A big thank you to Zdeněk Březa for alerting me to my error. Here is the correction.
BONUS
I have found an on line a source of the book “PRODIGAL GENIUS: - The Life of Nikola Tesla by John J. O'Neill (1944)”.
In his 1914 patent, he does not say sparks, he says
"A BALL OF FIRE MIGHT BREAK OUT AND DESTROY THE SUPPORT F or any thing else in the way. For the better ap preciation of the nature of this danger it should be stated, that the destructive action may take place with inconceivable violence."
Nikola Tesla was in Colorado Springs from May 1899 to January 1900. From his Colorado springs notes taken from the book above.
"Colorado is a country famous for the natural displays of electric force. In that dry and rarefied atmosphere the sun's rays beat on objects with fierce intensity. I raised steam to a dangerous pressure, in barrels filled with concentrated salt solution and the tinfoil coating of some of my elevated terminals shriveled in the fiery blaze. An experimental high tension transformer, carelessly exposed to the rays of the setting sun, had most of its insulating compound melted and was rendered useless. Aided by the dryness and rarefaction of the air, the water evaporates as in a boiler, and static electricity is generated in abundance. Lightning discharges are, accordingly, very frequent and sometimes of inconceivable violence. On one occasion approximately 12,000 discharges occurred within two hours, and all in the radius of certainly less than 50 kilometers [about 30 miles] from the laboratory. Many of them resembled gigantic trees of fire with the trunks up or down. I NEVER SAW FIREBALLS, BUT AS A COMPENSATION FOR MY DISAPPOINTMENT I SUCCEEDED LATER IN DETERMINING THE MODE OF THEIR FORMATION AND PRODUCING THEM ARTIFICIALLY."
NOTE: His description appears to recognise that nature produces static electricity in a similar way to the Armstrong Electrostatic boiler, a device he must have known about given his focus on the subject of static electricity. The principle of this device is what I proposed (after a tip off by David Boutilier) as being responsible for charge separation in the Thunderstorm Generator. As an aside, for builders of these kind of boilers, it should be noted below, in the nozzle images I have reproduced, the extreme turbulence and friction present in the steam path and the electrically insulating wood present in the nozzle designs.
In my Zurich presentation, based on a video of the TSG showing in my view coherent matter travelling waves (ejecta from ball lightning), similar to those witnessed in 3rd party attempts at GEET reactor builds, I believed it was based on ball lightning and that, if true, proof would come in the form of iron-rich crenellated microspheres.
These structures were subsequently and easily found in a sample of TSG that ran for 500 hours.
Tesla claimed to have learned how to produced balls of fire, He knew he was producing large amounts of static electricity and said he could produce balls of fire artificially and so probably knew the geometries that did result in them and how to avoid that. Tesla clearly chose his words and imagery very carefully, he knew the difference between a spark and a fireball, it the patent, he specifically said fireball, not spark.
Wonderfully, Tesla wrote short patents. When you write something short, you choose your words VERY carefully because they will be there for all time. As established above, he knew the difference between spark and ball of fire, he had established how to make fireballs before the patent was written and clearly separated the lightning discharges that he saw in Colorado from the fireballs he did not see but learned how to make, in his own prior words. He meant what he said, and it logically explains his expectation that it would destroy the support F. Recently we have seen photographic evidence showing how exploding ball lightning can push wooden buildings apart, so we know that it would destroy the support F.
Therefore, I conclude that he was talking about the risk of a “ball of fire” being synthesised and exploding and not a spark discharge. Moreover he stated in his patent that non perfect hemispherical inclusions should be in the toroid to bleed off excess to prevent the production of a “ball of fire” and its associated danger.
Here's the link I mentioned in the YT comment:
https://teslauniverse.com/nikola-tesla/articles/teslas-tower-wardenclyffe
The article on this website was taken from Electric Spacecraft Journal, April, 199, Page number(s): 13-22, in which the author pointed out:
By studying the periodicity of lightning beats at Colorado Springs, (see Figure 2), Tesla uncovered a phenomenon he called earth resonance. Indeed, there is some evidence that lightning is capable of producing earth resonance as Tesla described it. He explained that electrical impulses of sufficient magnitude travel longitudinally through the earth to the antipode and are reflected back. Mainstream scientists did not accept Tesla’s concept of longitudinal electric waves, and this is still very much the situation today.
In addition to discovering that the earth could resonate and carry electrical impulses, Tesla had learned years earlier that air, normally a good insulator, becomes an excellent conductor at high frequencies and voltages if reduced to about 75 mmHg. These facts indicated that the earth and its upper atmosphere could comprise a giant capacitor for high-voltage currents.
In order to utilize the earth-air capacitor, however, it seemed an antenna fifteen miles high was needed to connect to the upper air conducting layer. Tesla resolved this difficulty after further experimentation led to the development of a means of producing voltages three to four times greater than those previously created. Such electric forces, Tesla discovered, were capable of carrying current through much denser air.
Tesla was granted Patent #645,576, (filed in September, 1897), which acknowledged the feasibility of using lower atmospheric strata to conduct currents. The height of the transmitting towers need only be considerably taller than nearby structures to avoid unwanted discharges.
Tesla planned to apply his idea of earth electrical resonance to send electric power freely worldwide. Antennas placed anywhere would be tuned to receive the transmitted energy. The resonating longitudinal electrical impulses were to be transmitted through the conducting earth and atmospheric strata. To accomplish this Tesla knew he needed to create a substantial oscillation.
Wardenclyffe was to be the oscillator, *but Tesla insisted the resonant waves it was to transmit were longitudinal, not Hertzian*. (Current scientific thinking utilizes the concept of Hertzian waves in the form of Schumann resonance.) Wardenclyffe was to generate and send electric pulses to its dipoles, one of which was the top air terminal and the other, planet Earth.
So, C is the primary coil, A is the secondary drawing its current from the ground, B is the tertiary - a tightly wound coil acting as a cylinder over which a cold electric current was to flow and be amplified until it reached point D'. B' was then a column comprised of tightly bound parallel copper columns that splayed out at D' to form a hood, H. This was to carry the electron current resulting from the cold electricity hitting the hood (which also collected the e-m current and slow moving electrons making their way "the long way" around the copper windings to bring the whole to flat plate V). Flat plate V was totally electrically isolated from the torus D. The torus was covered in Aluminium cups P to increase the surface area, with some cups being larger than others to accommodate radiating away excess electrons to free space around the dome. It can be envisaged that the cold electricity, in particular, when hitting the flat plate V would cause a shower of electrons to pour out over the torus D, with the large Aluminium cups being used to radiate off excess electrons as a "safety valve". At the top of the cycle, with the D torus covered in electrons, the propensity of electrons to grab hold of aether would cause a stream of aether to pulled in toward the now collapsing electron source in the centre at plate V, causing a downrush of cold electricity down the central column .
Now, what the diagram does not show (although it is shown in other diagrams) is that the central column around which the tertiary B is wound descends deep into a shaft dug into the Earth to a depth of 120 feet, with radial horizontal “blackened” subterranean tunnels being present at the base of the shaft, to create an upside down ground antenna, with its base at point D'.
So, it almost looks like Tesla first drove electrons (and cold electricity) up into the virtual centre of the Torus in one cycle, and then let the whole collapse back down the central column, pulling aether in "from the sky", leading to the whole reaching the tip of the upside down antenna to radiate outward through the tunnels - and then, a short time later, to pick up the reflected waves to feed back up the column to see the cycle repeated.
In fact, it is operating somewhat like a piston driving electrons/cold electricity first up the column (using the Tesla transformer) and then pulling them back down the column (using the aether stream being pulled in through the Aluminium-cup-coated torus at the top of the tower)
In this way, a LONGITUDINAL WAVE resonant circuit was formed.
From the same article:
On May 16, 1900, Tesla filed for Patent #787,412 and further stated:
...powerful electrical oscillations communicated to the ground ... cause vibrations to be propagated to distant parts of the globe, whence they are reflected and by interference with outgoing vibrations produce stationary waves the crests and hollows of which lie in parallel circles....the planet behaves like a perfectly smooth or polished conductor......transmitting slow electrical oscillations without sensible distortion and attenuation.
...to establish the resonating condition...the earth’s diameter should be an odd multiple of the quarter wavelength.
...employ oscillations in which the rate of radiation of energy into space in the form of Hertzian or electromagnetic waves is very small.
...I would say the frequency should be less than twenty thousand per second, though shorter waves [higher frequencies] might be practicable...
...the wave train [frequency pulse] should continue for a certain interval of time...not less than...0.08484 of a second...which is taken in passing to and returning from the region diametrically opposite the [transmitter] pole...
It is worth noting that .08484 seconds is the time it takes to travel across the diameter of the earth and back at the speed of light.
Is this how he created the device that made earthquakes? By repeatedly discharging lightning into the earth from the piston like coils.