ox THE AFTER-SHOCKS OF EARTHQUAKES. 



141 



The results contained in tlie nbove table are graphically repre- 

 sented in Fio-s. 24 and 25. Fig. 24 shews that the number of earth- 

 cpiakes at Ökawara ^vas a little less than that at Gifu, and that the 

 seismic frequencies at the two places did not synchronize in the occur- 

 rence of maxima and minima. Fig. 25 shews that the seismic 

 frerptencv at Gifu synclironized in the occurrence of maxima and 

 minima with that at Midori, l)ut that at the latter ])lar-e it was generally 

 less than half what it was at the former. 



Fr(^m the ahove we may conclude that the after-shocks wliich 

 Avere felt at ]\lidori were in the main the same as those felt at Gifu, but 

 that the latter place was mucli nearer to the princi])al centre of these 

 shocks than the former'; also that the shocks which were felt al 

 Ökawara had mostly proceeded from a centre ditt'erent from and less 

 active than that of the shocks at Gifu. 



Thtis it seems that the activity of after-.shocks at the principal 

 epi-focal tract was distinctly less than at the regi(^ns to its north and 

 south. Again, from wliat \ can infer from information or from my 



