38. The granite mass, dislodged by the effect of the earthquakes, has left in some places fissures through which the melted substances have escaped: the volcanoes. The volcanoes are like chimneys to this immense furnace, or better still, like escape-valves, which, in providing an exit for the great excess of burning substances, preserve them from terrible commotions, whence one can infer that a large number of active volcanoes is a source of safety to the whole Earth.
One can form an idea of the intensity of this fire by learning how volcanoes opened in the midst of an ocean are not extinguished by the immense waters which cover and penetrate them.
