328 SEE— THE CAUSE OF EARTHQUAKES. [October 19, 



have been undeniable oscillations of the land, similar to, but on a 

 larger scale, than those observed during the historical period. 



6. Conclusive proofs of the upheavals of the Chilian coast during 

 the earthquakes of 1822, 1835, etc., have been given by Lyell, and 

 will not be repeated here. We content ourselves, therefore, with the 

 following account of the Valparaiso earthquake of August 16, 1906, 

 which speaks for itself : 



The Great Earthquake at Valparaiso, August 16, 1906. 



A special copyrighted cablegram to the San Francisco Examiner of 

 August 22, dated Valparaiso, Chili, August 22, says : 



" The recent seismic disturbances in this region have thrown up several 

 new islands in Valparaiso Bay. These islands are of various dimensions, 

 some being very extensive while others appear to be mere cone-like rocks 

 jutting above the waters. It is reported that islands have appeared at dif- 

 ferent points along the coast of Chili. . . . 



" The wrenching given the earth's surface is still showing more and more 

 day by day. In sections of the harbor and on the coast, the shore line has 

 been materially changed. Promontories have slid bodily into the sea and 

 in other places strips of coast line have been completely submerged. The 

 theory is that there has been a great uplift of the Ande§ so as to change 

 almost entirely the contour of the hilly region of the republic. Landslides 

 are everywhere in evidence. Mountain sides have been stripped away and 

 chasms in the hills filled up. 



" Persons who have arrived here on horseback from points along the 

 coast say that they witnessed nothing but devastation. Whole villages were 

 wiped out." ^ 



' Since this paper was finished. Professor H. D. Curtis, in charge of the 

 D. O. Mills Expedition of the Lick Observatory, at Santiago, Chili, has 

 written an interesting letter to Professor Kroeck of the Pacific University at 

 San Jose, which is published in the San Francisco Argonaut of November 3. 

 Professor Curtis says: 



" A Commission has been appointed to study the shock and its causes. I 

 published a statement that the primary cause was doubtless the same as at 

 San Francisco, the slipping or sliding of one stratum past another, due to 

 the well-known geological fact that the Coast of Chili is very slowly rising. 

 I learn since that the Bay of Valparaiso is now ten feet shallower. So I 

 think the displacement in this shock will prove to be mainly vertical. It 

 may be that the centre of disturbance was under the sea, as Valparaiso suf- 

 fered much more than Santiago." 



Professor George Davidson, President of the Seismological Society of 

 America, informs me that during the great earthquake at Yakutat Bay, near 

 Mt. St. Elias, Alaska, September 3-20, 1899, the land at the head of Yakutat 

 Bay was raised 47Vs feet. In the Bulletin of the Geological Society of 

 America, vol. 17, May, 1906, will be found a careful investigation by Tarr 



