Page:Great Neapolitan Earthquake of 1857.djvu/302

From Wikisource
Jump to navigation Jump to search
This page has been validated.
248
SOUNDS HEARD HERE.

bably was—but they were all in great alarm." One or two considerable fissures had been produced in the new posthouse. I took observation of the sun here to determine the magnetic declination, and give the result as worked out, but am satisfied I must have committed some gross error in the observation or note of it.

Duchessa, Lat. 40° 34' N., Long. 15° 11' E. (Feb. 13)

Hour angle at time of observation = 24° 6' 48″.15
Sun's azimuth computed . . . . . . . = 27° 42' west.
Sun's bearing by compass . . . . . = 20° 0' east. (?)
Magnetic declination . . . . . . = 47° 42' east.

There is no ground for assuming any serious local disturbance of declination here.

From a little beyond Duchessa, off to the eastward, and rather to the south, Sisignano is seen perched upon a spur of Monte Alburno, that runs in a S.E. and N.W. direction diagonally across the main valley and down to the Tanagro. The road continues to rise rapidly, ascending over the shoulder of this, at the little village of Lupino, and to the south or right hand. The vast pile of limestone beds of the Alburno is seen stretching away with nearly horizontal strike, parallel to the general line of the great valley, and dipping sharply to the west and south-west, at probably 45°. The transverse ridge is too much covered to enable me to prove, what I conjecture from its outlines, that it consists mainly of the breccia limestone, unconformably laid on the beds of Alburno.

After about six miles, the highest point of the transverse ridge is reached, near Lupino, and I determined its height by barometer, which reads, at 1.32 Nap. mean time, 28.78