Original poster: "Derek Woodroffe" <tesla@xxxxxxxxxxxxxxx>
"On of my friends, whose wife doesn't mind foul smells, used to produce
little fire balls from his TC by putting on his HV terminal a piece of
rubber insulation stripped off a wire, lighting it, and firing up. I have
some pictures somewhere. Many others have used similar methods. I can't
get away with that sort of thing around here, only dangerous experiments
which aren't so obvious!
Ed"
As has been mentioned there appears to be two (at least) types of ball
lightning. This sooty type appears to be the easiest to reproduce. I have
produced a small, intensely bright short lived sphere of plasma from a
lighted candle on top of a small tesla coil. This (I assume) has the same
starting ingredients as a lighted toothpick in a microwave, plasma, carbon
particles (soot or similar) and pumped with RF. Although mine didn't break
away from the breakout.
As the Ball requires a large constant RF source to keep the effect running,
I doubt that it is the same process that is going on with a natural
lightning created ball. This is assuming that in larger lightning balls
there isn't some internal mechanism to prolong the RF field. In all cases of
this type of "sooty" ball, removing the RF field caused the ball to collapse
instantly and soundlessly unlike many of the eyewitness accounts.
The balls created by shorting high currents e.g. welding also (again I
assume) contain a plasma, and would have been created in a high RF (magnetic
or electrical) field. What I can't see is the (carbon?) substrate required
in "sooty" ball lightning, unless the vapour of the ablated metal counts.
So this leaves the "real" ball lightning, I suppose you could argue that is
it the same "type" as the two above, but with much higher powers, but again
the observation of the ball passing through doors, if it is to be believed,
negates the possibility of there being a material core. Other that that most
of the stories have the same three ingredients, RF, flames (or highly
ionised air) and a (mostly) carbon substrate.
Maybe its time for the owners of bigger coils to start lighting their wood
and rubber breakouts to see what can be produced.
Derek