The Cathode Ray Tube site
History and Physics Instruments
Wilhelm Conrad Röntgen
The first X- ray picture.
It's the hand of Röntgen's wife Anna Bertha, she lived from 1839-1919. The picture was taken on 22 December 1895. Click at the hand to visit the Deutsches museum for more Röntgen info.
Wilhelm Röntgen (1845-1923)
Röntgen was born in Lennep Germany and moved with his parents to The Netherlands in 1848 where he went to the technical school in Utrecht which he didn't complete. Due to this he was refused on the University of Utrecht. He managed in 1865 to study on the Swiss University in Zurich. After several studies at different Universities in Germany he worked as a Professor on the University of Würtzburg where he did the discovery of X-rays.
During his research on cathode rays which started in 1895, he noticed that a plate of barium platino-cyanide crystals on a table six feet away in his workroom glowed when he activated the tube. Even after covering the tube with black cardboard it kept glowing. Röntgen linked this to the working of the tube and named this strange phenomena X-rays. In next experiments he used a photographic plate and made his first X-ray pictures, one of them the hand of his wife Anna Bertha.
Which tube Röntgen used during his discovery is not clear, it is known that he had several which he had ordered to his own description for research. He also used different tube suppliers as a source for his tubes (Louis Müller-Unkel, Greiner & Friedrichs, Emil Gundelach), resulting that more than one claimed that they had made the tube used during the discovery. It resulted in a boost of newly developed tubes for the discovered rays.
Röntgen who gave the name to this rays never patented the invention. He was rewarded with the Nobel prize for Physics in 1901.
From as early 1879 many scientists were interested in the newly discovered Radiant Matter (cathode rays) by Sir William Crookes. Several reports are known of witnessing strange spots on photographic plates in their work rooms after experimenting, although no one spent much attention on it. (due to X-rays normally produced by Crookes tubes)
Six weeks after his discovery he published his results on December 28th in "On a New Kind of Rays". After the publication scientists all over the world repeated his experiment using their Crookes tubes. A.A. Campbell Swinton (like many others) did the same experiments in England with a newly developed X-Ray tube made by A.C. Cossor (a famous producer of high quality Crookes tubes) after a description by Röntgen.
It was a small pear shaped tube with two electrodes one in the form of a ring which can be seen against the wall on a photographic picture from The Windsor Magazine 1896 spring section.
The first X-ray photographs in the US were made using a Puluj lamp by Edwin and Gilman Frost on February 3, 1896.
In Germany a museum is dedicated to Wilhelm Röntgen and his work.
The paper which Röntgen published in 1895 On a New kind of Rays can be found at the site of mindfully.org.
A biography of Röntgen can be found here.
The platinum foil inside the tube.
The foil is a little deformed due to the heat generated by the stream of electrons.
It actually burned a hole in the foil.
The concave cathode
To converge the electron beam to focus on the small platinum anode.
Jackson X-ray tube
This early X-ray tube from the late 19th century was
developed by Professor Herbert Jackson (1863-1936) in
1895, he worked at King's College in London and did
research on fluorescence and luminescence in vacuum
tubes. Jackson developed the typical concave cathode
as can be seen in the upper part of the tube.
During his research he accidentally discovered the X-
ray phenomena prior to Röntgen, though he was not
aware of their significance.
A small piece of information is public at JSTOR.
Jackson focus tube ca 1896
Demonstration of an early X-ray photography 1896.
From the article; The New Photography By Cathode Rays, Scribners' magazine April 1896 by John Trowbridge.
A.A.Campbell Swinton demonstrating an early X-ray
tube for the Royal Photographic Society 11 Febr 1896.
This picture is from The Windsor Magazine 1896
On the white paper in the back left the first pear shaped X-ray tube to the right a model after Hittorf. (picture courtesy Alastair Wright)
There is a tube of this model at the Science museum in London.
Large Early X-ray tube
This early odd English tube has a length of about 50 cm with a simple tiny rod cathode and a heavy metal anode.
The blue glass seals and platinum connections indicate a production date of late 1800, so it is possibly an experimental tube from the time that the X-rays were invented. It was used in a school as an X-ray tube.
This tube was kindly donated by Ian Poole.
The heavy anode 15x15x15mm made to withstand the heat generated by the use has an unusually shape.
Looking at the deposit on the glass it could never have a sharply focussed ray.
The picture on the right Professor Röntgen at work
"in the midst of an experiment on the new light"
with an elongated tube.
The drawing is made by Walter E. Hodgson
in 1896 for The Windsor Magazine.
The old label tells the phosphorescent composition on the mica screen.
ca 1885 or earlier
First medical X-ray in the US
Drs Edwin and Gilman Frost using a Puluj lamp for their first X-rays on 3 February 1896, notice the bright light generated by the tube.
Here a link to the original PDF article from the Dartmouth Medical school.
And here another one describing the same historical fact (arjonline.org).
Actual setup with the Puluj lamp of Frost.
Large Puluj lamp
Height 34cm ~1900
Early simple model X-ray tube
This is a rare two electrode type X-Ray tube
from around 1900 designed by Crookes.
Click on the picture to see a larger version of this sheet with the first publication of early X-Ray tube models.
(La Nature 1896)
The tubes were owned by Gaston Séguy and show designs of several scientist.
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X-ray tube with duplex regulator ca 1900
On the tube is etched; G.M. no.298815 witch is a type numbering of C.H.F Müller. This tube has a bulb diameter of 10cm and has a duplex regulator with mica plates, which was an "automatic"regulator. When the tube gets "hard" a flash-over from the wire will result in a flashover in the mica which release a little bit of air. This kind of tube was suitable for fluoroscopy and photography and produced in different sizes.
Early Villard X-ray tube.
From around 1900 with an osmosis palladium regulator (the small metal tube on the right). When this palladium tube was heated, hydrogen diffused through this small metal tube and regulated the vacuum in the X-ray tube.
Radiguet Muret Bi-Anode focus Ion X-Ray tube ca.1898-1899
This is a rare example of the first tubes made by Radiguet & Massiot Paris.
The Muret tube was built for "fluoroscopy and thick bodies". The tube still contains its vacuum and has a nice purple patina inside, a sign of good use.
Bulb diameter 15cm.
Radiguet & Massiot
Massiot joined the Radiguet company in
1899. This type Muret focus X-ray tube
has both signs, the single Radiguet label
outside and Radiguet & Massiot
stamped inside on the cathode. So it is
likely to believe that this tube was
produced around 1899. The Paris St
Antoine hospital in Paris bought two of
these tubes in 1899 for 30 Francs for
their first "chamber of radioscopy".
Look here for their inventory.
Radiguet neo-occultism, X-ray entertainment in 1897.
The picture comes from the French 1897 book "Traité de
Radiographie" showing a neo occultism X-ray trick which was practiced by Radiguet, scaring people for fun. The room was littered with fluorescent props, even the clothes were fluorescent which gave a spooky presence. The fluorescence was activated by an X-ray tube in the room.
At that time no one was aware of the harmful radiation. Read here the article from the Lewiston evening Journal from April 2 1897.
Muret tube picture from the book Manuel de Radioscopie et de Radiographie third print 1900.
The potash regulator
The potash regulator (first used by Crookes) is the predecessor of the palladium regulator introduced by Villard.
The regulator tube was needed to restore the
correct vacuum which constantly changed in
these early tubes when used. After heating the glass regulator stem with a flame, a small amount of gas was released into the tube.
X-ray tube production in England
Cuthbert Andrews (1882-1972) was a leading English
manufacturer of X-ray tubes in the early days.
C.H.F Müller a large German X-ray tube maker, wanted to
produce and sell X-ray tubes in Britain. In 1909 Andrews
came in contact with Mr. Müller and by 1912 Andrews
started producing X-ray tubes for the English market.
Andrews his company was virtual the only manufacturer of
conventional X-ray tubes in Britain after 1930.
His company produced over more than 30.000 tubes of 75
different shapes. This text is extracted from an article
which can be found on site of RHHCT.
Puluj phosphorescent lamp
Johan Puluj was a Ukraine Scientist who
studied in Vienna and developed this tube in
1881 to demonstrate a new light source. The
early catalogues tell man could read easily in
its light, not aware of the harmful X-rays which
The small oval mica screen is covered with
calcium wolframite CaWO4 also called
scheelite or calcium tungstate and lights up
white blue when hit by electrons.
These lamps were sold with different
phosphorescent materials for different colors
Due to the fact that the mica plate was built
at an angle of 45 degrees the amount of X-
rays was high enough to make X-ray
The first US medical X-ray photographs were
made with this lamp in 1896.
Here you can find a link to a PDF with some
interesting info about Puluj and the X-ray
discovery from the international conference
of the European Society for the History of
Alan Archibald Campbell-Swinton (1863-1930)
He was one the first to explore medical applications
and opened the first radiographic laboratory in
England in 1896.
In 1908 he published the article "Distant Vision" in
Nature describing the use of cathode ray tubes for
The use of the third electrode
was an arbitrary thing.
From the beginning it was
common with the German tubes
(as it would lower the
resistance) but more
uncommon in France and
England. C.H.F. Müller
produced two electrode tubes
specially for France where the
three anode tubes were called
Another Puluj lamp
Height 30cm ~1900
Notice the different build of this tube, even the lower round plate (cathode) has a separate glass support.
Ion tube mounted on an X-ray stand.