 Geissler Tubes
These intricate glass gas-filled tubes were made in the early 1900s, as a
scientific curiosity for use with the induction spark coils which were popular at the
time. My tubes below are all 5-6" long. Larger and more intricate tubes were made, in
sizes up to 18", with the glass tube formed into all sorts of twists, bows and spiral
shapes.
The inverter modules for cold-cathode flourescent (CCFL) LCD panel
backlights work very well for powering geissler tubes, although you shouldn't use them for
extended periods as they probably over-drive the tubes - they get warm pretty quickly!
Original 1914 advertisment
for geissler tubes here More
Geissler tubes here Large
collection of geissler and crookes tubes
Spiral tube - half the spiral is made of uranium glass, which fluoresces with a green
colour.
Wobbly tube, with centre section made of green uranium glass.
The high frequency supply causes this 'dotting' effect - the size and spacing
varies with voltage and frequency.
Intricate tube, unfortunately the sealing pip was broken so it doesn't work.
Another dead tube.(moral : always carry a high-voltage tester when buying!).
Liquid filled tube, only lights very weakly - probably leaky.
Replica tube, 10" long (details at bottom of page)
This tube has an outer sleeve containing a clear liquid, which gives a blue
hazy glow surrounding the inner spiral.
I mounted this one on a small box containing an infra-red receiver and an inverter from
an LCD panel backlight, lighting the tube whenever you fire the TV remote at it.
A couple of two-section tubes, the lower one having different gases in
each of the two sections. The sections are capacitively coupled by the co-axial globe
section in the middle
Varying the voltage and frequency produces a wide variety of different
patterns of coloured and dark zones.
A couple of other gasfilled discharge tubes, with capillary sections which glow
very brightly.

Tube with four liquid-filled sections, at
the Powerhouse Museum Sydney.
Below are some amazing geissler tubes from the Pressler
Collection, pictures courtesy of David Stanley
Auctioneers. Sizes (left to right): 19", 18", 36" and 15" high.
  
Sources
Replica tubes available from this German
supplier (Babelfish
translation)
Just Neon replica geissler
tubes.
Several people have asked me where to find Geissler tubes - I got most of mine from an
auction of scientific antiques at Christies, so you should check out the larger auction
houses for sales of scientific antiques, and also scientific antiques dealers.
There are a couple of London based scientific antiques dealers who have shops open on
Saturday mornings in the Lipka Gallery, off Westbourne Grove at Portobello road market,
both of whom I've seen offering Geissler tubes at specialist antique fairs :
Scientific & Antique Ltd. Nick Webster
Tel. 20 8742 9002, Office 22-24 Ariel Way, White City, London W12 7SH
Scientific & Medical Antiques : Desmond & Elizabeth Squire 020 8946 1470, Fax
020 8944 7961, PO Box 4252, London SW20 0XS
http://www.earlytech.com/ - on-line antiques
sales and auctions, with sections for scientific/electrical items.
Edmund Scientific (New Jersey USA (609) 573-6250), and probably other educational
scientific suppliers, sell straight capillary discharge tubes like those at the bottom of
the page with a variety of different gas fillings.
I also found a source of replica Geissler Tubes, as well as other replica discharge
tubes and early valve replicas, pictured below. I saw these at the National Vintage Communications
Fair in Birmingham UK (10 May 1998). The geissler tube replica was £50, other prices
below are from memory.
The replica Geissler tube I bought (pictured above) is about 10" long, with 6mm
tubing - a bit larger & thicker than you tend to see in original tubes. The replica
has excellent detail, down to the electrode and seal appearance, although the end-caps
look like standard valve anode caps rather than the more normal cap and loop terminals.
.
 Replica R valve and another early valve .either £40 or
£90 - I couldn't read the label & forgot to ask! These look really nice - the. photos
don't do them justice!

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