THE NATURAL PERIOD OF LINEAR CONDUCTORS 



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means of experiment with two rods each equipped with a removable 

 thermocouple, to have no effect on the resonant frequency. With 

 two rods in proximity the resonance was much more sharp and definite 

 than for one rod, and was also more sensitive to effects producing 

 variations in the natural period. 



Three separate rods were used, their specifications being, 



WAVELENGTH IN METERS 

 Curve II — 300 cm. rod 



Curve I shows the maximum current versus height above ground 

 relation for the 300 cm. rod. The generator antenna was 2.55 meters 

 above ground and the horizontal spacing between generator antenna 

 and resonant rod always 7.7 meters, both antennas horizontal. The 



