Ball Lightning & Tesla's Electric Fireballs
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| Author | Leland I Anderson |
|---|---|
| Published | 1997 |
| Publisher | Tesla Book Company |
| Pages | 31 |
Ball Lightning & Tesla's Electric Fireballs is a short monograph by Leland I. Anderson, the electrical engineer, archivist and Tesla historian who founded the Tesla Society and edited the great part of the primary-source Tesla literature available in English. Running to 31 pages, it surveys the reported phenomenon of ball lightning, sets out the principal historical proposals for how it forms, and connects that literature to Tesla's own reports of producing electric fireballs with his apparatus at Colorado Springs. Library cataloguing records the monograph as a 1997 imprint of Twenty First Century Books of Breckenridge, Colorado (LCCN 99491546); it carries no ISBN, having been issued as a small-press pamphlet rather than a trade book.
The monograph also prints, for the first time, Chapter 34 of John J. O'Neill's 1944 Tesla biography Prodigal Genius, a chapter titled "Tesla Tries to Prevent World War II" that was cut from the published book.
Summary
Anderson's purpose in the monograph is documentary rather than theoretical. He assembles what the historical record actually contains: the long run of published observations of luminous spheres seen during thunderstorms, the small number of nineteenth- and early twentieth-century investigators who attempted a physical account of them, and Tesla's Colorado Springs material describing fireballs generated inside and around the streamers of his coils. The book is written for readers approaching the subject from the Tesla side rather than from atmospheric physics, and its value on this wiki is that it places Tesla's fireball observations in the context of the wider ball-lightning literature instead of treating them as an isolated curiosity.
The publisher's description presents the subject as one that has "mystified people for hundreds of years" but that can now be produced at will, with researchers beginning to close in on the mechanism. That framing should be read as the claim of the experimenters whose work the book reviews, not as a settled result: the production of luminous, persistent balls in high-frequency electrical apparatus is reported, but whether such laboratory objects are the same thing as the ball lightning seen in thunderstorms remains open.
Ball lightning and proposed mechanisms
Ball lightning — also called spherical plasmoids, foudre sphérique in French and kugelblitz in German — is the name given to luminous spheres reported during lightning storms, typically in association with cloud-to-ground strokes. As Anderson summarises the observational record, reported diameters run from roughly that of a tennis ball to that of a basketball, and reported lifetimes from a few seconds to several seconds. Witnesses describe the objects bouncing along the ground, drifting or floating in air, and occasionally entering enclosed structures; one of the familiar early depictions is a woodcut showing a lightning fireball coming into a barn.
Published accounts extend back some two hundred years, yet no mechanism of formation is agreed. Anderson is explicit that the explanation "is yet debated in the literature", and he suggests that part of the persisting disagreement over the phenomenon's properties traces to the inconsistency of the very earliest reports, which fixed contradictory expectations in later observers.
Two historical proposals are given particular attention:
- Heinrich Hertz (1883). Hertz observed that every strong initial lightning discharge leaves behind a cloud which is luminous — that is, the discharge channel does not simply extinguish, but leaves a glowing residue that persists after the stroke.
- Maximilian Toepler. Reporting on a detailed series of experiments and observations, Toepler concluded that ball lightning is to be attributed to the formation of a conductive gas channel following an initial lightning stroke, within which an invisible weak after-current flows. On this account, at the point where a cloud-to-ground discharge and the counter-stroke rising from the ground meet, an afterglow may form and appear as ball lightning. The ball disappears when the supply of current ceases, or when a second cloud-to-ground discharge occurs.
Both are proposals, advanced by their authors on the evidence available to them, and neither is presented here as established. What they share is the idea that ball lightning is not an independent object but the visible afterglow of a residual current in an already-ionised channel — an idea that bears directly on the laboratory case, where a sustained high-frequency source is available to feed exactly such a channel.
Tesla's electric fireballs
The reason the monograph belongs on this wiki is its Tesla material. In the course of the Colorado Springs work of 1899 Tesla recorded the appearance of small, persistent fireballs in the neighbourhood of his high-frequency apparatus. He regarded them as a nuisance and a hazard to the equipment before he regarded them as a phenomenon worth pursuing, and he noted that they appeared repeatedly rather than as isolated accidents. Tesla later claimed to have determined the conditions under which they arose and to be able to generate them deliberately — a claim he never accompanied with a published theory, which is precisely why the record he left has continued to be worked over by independent researchers.
That work is documented elsewhere on this wiki. Robert Golka rebuilt Tesla's magnifying transmitter at Wendover, Utah, specifically in order to attempt the production of ball lightning, his interest being that a self-sustaining luminous ball represents a confined plasma and therefore bears on controlled fusion. James F Corum and Kenneth L Corum, working from the Colorado Springs photographs and notes, argued that the arrangements Tesla actually used — in particular the surrounding of multiple resonators by a single primary, and the pointed wire added to the top terminal of the extra coil — are the features later coil builders had omitted, which is why fireballs were common for Tesla and rare for everyone else. Their paper Fireball Production from a Tesla Coil is the most operationally specific claim in this literature, in that it states conditions a builder can attempt to reproduce.
Anderson's monograph is the documentary companion to that experimental thread: it supplies the historical observations and the earlier proposed mechanisms against which the Tesla-coil results are to be judged. See also the "Ball lightning and fireball production" section of the Tesla Technology topic page.
Excerpt
The following passages are excerpted from the monograph.
- Ball lightning, spherical plasmoids, foudre sphérique, and kugelblitz are some of the names given to luminous spheres which are sometimes seen during lightning storms accompanying cloud-to-ground strokes. Their reported size varies from that of a tennis ball to a basketball and persisting from a few to several seconds. They bounce on the ground and sometimes float in air. Published observations have appeared in the literature for 200 years, but an exact explanation of the mechanism of their formation is yet debated in the literature. Some of the very early accounts have perhaps given rise to the current divergence of opinion about their properties. One familiar early woodcut illustration shows a lightning fireball coming into a barn.
- In 1883, Heinrich Hertz made an observation that every strong initial lightning discharge leaves a cloud which is luminous. Maximilian Toepler, reporting on a detailed series of experiments and observations, also concluded that ball lightning is attributed to the formation of a conductive gas channel after an initial lightning stroke in which an invisible weak after current occurs. At the point where a cloud-to-ground lightning discharge and a counter stroke from the ground meet, an afterglow in the form of ball lightning may occur. The ball disappears when the supply of current ceases or when a second cloud-to-ground lightning discharge occurs.
Related work on this wiki
- Leland I Anderson — the author; Tesla historian and editor of the Tesla Presents series
- Nikola Tesla
- Tesla Technology — topic overview, including a section on ball lightning and fireball production
- Robert Golka — rebuilt the magnifying transmitter at Wendover for ball-lightning research
- James F Corum and Kenneth L Corum
- Fireball Production from a Tesla Coil — the Corums' account of the coil conditions under which fireballs are reported