148 EARTHQUAKES ON THE PACIFIC COAST 



1890. March 15; SOh. 



Eoslyn, Washington, III. — P. 



1890. March 29; 14h. 30m. 



Eoslyn, Washing-ton, III.— P. 



1890. April 11; Ukiali; 11:30 a. m. (?). 

 Vibrations from southeast to northwest. 



1890. April 15; Mount Hamilton; 2:00 a. ni. 



No record except the tracing of the duplex seismograph, which is an 

 almost perfectly straight line running northwest and southeast. 

 The total actual displacement of the pendulum bob is 1.9 mm. 



1890. April 24; Mount Hamilton; 3:36 a. m. 



The duplex seismograph g-ives an exceedingly complicated tracing 

 in the general direction northwest and southeast The maximum 

 possible displacement of the pendulum bob was" 4.0 mm. in the 

 direction indicated above. 



At right angles to this the maximum displacement was 1.4 mm. 

 The tracing is folded on itself from nine to eleven times. 



1890. Mills Colleg^e; about 3:39 a. m. 



The tracing from the duplex seismograph indicates motion in every 

 possible azimuth. There is no marked tendency in any one direc- 

 tion. The maximum excursion of the pendulum bob is 11.1 mm. 

 running from north-northeast to south-southwest. By max- 

 imum excursion is here meant the maximum diameter of the 

 diagram. 



1890. Berkeley; 3:38 a. m. (Prof. Sonle). 



The tracing from duplex seismograph gives maximum displacement 

 (6.4 mm.) in a direction east-northeast and west-southwest. There 

 is quite a well-marked displacement of 4.3 mm. in an azimuth 

 which may be defined as " west-nortliwest " to " east-southeast." 

 The tracing recrosses itself from fifteen to twenty times. The 

 disturbance at Berkeley seems to have been considerably smaller 

 than at Mills College. 



1890. Cliabot Ob.servatory; 3:37:44 a. m. 



Duration six seconds; preceded by a rumble lasting ten to fifteen 

 seconds. General character and size of tracing from duplex seis- 

 mograph about the same as that observed at Berkeley. Maximum 

 double amplitvide of pendulum bob nearly east and west, amount- 

 ing to 5.7 mm. (Mr. Burckhalter.) 



1890. Kast Oakland; 3:37:40 a. m. 



Mr. F. G. Blinn reports the duration at ten seconds and the inten- 

 sity as (IV). The seismograph tracing is exceedingly compli- 

 cated, recrossing itself probably fifty times. The maximiim dis- 

 placement is east and west. 



