The San Francisco Earthquake 



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The Seismograph of the U. S. Weather Bureau 



At 5 :i3 a. m., Pacific time, the city was 

 violently shaken for 28 seconds. The 

 force of the shock, as in 1868, was great- 

 est in that part of the city built on made 

 or alluvial ground (and probably heaved 

 by epifocal waves) and was sufficient to 

 completely wreck many large buildings 

 and to seriously damage most of the 



structures in the business section. Water 

 mains and sewers were broken, car 

 tracks were twisted, and at Eighteenth 

 and Valencia streets, not far from the old 

 Spanish mission, a crevice 6 feet wide is 

 reported to have opened in the ground. 

 At several points in the lower portions 

 of the city the ground is said to have set- 



