l Wednesday,
the first day of the dread disaster.
OFFICIAL RECORD OF THE EARTHQUAKE.
It is important here to give the official record of the earthquake
shocks, as given by the scientists. Professor George Davidson, of the
University of California, says of them:
"The earthquake came from north to south, and the only description I am
able to give of its effect is that it seemed like a terrier shaking a
rat. I was in bed, but was awakened by the first shock. I began to count
the seconds as I went towards the table where my watch was, being able
through much practice closely to approximate the time in that manner.
The shock came at 5.12 o'clock. The first sixty seconds were the most
severe. From that time on it decreased gradually for about thirty
seconds. There was then the slightest perceptible lull. Then the shock
continued for sixty seconds longer, being slighter in degree in this
minute than in any part of the preceding minute and a half. There were
two slight shocks afterwards which I did not time. At 8.14 o'clock
I recorded a shock of five seconds' duration, and one at 4.15 of two
seconds. There were slight shocks which I did not record at 5.17 and at
5.27. At 6.50 P. M. there was a sharp shock of several seconds."
Professor A. O. Louschner, of the students' observatory of the
University of California, thus records his observations:
"The principal part of the earthquake came in two sections, the first
series of vibrations lasting about forty seconds. The vibrations
diminished gradually during the following ten seconds, and then occurred
with renewed vigor for about twenty-five seconds more. But even at
noon the disturbance had not subsided, as slight shocks are recorded
at frequent intervals on the seismograph. The motion was from
south-southeast to north-northwest.
"The remarkable feature of this earthquake, aside from its intensity,
was its rotary motion. As seen from the print, the sum total of all
displacements represents a very regular ellipse, and some of the
lines representing the earth's motion can be traced along the whole
circumference. The result of observation indicates that our heaviest
shocks are in the direction south-southeast to north-northwest. In that
respect the records of the three heaviest earthquakes agree entirely.
But they have several other features in common. One of these is
that while the displacements are very large the vibration period is
comparatively slow, amounting to
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