Mxslick: Yeah, I know panels were made like this many years ago. Our Baptist church here (1926 vintage sanctuary) had two such panels - one very large one in the basement with numerous knife switches and fuseholders mounted on soapstone, marble(?), or some such non-conductive base, and a smaller panel near the sanctuary for controlling the lights (while singing "Nearer my God to Thee" for good measure). The construction work was as meticulous as it was deadly.
Concerning the theater fire, this happened about 30 years ago. I am also at a loss to understand why this would happen at a time of day when the load should have been less - no marquee lights, projector motors, sound equipment, auditorium and lobby lights, etc.
On many occasions when I would come in to open up, I would find numerous fuses so hot that they would burn my fingers. In addition, I could actually see some of the plug fuse elements showing a dull red glow in the dark - I never could understand this. Thinking this meant a bad fuse, I replaced it - same thing. I reported this to the manager several times and nothing was ever done. Even friends in the electrical business were unable to explain this situation. Everyone did agree that this was a potentially life-threatening condition.
Sorry to be getting off-topic...
Mike (mamills)