LARGE ANTIQUE CROOKES TUBE, WORKING HEATING EFFECT, FINE BASE, GEISSLER X-RAY For Sale
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LARGE ANTIQUE CROOKES TUBE, WORKING HEATING EFFECT, FINE BASE, GEISSLER X-RAY:
$254.89
You are looking at a large working antique Crookes Heating Effect Tube together with its wooden base.
The tube is in great condition and is 17\" tall with a bulb diameter of 5”. The distinctive type of terminal end caps were first used by German manufacturer Leybolds Nachfolger from 1914 and continued to be used till the 1930s, so the tube can be dated to that period. When powered by an induction coil the concave cathode focuses electrons onto the diamond shaped platinum foil which then glows red hot due to their impact. In this example the cathode sits in a cup shaped glass shield to prevent stray electrons. The wooden base is finely turned and more ornate than most. It has some old laboratory serial numbers which can be left or could be removed.
This was one of William Crookes original designs, described in his ‘On Radiant Matter’ lecture of 1879 (see pictures). Almost all these tubes have a small hole melted in the platinum foil, but in this tube the hole is offset from the focus point. Probably someone was deflecting the electrons with a magnet at the time, but it has the advantage that a focussed red spot still appears when the tube is run, see the photos.
This is a great opportunity to own a great antique working example of this classic tube, originally demonstrated by Sir William Crookes in 1879.
Post and packing at cost depending where you are in the world, see the prices in the listing. Packaging will be done with the care that this item deserves. I can accept payment by all the usual methods and potential buyers are welcome to email with any other questions they may have.
Thanks for looking and please take time to look at my other interesting and unusual items
