The Days of a Man 1906 



time; the aggregate vertical displacement, as shown 

 by the rock strata on either side, exceeds half a mile, 

 although in the last two outbreaks there has been no 

 change of level on either side. In 1906, displacement 

 was purely horizontal, the west side moving north- 

 ward a distance ranging from about one foot in Mon- 

 terey County to twenty-four in Mendocino. From the 

 Lava rift in past eras masses of molten rock have flowed 

 dykes out . ser p en tine, basalt, and black lava appear at 

 intervals from San Francisco southward. Such out- 

 flows, being harder than the bordering sandstones, 

 heal the tear in a fashion, so that each succeeding out- 

 break occurs a little farther west. 



Within a few days, accompanied by Mrs. Jordan, 

 I started out to trace the new crack southward from 

 Tomales Bay near its northern limit on land 

 and to secure a goodly number of photographs. 

 During this process one came to have some under- 

 standing of primitive psychology, for it was difficult 

 not to think of the general devastation along the 

 sinuous line as the trail of a monster bent on destruc- 

 shock in- tion. As a matter of fact, however, the event must 

 neouTfor ^ ave k een instantaneous for the whole 192 miles, and 

 192 miles the damage wrought throughout was greatly aggra- 

 vated by the interference of waves spreading from 

 every point in the total length of the rift. These 

 augmenting, neutralizing, overriding, and otherwise 

 modifying one another, the final result was a violent 

 twisting motion, the most remarkable feature of the 

 disturbance. The belt of destruction extended from 

 twenty to fifty miles on either side, with gradually 

 diminishing effect. At Stanford we are about four 

 miles from the fault which lies along the base of the 

 Sierra Morena. 



C 182 3 



