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The directions and distances from Batavia are : 



Batavia— Anjer W 5°N. 



Laboean W 12 S. 



Serang W 4 N. 



Rangkas Betoeng W 17 S. 



„ Tangerang W IS. 



Bekassi E 17 S. 



Krawang E 14 S. 



I think it necessary for a better understanding of the results to 

 be mentioned hereafter, to summarise the results obtained before. 



In my former work on earthcurrents I always compared the 

 oscillations shown in the intensity of the current, with those occur- 

 ring simultaneously in the magnetic component, always taking into 

 account the horizontal component directed perpendicularly on the 

 straight line connecting the two stations. 



I measured the variations of the magnetic component in absolute 

 measure, and determined those of the earthcurrent by means of the 

 differences of potential per Kilometer, which, if existing, should give 

 the same variation of the current through the wire as was shown 

 by the recording galvanometer. 



Thus I did not decide whether such a difference of potential really 

 existed at the two stations. 



The records obtained brought to view the fact, that especially for 

 places one of which lies to the East of the other, each oscillation of 

 the earthcurrent corresponded with a simultaneous one of the component. 

 But if one station lies to the North of the other the correspondence 

 with the E.-W. component of magnetic force was much less than 

 in the former case. 



The connection between corresponding oscillations of earthcurrent 

 and magnetic force may be described thus. Those of the earthcurrent 

 precede those of force with a certain difference of phase; their 

 amplitude increases compared with those of force, when the duration 

 decreases. 



As to the amount of this difference of phase and of this increase 

 of amplitude I found them to be quite different for the coast-plains 

 of North-Java and the volcanic regions in the southern part of the 

 island. 



In the South especially the increase of amplitude, which accom- 

 panies decreasing duration, was much more rapid, than in the northern 

 regions. The following figures will make this divergence evident. 



