﻿16 C. G. Rockwood, Jr. — American Earthquakes. 



shock followed, and after another ten minutes a third was felt, 

 which was followed later by two more slight shocks. The sea was 

 extraordinarily agitated and the agitation continued with dimin- 

 ishing intensity through the 12th. 



Dec. 18. — h 30 m , a very light shock (III) at Tatoosh Island in 

 the extreme northwest of Washington Territory. It lasted about 

 five seconds and was followed by a second shock about ten min- 

 utes later. — XI. 8. Weath. Rev. 



Dec. 18. — At Amatitlan, Guatemala, a place of about 5,000 in- 

 habitants, situated twenty-four miles south of the city of Guate- 

 mala, slight but frequent earthquakes occurred, continuing all 

 day from 2 h to 17 h 22 ra when a heavy shock was felt. At 17 h 36 m 

 the heaviest and most destructive shock (IX) came, throwing 

 down many walls and houses already fissured by the earlier 

 shocks ; people were thrown down and the air was filled with the 

 dust from the fallen adobe houses. One hundred and thirty-one 

 shocks were felt the first day, principally from east to west, 

 eighty-one of which occurred between 16 h and 17 11 36 m . The 

 second day was nearly as bad, and the shocks continued for some 

 days subsequent. A government commission, consisting of Pro- 

 fessor Rockstroh and Mr. Walker, visited the place and reported 

 the total destruction of the village of San Vincente Pacaya and 

 an increase in the amount and temperature of the water emitted 

 by the hot springs about Lake Amatitlan, but no increased, ac- 

 tivity in the volcano of Pacaya. 



Dec. 28. — Between 3 h and 4 h , at Santa Cruz, California, two 

 light shocks of earthquake (IV) ; the vibrations were north and 

 south. — XI. S. Weath. Rev. 



Dec. 28. — 19 h 5 m , a loud explosion accompanied by a rumbling 

 sound and a very light earthquake shock (III) occurred at 

 Bloomington, Illinois. 



Dec. 29. Between 4 h 30 m and 5 h 30 m some very light shocks 

 (III) were reported at Hartford, Connecticut. 



Dec. 30. — 9 h 46 m , a moderate earthquake (V) was felt in the 

 vicinity of the bay of San Francisco. It extended from Red- 

 wood City and San Mateo on the south, to Napa and Petaluma 

 on the north, and inland to Port Costa and • Martinez, Contra 

 Costa County. At San Francisco it was preceded by a very light 

 shock, and the main shock lasted ten seconds with a north-south 

 motion, but here it was not very generally noticed by people in 

 the open air. At Oakland the duration was six seconds, motion 

 east-west, with a rumbling noise. At San Rafael houses rocked 

 and a loud noise was heard. At Petaluma and at Redwood City 

 the direction was north-south. This is the third earthquake in 

 this same district during the year ; the others were on January 

 26 and October 16. 



The above list for 1885 contains 71 items, not counting the one 



