So, then, all was explained by the submarine explosion of this torpedo. Cyrus Harding could not be mistaken, as, during the war of the Union, he had had occasion to try these terrible engines of destruction. It was under the action of this cylinder, charged with some explosive substance, nitro- glycerine, picrate, or some other material of the same nature, that the water of the channel had been raised like a dome, the bottom of the brig crushed in, and she had sunk instantly, the damage done to her hull being so considerable that it was impossible to refloat her. The "Speedy" had not been able to withstand a torpedo that would have destroyed an ironclad as easily as a fishing-boat!

Yes! all was explained, everything--except the presence of the torpedo in the waters of the channel!

"My friends, then," said Cyrus Harding, "we can no longer be in doubt as to the presence of a mysterious being, a castaway like us, perhaps, abandoned on our island, and I say this in order that Ayrton may be acquainted with all the strange events which have occurred during these two years. Who this beneficent stranger is, whose intervention has, so fortunately for us, been manifested on many occasions, I cannot imagine. What his object can be in acting thus, in concealing himself after rendering us so many services, I cannot understand: But his services are not the less real, and are of such a nature that only a man possessed of prodigious power, could render them. Ayrton is indebted to him as much as we are, for, if it was the stranger who saved me from the waves after the fall from the balloon, evidently it was he who wrote the document, who placed the bottle in the channel, and who has made known to us the situation of our companion. I will add that it was he who guided that chest, provided with everything we wanted, and stranded it on Flotsam Point; that it was he who lighted that fire on the heights of the island, which permitted you to land; that it was he who fired that bullet found in the body of the peccary; that it was he who plunged that torpedo into the channel, which destroyed the brig; in a word, that all those inexplicable events, for which we could not assign a reason, are due to this mysterious being. Therefore, whoever he may be, whether shipwrecked, or exiled on our island, we shall be ungrateful, if we think ourselves freed from gratitude towards him. We have contracted a debt, and I hope that we shall one day pay it."

"You are right in speaking thus, my dear Cyrus," replied Gideon Spilett. "Yes, there is an almost all-powerful being, hidden in some part of the island, and whose influence has been singularly useful to our colony. I will add that the unknown appears to possess means of action which border on the supernatural, if in the events of practical life the supernatural were recognizable. Is it he who is in secret communication with us by the well in Granite House, and has he thus a knowledge of all our plans? Was it he who threw us that bottle, when the vessel made her first cruise? Was it he who threw Top out of the lake, and killed the dugong? Was it he, who as everything leads us to believe, saved you from the waves, and that under circumstances in which any one else would not have been able to act? If it was he, he possesses a power which renders him master of the elements."

The reporter's reasoning was just, and every one felt it to be so.

"Yes," rejoined Cyrus Harding, "if the intervention of a human being is not more questionable for us, I agree that he has at his disposal means of action beyond those possessed by humanity. There is a mystery still, but if we discover the man, the mystery will be discovered also. The question, then, is, ought we to respect the incognito of this generous being, or ought we to do everything to find him out? What is your opinion on the matter?"

"My opinion," said Pencroft, "is that, whoever he may be, he is a brave man, and he has my esteem!"

"Be it so," answered Harding, "but that is not an answer, Pencroft."

"Master," then said Neb, "my idea is, that we may search as long as we like for this gentleman whom you are talking about, but that we shall not discover him till he pleases."

"That's not bad, what you say, Neb," observed Pencroft.

"I am of Neb's opinion," said Gideon Spilett, "but that is no reason for not attempting the adventure. Whether we find this mysterious being or not, we shall at least have fulfilled our duty towards him."

"And you, my boy, give us your opinion," said the engineer, turning to Herbert.

"Oh," cried Herbert, his countenance full of animation, "how I should like to thank him, he who saved you first, and who has now saved us!"

"Of course, my boy," replied Pencroft, "so would I and all of us. I am not inquisitive, but I would give one of my eyes to see this individual face to face! It seems to me that he must be handsome, tall, strong, with a splendid beard, radiant hair, and that he must be seated on clouds, a great ball in his hands!"

"But, Pencroft," answered Spilett, "you are describing a picture of the Creator."

"Possibly, Mr. Spilett," replied the sailor, "but that is how I imagine him!"

"And you, Ayrton?" asked the engineer.

"Captain Harding," replied Ayrton, "I can give you no better advice in this matter. Whatever you do will be best; when you wish me to join you in your researches, I am ready to follow you.

"I thank you, Ayrton," answered Cyrus Harding, "but I should like a more direct answer to the question I put to you. You are our companion; you have already endangered your life several times for us, and you, as well as the rest, ought to be consulted in the matter of any important decision. Speak, therefore."

"Captain Harding," replied Ayrton, "I think that we ought to do everything to discover this unknown benefactor. Perhaps he is alone. Perhaps he is suffering. Perhaps he has a life to be renewed. I, too, as you said, have a debt of gratitude to pay him. It was he, it could be only he who must have come to Tabor Island, who found there the wretch you knew, and who made known to you that there was an unfortunate man there to be saved. Therefore it is, thanks to him, that I have become a man again. No, I will never forget him!"

"That is settled, then," said Cyrus Harding. "We will begin our researches as soon as possible. We will not leave a corner of the island unexplored. We will search into its most secret recesses, and will hope that our unknown friend will pardon us in consideration of our intentions!"

For several days the colonists were actively employed in haymaking and the harvest. Before putting their project of exploring the yet unknown parts of the island into execution, they wished to get all possible work finished. It was also the time for collecting the various vegetables from the Tabor Island plants. All was stowed away, and happily there was no want of room in Granite House, in which they might have housed all the treasures of the island. The products of the colony were there, methodically arranged, and in a safe place, as may be believed, sheltered as much from animals as from man.

There was no fear of damp in the middle of that thick mass of granite. Many natural excavations situated in the upper passage were enlarged either by pick-axe or mine, and Granite House thus became a general warehouse, containing all the provisions, arms, tools, and spare utensils--in a word, all the stores of the colony.

As to the guns obtained from the brig, they were pretty pieces of ordnance, which, at Pencroft's entreaty, were hoisted by means of tackle and pulleys, right up into Granite House; embrasures were made between the windows, and the shining muzzles of the guns could soon be seen through the granite cliff. From this height they commanded all Union Bay. It was like a little Gibraltar, and any vessel anchored off the islet would inevitably be exposed to the fire of this aerial battery.

"Captain," said Pencroft one day, it was the 8th of November, "now that our fortifications are finished, it would be a good thing if we tried the range of our guns."

"Do you think that is useful?" asked the engineer.

"It is more than useful, it is necessary! Without that how are we to know to what distance we ca............