ON SETSMOLOGICAL INVESTIGATIONS. 



45 



List, of Strong Shocks — continued. 



Date 



1906 Sept. 27, 

 10.47 a.m. 

 (14.41.30 

 G.M.T.) 



1906 Nov. 15, 

 M.S.T., 

 5.15 A.M. 



1908 Feb. 14 



1908 



1908 



1909 



May 14 

 11 p.m. ± 

 (8.32.30, ± 

 May 15, 

 G.M.T.) 

 Aug. 18, 

 2.59 A.M. 

 3.08 a.m. 

 5.27 a.m. 

 Oct. 28, 



P.S.T., 

 10.48 p.m. 



1909 



1909 



Place 



Intensity 



San Juan, Porto ' 

 Rico, Santo 

 Domingo, and 

 St. Thomas 



Socorro, New 

 Mexico 



Prince William 

 Sound, Alaska 



Near Yakataga, 

 Alaska 



Oct. to 

 Dec. 



Dec. 10, 



Local time, 



9.10 a.m. 



Eureka, 

 fornia 



Cali- 



II (?) 



II (?) 



N.W. California 

 and S.W. 

 Oregon 



North of Great 

 Salt Lake, 

 Utah 



Agano, Guam . 



II 



Remarks 



Duration 30 sec. Shock general 



throughout Porto Rico. Felt for 



a distance of 300 to 350 miles. 



Probably central near San Juan. 



(PR.) 

 This was the severest of a long series 



of shocks which began on July 2 



and lasted seven or more months. 



Probably felt over an area of 



100,000 square miles. 

 Cables broken in Valdez Fiord. 



Recorded at distant seismograph 



stations (M.) 



Area of the shock probably not 

 more than 200 or 300 square 

 miles. First shock did all the 

 damage. 



Duration 22 sec. The centre of the 

 shock was near Fortuna, Hum- 

 boldt Co., Cal. (near Eureka), 

 where chimneys were thrown 

 down and much plate-glass 

 broken. At Ferndale and Eureka 

 the shock was nearly as strong. 

 Probably felt over an area of 

 250,000 to 300,000 square miles 

 on land. Probably due to a slip 

 on a fault near Fortuna. 



Thirty or sixty shocks reported from 

 the old lake deposits just north 

 of the present Great Salt Lake. 



Two shocks, duration 22 sec. This 

 was a heavy shock and did very 

 serious damage to buildings in 

 Agano. Small fissures were made 

 in the ground and water spouted 

 out in places. These were near 

 high-water mark and were un- 

 doubtedly due to slumping and 

 vibrations. Surface waves were 

 also seen. Recorded at Manila 

 at 23.33.9 and at Honolulu at 

 23.29.7 G.M.T. This would put 

 the time at the origin, sup- 

 posed close to Agano, about 23.30 

 G.M.T. 



X. List of Destructive Earthquakes which have occurred in Peru, and 

 North Chile. By H. Hope-Jones, Esq., Lima. 



All entries in this list are, with the exception of eight, additional 

 to those found in the provisional list by Count Montessus de Ballore 



