Sparling, Earl: N. Y. World-Telegram (July 11, 1935), "Nikola Tesla, at 79, Uses Earth to Transmit Signals; Expects to have $100,000,000 Within Two Years" ~ Here Tesla tells the story of the earthquake generated by the mechanical oscillator in his NYC laboratory in 1898, which brought the police there to stop him. They entered the lab just in time to see Tesla swing a slegehammer and smash the tiny device, which was mounted on a girder:
Nikola Tesla revealed that an earthquake which drew police and ambulances to the region of his laboratory at 48 E. Houston St., New York, in 1898, was the result of a little machine he was experimenting with at the time which "you could put in your overcoat pocket."
The bewildered newspapermen pounced upon this as at least one thing they could understand and "the father of modern electricity" told what had happened as follows:
"I was experimenting with vibrations. I had one of my machines going and I wanted to see if I could get it in tune with the vibration of the building. I put it up notch after notch. There was a peculiar cracking sound.
"I asked my assistants where did the sound come from. They did not know. I put the machine up a few more notches. There was a louder cracking sound. I knew I was approaching the vibration of the steel building. I pushed the machine a little higher. "Suddenly all the heavy machinery in the place was flying around. I grabbed a hammer and broke the machine. The building would have been about our ears in another few minutes. Outside in the street there was pandemonium.
"The police and ambulances arrived. I told my assistants to say nothing. We told the police it must have been an earthquake. That's all they ever knew about it."
Some shrewd reporter asked Dr. Tesla at this point what he would need to destroy the Empire State Building and the doctor replied: "Vibration will do anything. It would only be necessary to step up the vibrations of the machine to fit the natural vibration of the building and the building would come crashing down. That's why soldiers break step crossing a bridge."
In another interview, he boasted that,
"With this principle one could split the earth in half like an apple".
Century Magazine, p. 921, Figure 2 (April 1895) ~ In 1893 Tesla constructed a preferred embodiment of the mechanical oscillator which he described as a "double compound mechanical and electrical oscillator for generating current of perfect, constant, dynamo frequency of 10 horsepower."
Allan L. Benson: World Today (Feb. 1912); "Nikola Tesla, Dreamer" ~ An illustration for the article shows an artist's conception of the planet splitting in two. The caption reads:
"Tesla claims that in a few weeks he could set the earth's crust into such a state of vibration that it would rise and fall hundreds of feet and practically destroy civilization. A continuation of this process would, he says, eventually split the earth in two."
New York Sun (July 10, 1935); "New Apparatus Transmits Energy - Tesla Announces Method of Remote Control," .
N. Y. American (July 11, 1935), Section 2; "Tesla's Controlled Earth Quakes Power Through the Earth, A Startling Discovery".
New York Herald Tribune (July 11, 1935), pp. 1, 8; "Tesla, at 79, Discovers New Message Wave - At Birthday Luncheon He Announces Machine for 1-Way Communication"
New York Sun (July 11, 1935); "Nikola Tesla Describes New Invention - Art of Tele-Geodynamics"
New York Times (July 11, 1935), p. 23, col. 8; "Tesla, 79, Promises to Transmit Force - Transmission of Energy Over World,"
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