Phosphorescent Bulbs II
Half painted black to better see phenomena
A very bright phosphorescence of glass. Note the bluish
phosphorescence of the hard glass stem compared to the green
phosphorescence of the softer soda glass bulb.
Heavy electrification of bulb. Filament occasionally lights, but
requires precise placement in the bulb for efficiency. (See Tesla
Slight reddening of filament. See ends of broken filament forming
"star burst" patterns inside the bulb.
This is quite striking in appearance!
Even on the non-painted bulb you can see heavy
See also bits of projected filament hitting the glass walls (to the
Incadescent spots appear where filaments hit the glass walls. This
eventually leads to punctures of the bulb.
The bulb to the right has a higher vacuum, backing up a spark nearly the
height of the bulb.
Here the only remaining filaments are at the wires leading out of the
Vacuum begins to change, likely due to a pin hole puncture. This
may or may not repair itself, it depends on how pliable the glass was at
the point of contact!
During one stage the vacuum was lower and then immediately became
higher, showing a "self-repair" of the bulb. This was
outlined in Tesla's 1897 lecture published
by the great Leland Andersen.
FOR A MOVIE!
(C) Jeff Behary, 2010