Nikola Tesla Books
[Sec. 5.b., cont.] Expressing these two time intervals as rational fractions, we have: 1/12 = 0.08333+ = 55/660 0.08484+ = 56/660 The lowest common denominator of these two fractions suggests that actual measurements may have been made with a time base corresponding to that number. For Tesla, the significance of this time interval in his concept for the establishment of standing waves in/on the earth lay in the necessity for a wave train continue a sufficient time in order to provide reinforcement of the reflected waves. A generated wave train must continue for as long as it would take the wave front to propagate to the antipode, effectively along a diameter, and be reflected back to the origin.* Tesla estimated the minimum time as expressed above. Lightning does not produce wave trains of such a time interval. That is why Tesla was encouraged by the possibility of achieving what lightning could not achieve, and that is producing waves of sufficient persistence. The problem that confronted him was to be able to produce waves of sufficient intensity. He believed that he achieved this by designing an oscillator (Magnifying Transmitter) that would be in resonance with the natural period(s) of standing waves in/on the earth. How did Tesla determine the necessary persistence time of approximately 1/12 second (-0% +1.8%)? James Corum has provided insight into this in his critical analysis of the CSN--Tesla possibly using the setup shown in the circuit diagram on page 180 of the CSN (Sept. 6, 1899 entry) as a "massive relaxation oscillator at ELF." Tesla was thus possibly able to generate current pulses exceeding 50,000 amp peak (cable was 5/8 in. dia), sufficient to excite the Schumann cavity in its first resonance mode with a relatively short stub antenna of 140 feet (See Sec.7.). * In the Tesla Patent No. 787,412, a disclosure is made on page 3, lines 59-62, that the mean propagation velocity of the generated waves over the earth's surface to and from the antipode is about 471,240 kilometers per second (292,830 mi/sec). Tesla rationalizes this illusory surface phase velocity of pi/2 times the velocity of light as a result of the "actual through-the-earth conduction" of the waves. He elsewhere refers readers to the writings of the famous astronomer-mathematician Thomas Jefferson Jackson See who also found the same constant for the apparent velocity of "etherons," the smallest particles of the ether. - 13 -
