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Thursday, July 26, 2007

Do you know what this is?


We have this artifact in our museum, but do not know what it is. Can you help us? There is a large bulb? behind a curved piece of glass. These are encased in a metal box.

The black cover for the bulb can be swung over top of the curved glass.
If you know, please use the comment area below to inform us.

1 comment:

Our museum said...

This has been identified as a film projector bulb and housing by someone at the Western Development Museum.
This is what D. Klatt wrote:

The bulb part is easiest to recognize. The round curved piece of glass inside the box is either a rear reflector, or it is a convergence lens if it is between the bulb and the larger opening when the box housing is closed. I can't tell from the photo if I'm looking at the back side of the bulb or the front side. On the outside of the front of the box you can see a round metal cover with a small square hole in the center. This is a light mask and, while in use, is flipped to cover the larger opening. Behind the opening you can see a convergence lens - this may be the same one seen in the open box of the first photo. Finally, there is the secondary convergence lens which flips in front of the square mask opening to assist directing the light intended to pass through the film. The size of the mask opening should be very near to the size of the film frame. By measuring this, you would be able to determine the size of the film intended to be used with this projector bulb assembly. There is no measuring reference alongside the object, so I'm unsure of the scale. My best guess would be a 35mm film format but if I'm misinterpreting the size, it could be 16mm.

By the way, while in use this thing would generate substantial amounts of heat. The mottled gray lining material probably is a hard formulation of asbestos. This usually is not considered environmentally hazardous unless someone scratches or otherwise disturbs it, or if parts of it are flaking off.