A friend of mine told me about how boats long ago used incandescent bulbs that were re-usable. The bulbs all had a way of opening them up and replacing the filament. And the boats carried a light bulb repair kit, complete with a bunch of filaments. Imagine: a light bulb that lasts forever. You just have to mend it with a bit of filament every couple of years. Maybe filaments come in 100 packs for $5.
Anybody know of anything like that existing today? Anybody know of a web page that talks about the old stuff?
joan from zone 6 wrote: i wonder how they pulled the vacuum needed ?
I think incandescent bulbs are filled with inert gas. maybe there's a vacuum, too. some high intensity discharge lamps involve vacuums. maybe I have no idea what I'm talking about.
The earliest bulbs used a vacuum. Early in the 1900's someone discovered that using an inert gas made the lamp brighter and reduced darkening of the inside of the glass.
Because of the need for either a vacuum or insert gas or at least the absence of oxygen I have trouble understanding why a rebuildable light bulb would have ever been developed or made practical. If there really was such a thing it would be very interesting to see an example and the rebuild kit.