1897.] HOUSTON, KENNELLY — THE PATH OF A CURRENT. 163 



and sideways into the conductor, as the blocks move on. Conse- 

 quently, the electric density and the accompanying magnetic 

 density are diminishing, but no straggling electric or magnetic 

 flux is left to mark the passage of the blocks. If the original stock 

 of energy was looo ergs, the energy which may reside in the two 

 blocks, when they reach the ends of the line, may be, perhaps, only 

 IOC ergs, depending entirely upon the amount of electric resistance 

 in the conductor, and the corresponding amount of leakage which 

 must be given to the insulator in order to balance the same. 



Fig. 26 



IMIlJUklMiJ ■ _^ 



f^ — — ■ — -.-,_. JtrsKtax. , — ■ — ., .. ... ~. — — - .. ., T\ 



F19.27 



-^ . ^jMuji^ Mmi\^ , ;7~" 



Fiq.28 





Figs. 26-28. — Movement of Electric Flux in Distortionless Cable. 



Fig. 28, represents the condition of attenuation without distortion 

 at the later stage in the process. 



We have hitherto assumed that only a metre block of electric 

 flux was started from the centre of the circuit, and that this was 

 called into existence in some special manner. We shall now con- 

 sider what takes place when an electric source, such as a dynamo 

 or battery, is connected permanently between the wires at one 

 end of the circuit. In Fig. 29, a dynamo is supposed to be con- 

 nected at the end A, the positive pole to the upper wire and 

 the negative pole to the lower wire. The dynamo is assumed to 

 have no resistance, and the distant end of the line is short-cir- 

 cuited at B. The moment the connection is effected, electric 



