( 521 ) 



According to this table tlie increase of the amplitude when the 

 duration of the vibration diminishes seems to reach a maximum 

 value at 0.5 min. and moreover rhe ratio of amplitudes seems to 

 be dependent on the amplitude itself and in such a way that with 

 equal duration it increases with the diminishing of tlie amplitude. 



A complete confirmation of these results was found in 312 cases 

 for the Anjer-line. 



Batavia- Anjer. 

 Amplitude Earth-current in Volt p. K.m. 



Amplitude Magnetic Component in C. G. S. 



Here too with a short duration a maximum is found, viz. with 

 0.6 min. 



Beside this correspondence we find the unexpected result, that the 

 Batavio — Anjer curr^ent is about four times stronger than the Batavia 

 — Cheribon current. 



