EAKTHQUAKES ON THE PACIFIC COAST 139 



1889. April 14; 7:2S p. m. 



Central California: Lick Observatory, time of ending 7.27.56 (E. S. 

 Holden), 7.2814 (E. E. Barnard). Felt by many persons at the 

 observatory, but not by all. Recorded on both seismographs 

 (III). 



The curve representing the north and south motion on the Ewing 

 seismograph begins with three quite regular waves of progres- 

 sively diminishing amplitudes, the period of each being 1.25 sec- 

 onds. The maximum (magnified) amplitude is 0.5 millimeter. 

 The east and west curve begins Avith a series of small, irregular 

 tremors, followed by two marked and fairly regular waves which 

 begin about where the waves of the north and south curve end. 

 Maximum (magnified) amplitude, 0.4 millimeter. The vertical 

 motion is very slight. The marked vibrations on all the curves 

 end at about ten seconds, but very slight undulations extend to 

 about one and one-half minutes. It is hard to say how much of 

 these is real. The intensity of this shock, computed from the 

 data above given, is 4.0 or (I) of the Rossi-Forel scale. 



San Jose, 7.27.30 (S. W. Burnham). San Jose, University of the 

 Pacific: the record on the duplex pendulum seismograph at this 

 place is considerably larger than that obtained at the Lick Ob- 

 servatory, and is very comj)licated. The San Jose Times says: 

 " The shock was not severe, but was quite plainly felt by many 

 people. A majority of people, however, were unconscious of any- 

 thing unusual." 



Santa Cruz: quite a severe shock, with quick, jerky motion from 

 east to west, rattling the windows in loosely built houses. Time, 

 7.25. Probably the heaviest shock felt in Santa Cruz in four or 

 five years, although many people on the first floor of well-built 

 houses did not notice it. — Santa Cruz Surf. 



An earthquake occurred at 7.30 p. m. The vibration was north 

 and south and lasted several seconds. — Dispatches from Santa 

 Cruz. 



Centerville: slight earthquake at 7.34. Vibrations northeast to 

 southwest. 



Los Gatos: two slight but distinct earthquakes at about 7.15. Vi- 

 brations from south to north. 



Gilroy: remarkably sharp but short earthquake at 7.25, making 

 lamps, crockerj', etc., rattle severely. 



Merced: a heavy double-shock earthquake at 7.33. Oscillation, 

 northwest to southeast, and about two seconds in duration. 



Oakland: earthquake at about 7.28, not felt by all persons. — F. G. 

 Blinn. The record on Mr. Blinn's seismograph shows about the 

 same amount of motion as at the Lick Observatory. 

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