Yes," replied Herbert, "two months and a half ago!"

"The subterranean fires have therefore been smoldering for ten weeks,"
resumed Gideon Spilett, "and it is not to be wondered at that they now
break out with such violence!"

"Do not you feel a certain vibration of the soil?" asked Cyrus Harding.

"Yes," replied Gideon Spilett, "but there is a great difference between
that and an earthquake."

"I do not affirm that we are menaced with an earthquake," answered Cyrus
Harding, "may God preserve us from that! No; these vibrations are due to
the effervescence of the central fire. The crust of the earth is
simply the shell of a boiler, and you know that such a shell, under the
pressure of steam, vibrates like a sonorous plate. It is this effect
which is being produced at this moment."

"What magnificent flames!" exclaimed Herbert.

At this instant a kind of bouquet of flames shot forth from the crater,
the brilliancy of which was visible even through the vapors. Thousands
of luminous sheets and barbed tongues of fire were cast in various
directions. Some, extending beyond the dome of smoke, dissipated
it, leaving behind an incandescent powder. This was accompanied
by successive explosions, resembling the discharge of a battery of
machine-guns.

Cyrus Harding, the reporter, and Herbert, after spending an hour on the
plateau of Prospect Heights, again descended to the beach, and returned
to Granite House. The engineer was thoughtful and preoccupied, so much
so, indeed, that Gideon Spilett inquired if he apprehended any immediate
danger, of which the eruption might directly or indirectly be the cause.

"Yes, and no," answered Cyrus Harding.

"Nevertheless," continued the reporter, "would not the greatest
misfortune which could happen to us be an earthquake which would
overturn the island? Now, I do not suppose that this is to be feared,
since the vapors and lava have found a free outlet."

"True," replied Cyrus Harding, "and I do not fear an earthquake in the
sense in which the term is commonly applied to convulsions of the soil
provoked by the expansion of subterranean gases. But other causes may
produce great disasters."

"How so, my dear Cyrus?'

"I am not certain. I must consider. I must visit the mountain. In a few
days I shall learn more on this point."

Gideon Spilett said no more, and soon, in spite of the explosions of
the volcano, whose intensity increased, and which were repeated by the
echoes of the