312 STEPHEN TABER 



redwoods (Sequoia sempervirens) that had their tops snapped off 

 75 or loo feet above the ground. The intensity of the shock was 

 much less at this point than near the Hne of fracture, but the redwood 

 is brittle compared with the oak. 



Frame houses, strongly built and having good foundations, stood 

 the shock well, even when close to the fault-line, but brick and stone 

 structures were badly damaged at distances of more than 12 miles 

 from the fracture. Fortunately for the inhabitants, most of the 

 houses near the fault-line were one-story frame buildings. 



Most of the water-tanks that stood within 3 or 4 miles of the 

 fracture were thrown down, but farther away the percentage of tanks 

 that are standing gradually increases. With but few exceptions, 

 all brick chimneys within 3 or 4 miles of the fault-line were thrown 

 down, but at a distance of 8 or 9 miles probably more than 50 per 

 cent, are still standing. 



Within the area under discussion the earthquake seems to have 

 consisted of two separate and distinct kinds of movement: one a 

 violent vibration in a northwest-and-southeast direction, parallel to 

 the fracture, and probably caused by the sudden displacement; 

 the other a wave-motion, traveling at right angles to the fracture and 

 generated by the rocks slipping past each other along the fault-line. 



It was the first motion that snapped off branches, overturned 

 oak trees and wrecked buildings in the immediate vicinity of the 

 fault-line; and although this motion extended for a considerable 

 distance, the damage it caused was limited to a belt not over a mile 

 distant from the fracture. 



The following facts appear to bear out the theory of a violent 

 initial movement parallel to the fault-line. Most of the trees that 

 were overturned fell toward the northwest or southeast, and the 

 buildings that were destroyed near the hne of fracture tended to 

 move in the same direction; but frame buildings do not furnish 

 very rehable data. Beds and furniture rolled back and forth in 

 directions parallel to the vibration. The strongest evidence is fur- 

 nished by the movement of liquids, such as milk and water. In 

 the immediate vicinity of the fracture many places were found where 

 the water had splashed out of reservoirs and tanks on the northwest 

 and southeast sides, and at one place the motion had been so violent 



