r is not always disastrous, and the island
had already undergone this trial, as was shown by the streams of lava
hardened on the northern slopes of the mountain. Besides, from the shape
of the crater--the opening broken in the upper edge--the matter would be
thrown to the side opposite the fertile regions of the island.

However, the past did not necessarily answer for the future. Often, at
the summit of volcanoes, the old craters close and new ones open.
This had occurred in the two hemispheres--at Etna, Popocatepetl, at
Orizabaand on the eve of an eruption there is everything to be feared.
In fact, an earthquake--a phenomenon which often accompanies volcanic
eruption--is enough to change the interior arrangement of a mountain,
and to open new outlets for the burning lava.

Cyrus Harding explained these things to his companions, and, without
exaggerating the state of things, he told them all the pros and cons.
After all, they could not prevent it. It did not appear likely that
Granite House would be threatened unless the ground was shaken by an
earthquake. But the corral would be in great danger should a new crater
open in the southern side of Mount Franklin.

From that day the smoke never disappeared from the top of the mountain,
and it could even be perceived that it increased in height and
thickness, without any flame mingling in its heavy volumes. The
phenomenon was still concentrated in the lower part of the central
crater.

However, with the fine days work had been continued. The building of the
vessel was hastened as much as possible, and, by means of the waterfall
on the shore, Cyrus Harding managed to establish an hydraulic sawmill,
which rapidly cut up the trunks of trees into planks and joists. The
mechanism of this apparatus was as simple as those used in the rustic
sawmills of Norway. A first horizontal movement to move the piece of
wood, a second vertical movement to move the saw--this was all that was
wanted; and the engineer succeeded by means of a wheel, two cylinders,
and pulleys properly arranged. Towards the end of the month of September
the skeleton of the vessel, which was to be rigged as a schooner, lay
in the dockyard. The ribs were almost entirely completed, and, all the
timbers having been sustained by a provisional band, the shape of the
vessel could already be seen. The schooner, sharp in the bows, very
slender in the after-part, would evidently be suitable for a long
voyage, if wanted;