottle to that in the tube, and the two slips having been connected by a metallic wire the slip in the tube became the positive pole, and that in the bottle the negative pole of the apparatus. Each bottle, therefore, produced as many currents as united would be sufficient to produce all the phenomena of the electric telegraph. Such was the ingenious and very simple apparatus constructed by Cyrus Harding, an apparatus which would allow them to establish a telegraphic communication between Granite House and the corral.

On the 6th of February was commenced the planting along the roa............