The Cathode Ray Tube site
History and Physics Instruments
The first discharge light
Snowball tube 30cm ca 1900
This tube probably contains a gas which a a persistence light when the tube was switched off. Anhydrous sulfuric acid in the tube which is responsible for the effect only worked mostly for a certain period of use. This tube doesn't show the afterglow effect anymore.
30cm powder tube ca 1900
These tubes were produced with different powders, most of them show a colored glow persistence when the tube is switched off In this tube a nice blue color which fades in minutes but it's difficult to photograph see below.
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This is a rare 22 cm Geissler tube filled with phosphores powder.
When the power is shut off the powder will glow for a short time.
The tube has two chambers with different phosphores powder like Barium or Strontium salts. Here the left and right cavity.
Very early Snowball tube
This 30cm tube with platinum wire connections is made well before 1900.
When activated in a darkened room you can see gas vapor inside. The tube contains a few drops of oily substance responsible for an afterglow, Probably anhydrous sulfuric acid. The effect is very difficult to photograph but it is great to see it in the dark, the persistence takes a couple of seconds to fade, see last picture.
Lecher or Hertz tube ~ 1900
This complete uranium glass tube 30 cm long was used for a setup with an oscillator to measure radio waves by showing standing waves or nodes. This was developed by the German physicist Ernst Lecher in 1888.
Setup with an Hertzian spark-gap oscillator.
Picture from the Ferdinand Ernecke catalogue 1904.
Holtz double valve tube
Length 57cm early 1900
If DC voltage is used, only one arm will discharge depending on the polarity.
Wilhelm Holtz, Physicist lived from 1836-1913
This model tube was introduced by Holtz in 1886
It's an early form of a modern diode or rectifier.
A Spectral tube or Plücker tube emits certain wavelengths of light (color) in the
capillary-thin tube in the middle. The color of the light depends on the type of gas or
vapor inside the tube. The different spectra of colors can be seen by use of a
spectroscope. These tubes were used for spectroscopy classroom demonstrations.
The practical use of this tubes was discovered through the research of Julius Plücker
a German Mathematician and Physicist who experimented after the mid 1800's with
similar models made for him by Heinrich Geissler.
Activated Pressler spectral CO tube.
Two early spectral tubes ~1900
The Cross vacuum scale demonstrates the phenomenon
of discharge at different pressures (vacuum) inside the tubes.
The pressures varies between 40 Torr (mm/Hg) lowest vacuum
(right tube) to 0.03 Torr the highest vacuum. (left tube) In this high
vacuum, used in many Crookes tubes, X-rays are produced,
only the glass emits here the distinctive apple green glow.
Large Cross vacuum scale
Sold by the Dutch reseller Salm, the frame measures 30 x 50 cm.
Litho of discharge effects at different pressures.
(Litho Tillieux 1925) 
The upper tube displays the stratification effect.
These are tubes after-Gaede who developed a new type of vacuum pump in 1905 on which several different types of discharge tubes could be connected in order to exhaust them.
The most famous one is the Lenard tube. Many of these open tubes were sold by the Leybold company. The old catalog can be found at the Max Planck instititute library.
The Pencil tube ca1900
Tube filled with a red substance with an unknown effect. Probably mercury iodide or sulfide, in both cases very toxic!
When activated or heated a yellow deposit can be noticed on the inside of the tube which disappears after a while.
De la Rive tube ca1910
This tube is used to be demonstrated on top of a electromagnet coil with a low DC voltage. In that case the discharge will turn around the metal rod in the middle of the tube. Depending on the polarity of the electromagnet the discharge will turn clock or anti clockwise.
Group of different spectral tubes
Cute small 15cm phosphorescent powder tube. ca 1900
Powders which were used used: (Leybolds Nachfolger 1905)
Blue-purple -- combinations of Strontium
Blue-green -- Baryum
Green-yellow -- Zincblende
Yellow-reddish -- Zincblende
Cream -- Zincblende
Red -- Combinations of Calcium
Large 35cm powdertube
The capacitive Geissler tube ca1920 length 35cm
In this tube two types of gasses are separated in two chambers N/CO2.
The tube only works on AC or Ruhmkorff coils.
The stratification tube ca1920 length 35cm
Due to the specific pressure inside the tube stratifications are formed.
The Mc Farlan Moore cold light tube.
ca1909 sold by Müller-Uri.
Daniel McFarlan Moore was a US inventor
trying to invent a new light in stead of the hot
and red Edison bulb. He created the
forerunner of modern fluorescent electric light
with tubing in lengths of several meters.
This lamp filled with CO2 worked like a Geissler
tube run on a simple inductor system.
He got his patent for these inventions
in 1895. There were several tube models to
choose for school science.
Picture from the Gundelach catalogue 1921
Here a very rare item, the "double lightbulb tube after Greinacher"
This tube is made of two regular light bulbs, in this case Osram Axial bulbs dated internally 1911. It should work like a Geissler tube when connected to DC only one bulb has a discharge, the filament is shortened and acts like an electrode and shows the production of heat on the filament on the cathode side which will starting to glow.
The complete McFarlan Moore setup. The stand is a replica of the original drawing from a 1909 Müller-Uri catalogue. Both tubes are original antiques.
Close-up of the breaker tube.