Spirit filled spark chamber

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Original poster: "Willem Bosma" <wbosma-at-stud.tue.nl> 

SNIP
 > >Original poster: "john cooper" <tesla-at-tesla-coil-dot-com>
 > >Hi Bert:
 > >
 > >Maybe I'm not following this too well but how in the world is a flammable
 > >gas, i.e., hydrogen, used in a spark gap?  Totally contained?
SNIP
  >John
 > Easy enough... you put it in a container, just like you suggested, where
 > oxygen is excluded.  There IS a bit of a problem with hydrogen, and that
is
 > that it leaks out (the molecules are small...), so hydrogen filled devices
SNIP
 >
Hello all,
In the past I made a translucent box, a small opening on top in which a
small brass outlet tube (from ballpen filling). Box partly filled with
96%-spirit. Also inside, a multi-gap sparkbridge. Also in box, submerged, a
wirewound resistor to heat the spirit. Prior to operation of the Wien
bridge, the spirit was heated  to the point that no air escaped from the
exhoust but spirit fume, and than ignite it (sniff first!..).
During operation of the bridge, heating was not needed. Operation of
sparkbridge was much better, because the copper disks hardly oxydised any
more. The exhoust fume was ignited because I did not want free spirit fumes
around and also the length of the flame is a good indicator of the
internally generated heat. However, this set-up was used with two paralleled
ignition coils as HV source and must be adapted to higher powers. I made
this about 45 years ago.
In the snipped correspondence, no mention was made of the amounts of carbon
soot that were generated in the spark chamber. The chamber had to be cleaned
from time to time and if it was opened before it had cooled down enough, the
man who opened the little door got his face full with soot from the small
explosion. It was a trick played upon newcomers...!
Regards,  Willem Bosma