Re: strength of vacuum

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Harold Weiss" <hweiss-at-new.rr-dot-com> 

Hi Antonio,

I have seen this on a clear 25W bulb.  It had the appearance of little coils
in green, that moved all over the bulb.  At the same time the broken
filiment was wipping around the inside.  after shutdown the gas or glass
would glow for a few seconds.  I think it may be the same gas that glows
green in an aroura.  I have seen a green/pink plasma globe, and the bulb
looked similar.

David E Weiss

"Normal" lamps don't have high vacuum inside, but are actually filled
  with an inert gas at low pressure. If in the experiments some corona
  or similar light appears inside the bulb, there is no problem. But
  if nothing appears, and worse, the glass fluoresces with a green
  light, this is sign of X-ray generation. Some small lamps are said
to have high vacuum inside. I am not sure. Vacuum tubes certainly
  have (Humm... VTTCs may be dangerous...).

  Antonio Carlos M. de Queiroz