: what if someone were to drill a hole in a round glass sheet in the center. : placing the glass on a ceramic flowerpot centerd upon the edges of a glass plate, with bolt in the center and everything secure the glass is heat gradualy with a torch untill it begins to reden slightly, then the bolt is carfully pulled downward into pot slightly, in order to slowly bend the glass into a paraboloid. : does anyone have any comments?

This in itself will not work because the deforming force must be uniform across the glass. I doubt that it could becontrolled but you might try with out the bolt and let gravity do its thing.

A 36" IR flux scope was made this way by just applying a vacuum. Of course due to uneven strain, it was useless visually. Still pretty neat to map the galaxy in IR.

Experiment I say! -Rick