Jour. So. Coll. Vol. I PI. VIII. 



^f If Of 69 Sff /£> 



Diagram of Horizontal Motion of the Earth- 

 quake of May 8th 1886 (Tokyo). The motion 

 is magnified four times. The smoked glass plate 

 revolved once in 84 seconds so that the short 

 radial lines mark the successive seconds. 



r^' 



^^ 78 79 



N 



