Nexus - 0802 - New Times Magazine-pages

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NEWSCIENCENEWSCIENCENEWSCIENCE ball lightning is actually fairly simple and enough information to appreciate what is A popular demonstration is depicted in easy to produce and that the inexpensive involved in the laboratory production of — the drawing, where a vacuum tube or a flu- apparatus needed already exists in many _ ball lightning. orescent strip light glows by itself when amateur enthusiasts' workshops and count- A glance at the accompanying illustra- held near the terminal due to the high lev- less college science departments around the _ tion shows that the Tesla coil consists of _ els of free electricity discharged in the air world. Predictably, perhaps, this is the two coils of copper wire wound around around it. Tesla coil. cylinders—one wide squat one, called the James Corum really put this previously- primary, and a taller narrow one which sits REINTERPRETING TESLA'S NOTES thought-of technological impasse into per- _ inside it, called the secondary. At the top So if the Tesla coil has been so freely spective when he commented that making — of the secondary is a brass or copper ball available around the world since it was ball lightning in the laboratory would make _ joined to the coil; and as can be seen from _ patented by Tesla in 1897, why has nobody an interesting high-school science project! the drawing, this is also the terminal from used it to produce ball lightning before Whilst such fireball production would be which spectacular high-frequency electrical now? beyond the layperson, students and amateur streamers are emitted when the device is in This issue is even more puzzling when it physicists who have specialised in explor- operation. is realised that Tesla himself frequently ing the intriguing inventions of the leg- In fact, the Tesla coil was specifically induced fireballs during his experiments. endary Nikola Tesla should certainly have constructed to produce such high-voltage He is quoted as stating: "I succeeded in enough technical information to put the discharges of microwaves, and it is within determining the mode of their formation required hardware together, given average these long streamers that the electric fire - and producing them artificially." In fact, electrical workshop resources. The appara- balls appear—and remain when the power the way he described them, they just tus used—the Tesla coil, many of which _ has been switched off. seemed to bubble readily from his coil have been built at home by electrical hob- These primary and secondary coils, apparatus. byists in their garage workshops—is a__ which are not physically connected to each The answer to this puzzle lies in the common feature of the physics departments other, are set within circuitry which _ incredible fact that Tesla's published notes, of many colleges and universities. includes various electrical units (termed a despite being studied by countless highly spark gap anda capacitor) designed to qualified physicists over the past hundred TESLA COIL BASICS pump up the power output to very high lev- years, have simply been misunderstood! For even the uninitiated, a basic descrip- _ els extremely quickly. For those with tech- Physicists have tried to copy Tesla's results tion of what the Tesla coil is and does is _ nical knowledge, peak power of 100 kW in and failed, putting such failures down to fairly easy to comprehend, and provides _10 microseconds is typical. his ambiguous notation style. The Carume a A popular demonstration is depicted in the drawing, where a vacuum tube or a flu- orescent strip light glows by itself when held near the terminal due to the high lev- els of free electricity discharged in the air around it. apparatus. The answer to this puzzle lies in the incredible fact that Tesla's published notes, despite being studied by countless highly qualified physicists over the past hundred years, have simply been misunderstood! Physicists have tried to copy Tesla's results and failed, putting such failures down to his ambiguous notation style. The Corums relate that after taking part in an International Tesla Symposium at Colorado Springs, where Tesla's laboratory remains, they were on the plane flying home to Cleveland: "It was a puzzle to us ... we continued to compare chapter 34 with the photographs in Tesla's published notes. And then it struck us. We just weren't using the circuit con- figuration which Tesla shows us. When we got back, we rearranged our apparatus..." TESLA COIL BASICS For even the uninitiated, a basic descrip- tion of what the Tesla coil is and does is fairly easy to comprehend, and provides THE CORUMS' RECONSTRUCTION Intriguingly, the Corums then go on to describe what happened: "Small points of light seemed to appear from nowhere, then several of the floating lights were struck by high-voltage stream- ers emanating from the terminal of the sec- ondary coil. "Suddenly we observed multitudes of fireballs with diameters ranging up to sev- eral centimetres which were 'born' within the streamers emitted by the coils ... life- times typically ranged from one-and-a-half to several seconds... "A wide range of colours [was] produced ... in a manner similar to the presence of flare compounds in pyrotechnics. The demise of some fireballs [was] often 48 - NEXUS FEBRUARY — MARCH 2001