Page:Great Neapolitan Earthquake of 1857.djvu/139

Rh work, as not unusual in churches, the brick-work, although of so much less density, fell as one mass, with fractures of severance along the lines of junction of the two; and vice versâ, when the brick-work, as in a few cases, was beneath, and stone-work above, and when the latter was thrown, if it did not push the brick-work over in its fall, the latter remained comparatively unharmed.

The limit of flexibility of stone masonry exposed to earthquake shocks depends, to an immense extent, upon the flatness and superficial area of the beds of the individual stones, and the completeness with which "breaking joint" and "thorough bonding" are preserved in the setting.

When the masonry consisted of rounded, lumpy, quadrated ovoïds, of soft limestone, as already mentioned in the general description of the poorer and older towns, and of which the Photog. No. 63, of a part of Polla is an example, the whole dislocation occurred through the enormously thick, ill-filled mortar joints; and almost all buildings thus formed, fell together at the first movement, in indistinguishable ruin. In the Photog. No. 64 (Coll. Roy. Soc.) of Pertosa, a poor, but more modern town, the class of masonry was a little better, and, as may be remarked, the ruin less complete.

Where, as in a few examples observed, the masonry was of the best class (and such as would be so recognized in England), the buildings thus constructed, stood absolutely uninjured in the midst of chaotic ruin. Some examples of this will be found in the second part—none more striking than that of the Campanile of Átena, a square tower of about 90 feet in height, and 22 feet square at the base, in which there was not even a fissure, while all around nearly