Though, therefore, there exists but little outward sign of the present activity of the internal fires which are still surely smouldering beneath the surface of the earth in this part of the world, and occasionally shake the mountain-piled continent from its foundation; the signs of their past power are such as to strike the observer with great wonder and awe.
To me the whole of the hollow valley of Mexico, with its ramparts of porphyric rocks, gave the idea of a vast crater, which had been, in ages of which no human tradition remains, the grand and principal vent through which the pent-up element, after, by repeated efforts, heaving up the continent step by step from its primeval level, finally escaped through the crust of the earth.
Would you accuse me of yielding too freely to the play of imagination, when I thought that I could read in the sublime features of the vast scene before me, the unrecorded history of past centuries; and faintly picture to myself the convulsions of which the valley around me must assuredly have been the theatre? At the time when the earthquake was bursting those innumerable fissures and barrancas which are observable in the surface of the lower districts; raising one sheet of level country after another to its ordained elevation; and sending up one long, towering range of porphyritic mountains after another from the abyss to the sky: how little can the fancy paint the scenes of awful desolation which must have existed here—the great combustion which may have given birth to the valley, with its basins of saline waters—and the successive formation and appearance of the numberless cones before me. The world has grown old, but the records of that age are fresh around us. What must have been the signs in the earth and sky, as the ungovernable and subtle element destroyed the unseen obstacles to its escape into the upper air, and the surface began to yield to the tremendous force exerted by the internal fires underneath. Here rose the huge pyramid, based upon the wall of the surrounding mountains; growing, day by day and year by year, by the accumulation of its own refuse, amid the showers of its own
