Page:Great Neapolitan Earthquake of 1857.djvu/264

214 which had been shifted from its place by the momentum of the pendulum, as in Fig. 115.



I shall recur to the inferences derivable from this in Part III. It is sufficient here to remark that the direction of wave movement indicated is one approximately 6° E. of N. The clock was going (tempo meridiano) or solar time for Naples, and was on the evening of the 16th December true to time within an error of 0.5 second. It had been stopped at 10$h$ 13' 26" P.M., which was therefore the time of the first shock at Naples, within less than half a second the error of the clock (slow), + the minute fraction of time due to the increased semi-arc of vibration.

There were several other clocks, some with pendulums,