158 HOUSTOX, KEXNELLY — THE PATH OF A CURREXT. [Mar. 19, 



Fig. 1 6, represents the condition of affairs the moment after the 

 disappearance of electric flux. Here the electric flux has reap- 

 peared in the form of the two metre blocks, which take their depart- 

 ure towards the centre of the line, but now it will be observed, by 

 the direction of the flux arrows, that the electric flux is reversed in 

 direction. Consequently, the lower wire has become positive and 

 the upper wire negative ; or, the 500 volts difference of potential 

 between the wires is reversed in direction by reflection from the 

 short circuits at the termini. The magnetic flux possesses its 

 original direction as shown by the curved arrows. Consequently, 

 the momentary current, which is constituted at any point along the 

 line by the flux rush past it, does not change direction when the 

 pulse comes back reflected. 



The two reflected metre flux-blocks rush with the speed of light 

 towards the centre of the line. The condition of affairs just before 

 they meet is represented in Fig. 17. The magnetic flux is oppo- 

 sitely directed in the two blocks. Consequently, when the two 

 blocks merge, as shown in Fig. 18, the magnetic flux is annulled, 

 but the electric density is doubled. We have, therefore, in Fig. 

 18, 1000 ergs of energy in electric flux, situated in a metre block, 

 but with the opposite direction of potential to that which exists in 

 the original state of Figs. 4 and 5. 



F19. 17 



m m m m 





m m m' m' 



Fi^. 18 



Fig. 19 





^^ r-w^y ^mttn^ •■>• 



'in m m' m' 

 FlGS. 17-19. — Collision, of Reflected Electric Flux Waves in Circuit of Perfect 

 Conduction and Insulation Short-Circuited at Termini. 



'The two metre blocks then separate out by passing through each 



