130 EARTHQUAKES ON THE PACIFIC COAST 



1889. April 17; 8:33:38 p. lu. 



Mount Hamilton: noted by J. M. Schaeberle, while observing the 

 colliniation constant of the meridian circle. The wii'es vibrated 

 through about 10 sec. Time noted, 8.32.40. Siispected in anotluT 

 part of the building- by J. E. K. Time noted, 8.32.3G. No per- 

 ceptible record on the seismographs (I). 



1889. April 17; lOli. 18m. p. m. 



San Francisco: a slight shock, E. to W. 



1889. April 20; 4 a. m. 



University of the Pacific, San Jose: Prof Higbie sends a record 

 obtained Avith his seismographs, showing a considerable distur- 

 bance. I have no other notices of this earthquake. 



1889. April 24; 3:37 a. m. 



San Francisco: " hea\\\ earthquake shock occurred at 3.37 a. m. 

 Vibrations from north to south." — Jenkins. Received at ^Vash- 

 ington Signal Office. 



1889. May 1. 



Lompoc: quite a heavy earthquake shock was felt here at 11.5.5 



to-day. The vibrations were from east to west. No damage. 

 Susanville: at 9 o'clock a sharp earthquake. The vibration was 



north and south. 



1889. May 19; 3:10 a. m. 



Central California: at the Lick Observatory nobody was awakened, 

 although the motion as registered by the seismographs was con- 

 siderable. This is probably owing to the long period of the 

 vibrations. The tiilie recorded by the earthquake clock was 3:9.6. 



The following letter was furnished by Prof. Holden to the Cali- 

 fornia Associated Press: 



Lick Observatory. — The earthquake was felt at the Lick Ob- 

 servatory at nine minutes past 3 o'clock this morning, as a series 

 of gentle shocks of small amplitude and slow period. It was not 

 severe enough to awake the sleepers. The extraordinary fea- 

 ture of this shock was its great duration, which is registered on 

 our instruments for no less than two minutes and twelve seconds. 

 In this feature it resembles the great Inyo shock of March 26, 

 1872, as experienced in San Francisco, and for a similar reason. 

 The observing station was in both cases far removed from the 

 origin of the shock, and the energy of the earthquake was mani- 

 fested in long waves of slow period, but lasting for an unusual 

 time. Moreover, in this case the shock w^as far more severe in 

 Santa Clara Valley than after it had traversed several ranges of 

 hills and reached Mount Hamilton. Our earthquake machine 

 shows that the up and down movement lasted eighty-four sec- 



