Page:Great Neapolitan Earthquake of 1857.djvu/347

Rh sediment, it is obvious that that portion which passes through the subterraneous channel is filtered, or at least deposits much of its solid material on the passage, and is no doubt now forming new and strangely situated beds of clayey limestone, within the cavernous heart of the mountain range through which it passes, and which here separates, as by a huge wall, the valley of the Tanagro, from the Piano di Diano.

A short way within the cavern is a shrine of wood, with a rude plaster figure of St. Michael, of about three feet in height, in the interior. I found this 'genius loci' had been overthrown by the shock, and as the shrine is fastened up like a sort of cage, the figure was still leaning supine, against the back of the box at a slope of about 30° with the vertical. The saint had fallen, in a direction from W. towards the E. The base of the image projected widely in front, but less at the rear, and the figure being of a very upright character, it had been thrown over by the first movement, to an angle beyond the range of recovery, by the return stroke of the wave, and so remained out of the perpendicular.

The velocity of the shock had been sufficient to upset the image, but had not been sufficient to overturn the square wood shrine or cage in which it was placed, and which was about 8 feet high and 3$1⁄2$ feet wide in the E. and W. direction. A sufficient corroborative proof, of the steepness of emergence of the wave here, is afforded by the stability of this shrine, near the top of which, was the stage on which the figure stood. An extremely small velocity, if horizontal, or nearly so, in direction, would have sufficed to overthrow the whole affair.