Page:Great Neapolitan Earthquake of 1857 Vol 2.djvu/203

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SITE OF VALVA—MAGNETIC DECLINATION.

movement here, which, had the shock generally been more powerful, would have left complicated traces of its action most difficult to decipher.

Valva stands nearly in the mid breadth of the valley, which, however sinuous, has so far had a general direction nearly east and west, but here is intersected by the larger and longer valley of the Salaris, which, before its junction with the Tanagro, runs nearly north and south, with many minor valleys, bringing its tributaries into the main river. The town of Valva, (a small place,) shows many old fissures of former earthquakes, but none of a measurable character from the recent one. The people whom I converse with, very generally state, that the direction in which they felt the great shock, was from the S.E. to the N.W., or a little more eastward of that, say 46° W. of north.

From the brow at the west side of the town, a very extended prospect is obtained; and I got several bearings for magnetic declination, which present very accordant results.

By Compass. Zannoni's Map. Declination.
Calabrita bears 26° W. of north 41° W. of north 15° W.
Coglietio 62° W. of north 76° W. of north 14° W.
Senarchia 76° W. of north 92° W. of north 16° W.
Crest of Monte Polveracchio „ 80° W. of north 96° W. of north 16° W.
Oliveto 134° W. of north 149° W. of north 15° W.
Contursi 149° W. of north 165° W. of north 16° W.
Mean magnetic declination, 15° 20' West.

The summits above Oliveto, probably those of Monte Negro, are hidden in clouds.