Page:Great Neapolitan Earthquake of 1857.djvu/488

392 of north; and although very wide in limit, and often perplexed, from the complicated movements to which this place had been subjected, all were confirmatory of the general wave-path obtained at the Francescani already given.

The most instructive fissures I found, were those by which the two great gable walls of the refectory had parted off from the ends of the semicircular vault which formed the roof. An interior Photog. of this noble hall is given (No. 229, Coll. Roy. Soc.). The soffit of the vault was fissured in a north and south direction from end to end nearly, and half to one inch wide.

The gables were great semicircular walls of rubble stonework, run up from the chord-line or level of the springing, after the vault had been turned, and merely closed in against the ends of the arch, as in Fig. 239, not being bonded into it. Each of these gable walls had gone out at top from the end of the vault, producing a gradually widening and tremendous fissure, which, at the north end, was open 5 inches at top, and at the opposite, or south end, 3 to $3 1⁄2$ inches.



The gables, thick, heavy, inelastic, and yielding, from the bad rubble of which they are built, had bent over from above the chord-lines, showing innumerable minor thread-like fissures of dislocation in the work, more or less horizontal; neither had approached within some inches of the