372 L. MARTIN — ^ALASKAN EARTHQUAKES OP 1899 '|j 



At Sitka, 260 miles southeast of Yakutat, the great earthquake of 

 September 10 was sensible/* though rather slight. Bishop P. T. Eowe, 

 who was lying down, was among those who felt it. Dr. C. C. Georgeson, . 

 who was walking out of doors, did not. Sitka was near the outer limit 1 

 of the sensible shock in this direction, and from several towns near by, in I 

 southeastern Alaska, specific statements have been received that these * 

 earthquakes were not felt. 



Lake Chelan, Washington. — On the east side of the Cascade Moun- I 

 tains, in the State of Washington (latitude about 47° 50' north, longi- i 

 tude about 120° west), water waves were observed on Lake Chelan at the " 

 time when the tremors of the great earthquake of September 10 were 

 traversing the region. Lake Chelan is nearly 1,200 miles from Yakutat 

 Bay, Alaska (figure 1). The waves, observed on at least four points of 

 the coast of this long, narrow lake, arose at about 2 p. m.^^ on an other- 

 wise glassy lake, there being no wind. They rose 15 or 20 feet, driving 

 a boat ashore and lasting nearly two hours. 



The earthquake originated at Yakutat at 12.22 (about 1.40 on Lake 

 Chelan). Transmission would occupy ten to twenty minutes or more. 

 The seismograph at Victoria, British Columbia (figure 1), recorded this 

 shock at 1.45^® (equivalent to 1.59 at Chelan). The first waves were 

 noted "at about 2 o'clock.'^ 



The phenomena might, of course, be due to {a) landslides or {h) a 

 secondary earthquake. In the absence of evidence of these, there is no 

 particular reason to doubt that the weak tremors Avere in some way natu- 

 rally amplified in this long, deep, mountain valley, so that earthquake 

 water waves were caused. In the Lisbon earthquake of 1755 water waves 

 on lakes and ponds in England and on Loch Lomond, in Scotland, at- 

 tended the shocks and at an even greater distance than from Lake Chelan 

 to Yakutat Bay. 



Resnme of the great earth guahe of September 10. — This earthquake is 

 known to have been felt at more than forty places (figure 4), varying 

 in distance from 2 miles to 430 miles from the origin in Yakutat Bay. 

 Water waves were probably caused nearly 1,200 miles away. The obser- 

 vations include earth movement, faulting, water waves, floods, avalanches, 

 fissures, spouting from sand craterlets, difficulty in standing and walk- 

 ing, damage to buildings, a cemetery, etcetera, terror on the part of ani- 



7* The Sitka Alaskan, September 16, 1899 ; Seattle Dally Times, September 28, 1899. 



'5 San Francisco Chronicle, September 15, 1899 ; Salt Lake Semi- Weekly Tribune, Sep- 

 tember 19, 1899. Information obtained from C. E. Rusk, of Chelan, in 1909. 



^8 Interview with Mr. Napier Denison, the Government observer, in the Victoria Semi- 

 Weekly Colonist, September 21, 1899. Unfortunately this valuable seismograph was 

 subsequently lost in the mails. 



