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Re: Conducting through glass



When I was in high school chemistry class and the instructor
was lecturing about electrical conduction by ion transfer to
the class one day he asked if anyone knew of a good example
of this kind of conduction; when I said molten glass would
conduct you should have heard that moans and laughter
in the room.

Which all stopped when the instructor got a length of labratory
soda glass from the back room and turned it orange and taffy
soft over a set of metal prongs connected to a 110 volt standard
60 watt lightbulb...  and the bulb popped on at full brightness.

>
>You have read the comments to your post. I would now like to
>add that glass can indeed conduct electricity. If you place a
>piece of glass (tubing or thin solid rod works best) between the
>electrodes of a HV xformer and heat the glass to a bright red-
>orange (with an external flame or the HV discharge itself), it will
>start to conduct and glow on its own. In (semi)fluid state, glass
>will allow ions to migrate from one end to the other resulting in
>a high (kohms) ohm resistor. This gets very hot from the I^2*R
>losses. However, it is kind of interesting to see a light bulb
>"filament" made out of glass. You can do something similar in a
>µwave oven (off topic). However be careful, if you try this or the
>above. Don´t use a hand held propane torch to heat the glass
>(because of the obvious shock hazards). It won´t work with the
>output from a TC, because the current isn´t high enough.
>
>Coiler greets from Germany,
>Reinhard