At this moment Top, who had been very quiet till then, gave signs of agitation.The intelligent animal went backwards and forwards on the shore, stopped suddenly, and looked at the water, one paw raised, as if he was pointing at some invisible game; then he barked furiously, and was suddenly silent.
Neither Cyrus Harding nor his companions had at first paid any attention to Top's behavior; but the dog's barking soon became so frequent that the engineer noticed it.
"What is there, Top?" he asked.
The dog bounded towards his master, seeming to be very uneasy, and then rushed again towards the bank.Then, all at once, he plunged into the lake.
"Here, Top!" cried Cyrus Harding, who did not like his dog to venture into the treacherous water.
"What's happening down there?" asked Pencroft, examining the surface of the lake.
"Top smells some amphibious creature," replied Herbert.
"An alligator, perhaps," said the reporter.
"I do not think so," replied Harding."Alligators are only met with in regions less elevated in latitude."Meanwhile Top had returned at his master's call, and had regained the shore: but he could not stay quiet; he plunged in among the tall grass, and guided by instinct, he appeared to follow some invisible being which was slipping along under the surface of the water.However the water was calm;not a ripple disturbed its surface.Several times the settlers stopped on the bank, and observed it attentively.Nothing appeared.There was some mystery there.
The engineer was puzzled.
"Let us pursue this exploration to the end," said he.
Half an hour after they had all arrived at the southeast angle of the lake, on Prospect Heights.At this point the examination of the banks of the lake was considered finished, and yet the engineer had not been able to discover how and where the waters were discharged."There is no doubt this overflow exists," he repeated, and since it is not visible it must go through the granite cliff at the west!""But what importance do you attach to knowing that, my dear Cyrus?" asked Gideon Spilett.
"Considerable importance," replied the engineer; "for if it flows through the cliff there is probably some cavity, which it would be easy to render habitable after turning away the water.""But is it not possible, captain, that the water flows away at the bottom of the lake," said Herbert, "and that it reaches the sea by some subterranean passage?""That might be," replied the engineer, "and should it be so we shall be obliged to build our house ourselves, since nature has not done it for us."The colonists were about to begin to traverse the plateau to return to the Chimneys, when Top gave new signs of agitation.He barked with fury, and before his master could restrain him, he had plunged a second time into the lake.
All ran towards the bank.The dog was already more than twenty feet off, and Cyrus was calling him back, when an enormous head emerged from the water, which did not appear to be deep in that place.
Herbert recognized directly the species of amphibian to which the tapering head, with large eyes, and adorned with long silky mustaches, belonged.
"A lamantin!" he cried.
It was not a lamantin, but one of that species of the order of cetaceans, which bear the name of the "dugong," for its nostrils were open at the upper part of its snout.The enormous animal rushed on the dog, who tried to escape by returning towards the shore.His master could do nothing to save him, and before Gideon Spilett or Herbert thought of bending their bows, Top, seized by the dugong, had disappeared beneath the water.
Neb, his iron-tipped spear in his hand, wished to go to Top's help, and attack the dangerous animal in its own element.
"No, Neb," said the engineer, restraining his courageous servant.
Meanwhile, a struggle was going on beneath the water, an inexplicable struggle, for in his situation Top could not possibly resist; and judging by the bubbling of the surface it must be also a terrible struggle, and could not but terminate in the death of the dog! But suddenly, in the middle of a foaming circle, Top reappeared.Thrown in the air by some unknown power, he rose ten feet above the surface of the lake, fell again into the midst of the agitated waters, and then soon gained the shore, without any severe wounds, miraculously saved.
Cyrus Harding and his companions could not understand it.What was not less inexplicable was that the struggle still appeared to be going on.
Doubtless, the dugong, attacked by some powerful animal, after having released the dog, was fighting on its own account.But it did not last long.The water became red with blood, and the body of the dugong, emerging from the sheet of scarlet which spread around, soon stranded on a little beach at the south angle of the lake.The colonists ran towards it.The dugong was dead.It was an enormous animal, fifteen or sixteen feet long, and must have weighed from three to four thousand pounds.At its neck was a wound, which appeared to have been produced by a sharp blade.
What could the amphibious creature have been, who, by this terrible blow had destroyed the formidable dugong? No one could tell, and much interested in this incident, Harding and his companions returned to the Chimneys.