From: Gary Lau 10-Dec-1997 1244[SMTP:lau-at-hdecad.ENET.dec-dot-com]
Sent: Wednesday, December 10, 1997 10:51 AM
Subject: Colored sparks
Last night I placed a small wad of paper towel, soaked in water, and
thickly covered with table salt on my torroid such that this would
constitute a breakout point. The streamer that originated from this
point was beautiful - BRIGHT sodium-yellow for about the first foot of
arc, then fading to the usual blue-violet. Try it!
I'm anxious to try salts of other metals - copper, barium, and strontium
come to mind. Two things though. As the arc vaporized the salt, it was
re-deposited on the surface of the torroid, so that even after removing
the salty wad, sparks leaving the torroid were somewhat yellow (perhaps a
concern for purists, may also be corrosive to the aluminum tape). Also,
while NaCl vapors and dust are harmless, other salts may not be.
Waltham, MA USA