The bland orange-yellow of sodium-vapor lamps now lights hundreds of miles of U. S. highway. Until recently it has been a ticklish and costly job to get the sodium into the highly evacuated lamps ...

Making plasma from metal vapor is a bit unusual, though, and the sodium experiment is pretty interesting and a fun use of that Tesla coil in your closet.

While an unfortunate few still suffer under one of the awful colors offered by vapor discharge lamps, like the pink or orange of sodium or the greenish-white of mercury, most municipalities have ...