Page:Great Neapolitan Earthquake of 1857.djvu/420

334 hardness and sonoricity I had found in the flanking peaks of the Valley of the Tanagro, some twenty miles to the north.

Many isolated houses and other buildings about here, founded upon the deep clays of the piano, exhibit by their fissures, an almost completely uniform direction of wavepath north to south, and an angle of emergence so small as to seem almost zero. I observe, however, that wherever such buildings are founded upon the limestone rock, upon the gentle slopes, of the lowest hill sides of the east side, of the Vallone, the wave-path tends a little to the E. of north, i. e. it seems to come from the line of the eastern flank range, more or less, but still with the prevailing north to south path; the divergence towards a N. E. to S. W. direction being from 10° to 25°: and the angle of emergence, at once changes from nearly zero, to a pretty large one, but which gradually decreases as I travel south.

Within a mile of La Sala, on the left of the road, stood a square, strong-built house, which was perfectly cardinal, and afforded excellent measurements by fissures and thrown wedges. It gave a subnormal wave-path nearly 171° W. of north, and an angle of emergence of 24°. Another cardinal building to the right of the road just entering La Sala, shows a subabnormal wave-path 155° W. of north, and with nearly the preceding angle of emergence, the wave here again appearing to come from the line of the lateral range to the eastward.

Nearly opposite the town, I observe at a quarter of a mile out in the plain, several large haystacks (Fig. No. 197, Sketches Coll. Roy. Soc.) leaning over at top very much to the southward. They had their longer axes nearly