CHAP, x.] ELECTRICITY AND MAGNETISM. 



377 



lines -of- force becomes a maximum. Hence, through all 

 its journey from E" to E' the number of (positive) lines- 

 of- force embraced by a strand of the coils has been 

 diminishing ; during its journey round the other half 

 from E' to E" again, the number will be diminishing. 



Fig- 153- 



Therefore, by the rule given in Art. 395, in all the coils 

 moving round the upper half of the ring direct currents 

 are being generated, while in the coils of the lower half 

 of the ring inverse currents are being generated. Hence 

 there is a constant tendency for electricity to flow from 

 the left side at E' both ways round towards the right 

 side at E", and E" will be at a higher potential than E'. 



