DAMAGE TO BRIDGES DURING EARTHQUAKES 



637 



There is a type of structure whose sensitiveness for recording earth 

 movements seems never to have been given its due weight, for we 

 look in vain for any grouping of the evidence from damage sustained 



Fig. I. — (A) Compressed railway tracks in the approach to the Kisogawa Railway 

 bridge after the Japanese earthquake of 1891 (after Milne and Burton). (B) Biwa- 

 jima Road bridge thrown into a serpentine form during the Japanese earthquake of 

 1891 (after Milne and Burton). (C) Car tracks which have sustained a sharp local 

 compression along an oblique intersecting line. California earthquake of 1906 (after 

 H. W. Fairbanks). {D) Electric railway tracks near San Francisco, showing a sharp 

 local compression along an oblique intersecting line. California earthquake of 1906 

 (after Moran). 



by bridges at the time of earthquakes. The writer has recently noted 

 in a brief .statement the rather common observation that the abut- 



