Having arrived at the bottom of one of those sombre cavities, which extended several hundred feet into the interior of the mountain, he was surprised to hear deep muttering sounds which were intensified by the sonority of the rocks. Spilett, who was with him, also heard these distant murmurs, which indicated an awakening of the subterranean fires. Several times they listened, and they came to the conclusion that some chemical reaction was going on in the bowels of the earth. “The volcano is not entirely extinct,” said the reporter. “It is possible that, since our exploration of the crater, something has happened in its lower regions. All volcanoes, even those which are said to be extinct, can, evidently, become active again.” “But if Mount Franklin is preparing for another eruption, is not Lincoln Island in danger?” “I don’t think so,” answered the engineer, “The crater, that is to say, the safety-valve, exists, and the overflow of vapors and lavas will escape, as heretofore, by its accustomed outlet.” “Unless the lavas make a new passage towards the fertile parts of the island.” “Why, my dear Spilett, should they not follow their natural course?” “Well, volcanoes are capricious.” “Notice,” said Smith, “that all the slope of the mountain favors the flow of eruptive matter towards the valleys which we are traversing at present. It would take an earthquake to so change the centre of gravity of the mountain as to modify this slope.” “But an earthquake is always possible under these conditions.” “True,” replied the engineer, “especially when the subterranean forces are awakening, and the bowels of the earth, after a long repose, chance to be obstructed. You are right, my dear Spilett, an eruption would be a serious thing for us, and it would be better if this volcano has not the desire to wake up; but we can do nothing. Nevertheless, in any case, I do not think Prospect Plateau could be seriously menaced. Between it and the lake there is quite a depression in the land, and even if the lavas took the road to the lake, they would be distributed over the downs and the parts adjoining Shark Gulf.” “We have not yet seen any smoke from the summit, indicating a near eruption,” said Spilett. “No,” answered the engineer, “not the least vapor has escaped from the crater. It was but yesterday that I observed its upper part. But it is possible that rocks, cinders, and hardened lavas have accumulated in the lower part of its chimney, and, for the moment, this safety-valve is overloaded. But, at the first serious effort, all obstacles will disappear, and you may be sure, my dear Spilett, that neither the island, which is the boiler, nor the volcano, which is the valve, will burst under the pressure. Nevertheless, I repeat, it is better to wish for no eruption.” “And yet we are not mistaken,” replied the reporter. “We plainly hear ominous rumblings in the depths of the volcano!”