237 [Blake. 



from the wall. Many articles were thrown over towards the west. It 

 is generally conceded that the shocks were less violent on the hills 

 than in the lower parts of the city. It would seem, also, that the 

 high, brick buildings bent and vibrated under the motion, and were 

 perhaps less injured in general, than the more solid and unyielding 

 structures. The shot tower was distinctly seen to sway back and 

 forth several feet. 



The earthquake was felt at about the same time, and in the same, 

 or even greater force at Santa Cruz, Watronsville, and San Jose. 

 Northwards, we have, as yet, no record of its effects beyond Sacra- 

 mento, Petaluma, and Tomales Bay ; eastward it does not appear to 

 have extended beyond the foot hills of the Sierra Nevada. It was 

 not felt at Grass Valley, in Nevada County, and at Sacramento the 

 shock was not heavy. It was felt at Stockton in considerable force, 

 but it did not extend to Los Angeles. It was noted at sea, about 

 twenty-five miles from land between Monterey and San Francisco. 

 It thus appears to have been comparatively local, and confined to the 

 Coast Mountains and the central part of the great Sacramento Val- 

 ley. 



Additional shocks were noted in the evening, one of them about 

 ten o'clock being quite strong, and one the next day at twenty-five 

 minutes of eleven, shook the buildings again in a disagreeable way. 

 Over eleven distinct shocks were reported from Santa Cruz, and they 

 have continued at intervals up to this time. On the loth, there was 

 a third or fourth strono; shakino;. 



It is worthy of note that recent accounts from Portland, Oregon, 

 show that Mt. Hood is in a state of eruption, but we have no im- 

 portant particulars. On the 9th of September last, when at the Mut- 

 tole Valley, Humboldt County, I noted a very peculiar, sharp, lateral 

 shock, apparently from the northAvest. A severe shock was expe- 

 rienced at Fort Humboldt and Eureka, on Sunday, Oct. 1, which 

 threw down nearly all the chimneys, and did other damage. It would 

 thus appear that we have a season of unusual earthquake activity. 

 Even so late as this morning, shocks were noted in San Francisco, but 

 were so slight as not to be generally oliserved. 



The extremely local character of an earthquake of such violence is 

 to me an interesting and suggestive fact, and I shall endeavor to as- 

 certain its geographical range with more precision. 



Preliminary Notice of some Opinions concerning the mode 

 OF Elevation of Continental Masses. By N. S. Shaler. 



The following notice presents a brief summary of some views as to 

 the nature of the forces by which continents have been elevated, 

 which were presented in a course of University Lectures delivered at 



