There is, however, another possible way how a conductor might at least appear to phosphoresce.
Its dead color brightens considerably under the molecular impact, but I am now convinced it does not phosphoresce.
Some substances also, which fluoresce at ordinary temperatures, will phosphoresce at low temperatures.
But from numerous experiments I find that bodies will phosphoresce in actual contact with the negative pole.
I took a screen made of zincblende, which will phosphoresce when the emanations of radium fall upon it.