STEADILY ALTERNATING CURRENT ON A LONG LINE. 341 



made to analyze these curves as yet, owing to the bad splash and 

 lumpiness transients they indicate. 



Splash Transient Occurring Singly. — If the line is made vir- 

 tually of infinite length with respect to the sending end, by ground- 

 ing it at B through an impedance equal to its surge impedance -sTq, 

 a splash produced by the closing of the line switch ofif zero e.m.f., 

 will give rise to a splash transient, that will vanish very quickly at 

 A; because no reflected waves can return from the distant end. 

 An example of this case is presented in Fig. 12 (Film No. 35). 



•Film. No,35. Line A. Endqrounded through 



Fig. 12. Non-recurring Splash and Casual Transients. 



Approximately the same half-length artificial line as in Fig. 11 

 (580 km.), is here grounded at B through a combination of resist- 

 ance and condenser, so as to produce an impedance, at 60.6'—', of 

 342.5 x' 4°. 4 ohms. The line switch was closed at a phase of about 

 20 electrical degrees later than the zero of ascending e.m.f. This is 

 seen to produce a splash both in Cs and is, the initial outgoing waves 

 of e.m.f. and current. This splash is also seen to be repeated in the 

 B-end voltage Cr, where the load (^0) is connected. The splash 

 gives rise also to a lumpiness transient, as may be seen by the ripples 

 in is, the entering current, during the first alternation. A similar 

 lumpiness ripple transient is faintly perceptible in the first alterna- 

 tion of e,- at B. Neither splash nor lumpiness transients are visible, 

 however, in the second or succeeding alternations in any of the 

 curves, these disturbances, according to theory, being all absorbed 

 at the B end, by the load Sq. 



Casual Transients. — At the point Aeg, Fig, 12, in the fourth 



PROC. AMER. PHIL. SOC, VOL. LIX, v, DEC. I4, I92O. 



