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Quartz/Halogen incandescent bulbs



I don't think that the body oil on the surface acts to 'breech the
degeneracy' of the vitreous quartz.

It doesn't. It catalyzes a relaxation from the vitreous state to
the lower free energy crystalline state. I was responsible for the
devitrification of a mercury arc envelope when I was a graduate
student. They cost $75 each in 1960, so the lesson was memorable.
(No, I didn't have to pay for it.) The devitrified quartz, I was
told, opens a very small air leak into the envelope. The arc
gradually goes bad. Unlike a quartz halogen bulb the pressure in a
mercury arc lamp is below one atmosphere, so there is no tendency
to blow a bubble. I haven't seen the phenomenon mentioned, but I
wasn't referring to a quartz halogen envelope anyway. I have seen
some dandy bubbles blown by glass (not fused quartz) 35mm and
overhead projector bulbs, however.

Leigh

Gratuitous English grammar lesson follows:

"Break the degeneracy!" "Breech" is a noun; "break" is the verb. I
am sensitive to the difference because I was raised by folks who
thought the difference mattered. I realize that my attitude is not
politically correct. I still think "lend" is a verb and "loan" is
a noun, and that's the way it was when I went to kindergarten
sometime during the late Pleistocene. There seems to be a move
afoot to make the English language more degenerate by reducing the
number of distinct parts of speech! Isn't it interesting that the
term "degenerate" can be interpreted in two ways here? I always
wondered about how that word got attached to two or more equal
energy states. One who uses "loan" as both a verb and a noun is
practicing degenerate grammar.