CHAFFEE. — IMPACT EXCITATION OF ELECTRIC OSCILLATIONS. 



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ondary current, and, at right angles to it, the sum of the deflections 

 due to the primary and the second secondary currents. If, now, the 

 second secondary capacity be varied, there suddenly appears on the 

 fluorescent screen, as resonance for one of the harmonics of the primary 

 is obtained, a Lissajou's figure corresponding to the ratio of frequencies 

 of the two secondary oscillations. In addition to the simple Lissajou's 

 figure, which is due to the free vibration of the two secondaries, there 



