Cold Cathode X-ray Tube (early to mid 1900s)
Not much that is worthwhile can be said about this bi-anode x-ray tube, so you might want to stop reading and consider checking out another tube.
The cathode, as always, is positioned on the periphery of the spherical portion of the tube (in the photo, it is on the lower left side of the bulb, but it is not easily recognizable ). The anode, a simple aluminum rod, is on the long axis of the tube inside the glass arm attached to the upper right side of the bulb (as seen in the photo). The anticathode enters the tube at a 45 degree angle (from the lower right in the photo) with the circular target located in the middle of the bulb.
Obviously, the tube lacks a regulator to control the gas pressure - a serious disadvantage if the intent was to use the tube for extended periods.
As is true for most tubes of this design, the manufacturer is unknown. There are no markings of any type on the tube's glass or metal components. However, from its general appearance, I would guess that it was produced between 1925 and 1950 or so, and that it was intended for classroom demonstrations.
The lack of corrosion on the contacts, the absence of damage to the target and the lack of any coloring of the glass indicates that it saw little to no use.
Copyright 1999, Oak Ridge Associated Universities