Page:Great Neapolitan Earthquake of 1857 Vol 2.djvu/187

128 a mile in length, its sides are not above 100 to 200 feet across, jagged and saw-like, the salient and re-enterant angles, and even the opposite beds, (whose strike is very generally transverse to the great chasm,) corresponding, and everywhere presenting evidence of actoal fracture; the mural precipices to the west side frequently 500 to 700 feet in height, above the torrent bed.

This great line of dislocation, is joined by others at several points, at angles more or less acute; so that both Bella and Muro, stand upon spurs having chasms of dislocation at two sides, the former between those of the Carpineto and the Fumarella, the latter between those of the Giacojio and the Malde.

On examining Figs. 1 and 3 it will be seen, that the bifurcation of these chasms, in relation to the general wave-path at each place, is such, as to interpose the breadthway of the dislocations, filled in with loose material, dropped down between their rigid jaws, between the towns and the advancing shock; and to this condition must be attributed, the almost entire immunity from injury, that they have experienced. Situated, both on solid limestone, with free lying surfaces opposed to the direction of wave transit, and at no enormous distance, from towns which were totally destroyed, these must have likewise perished, had it not been, that these deep trenches, broken up by nature, and loosely filled in with a compressible cushion, of boulders gravel clay and such-like loose materials, had stood like great bufiers, to receive the shock of the wave, and destroy at once, to a great degree, its velocity and its further propagation, by compression of the filling material between the jaws of these profound chasms. A new and unexpected