( 785 ) 



DIFFERENCE IN PHASE 



So the diftereiice in phase is different for the two lines. Extra- 

 ordinary is here the increase of the difference in phase for the North- 

 line, which is not found on the other lines. 



Fornierlv was found for the difference in phase on the line 

 Seniarang — Batavia 36°. Whether the difference with the difference 

 in phase now found of 31° is real must still be called doubtful. 



These new results led to the conclusion that the difference in 

 character found formerly might not be attributed to the greater 

 distance, but to a peculiarity of the line itself. As the two lines 

 round the South and the North were between the same earth- 

 plates and possessed about the same resistance, I had to conclude to 

 an appearance of electromotive force in the line itself. There are 

 two possibilities for this : 



1^^ . induction immediately in the wire; 



2"^^. contact with the ground. 



Now it is very well possible that both causes ai-e very different 

 in the diluvial and alluvial plain of the Northcoast and the volcanic 

 Southern regions. 



To separate these two causes I have taken the following double 

 experiment. 



Batavia and Cheribon are connected by two parallel brass wires 

 of the intercommunal telephone ; there are likewise two telegraph 

 wires on the same poles between Batavia and Soerabaja. Such a 

 double line I connected with my galvanometer and switched on 

 between galvanometer and earth a resistance which was great com- 

 pared to that of the wire. (For Cheribon that resistance was 5000 

 Ohm, for Soerabaja 40.000 Ohm). I then left both wires connected 

 with the galvanometer for some hours and then broke off the con- 

 nection with one of the wires. 



After a few hours I switched this wire on again, but broke the 

 connection with the other one, and then finally I connected both 

 wires again. 



