The Cathode Ray Tube site
150 years of CRT evolution
The Dutch collection
The first page, radiant matter- mineral tubes
Crookes mineral tube with calcite sample
Mineral tubes (Crookes nr 4)
After Crookes made his first announcement in 1879 he made a second one in 1881
about the fluorescent and phosphorescent properties of different materials in his pdf
article Discontinuous Phosphorescent Spectra in High Vacua.
Some minerals glow beautifully due to their fluorescent or phosphorescent behavior
when the tube is activated, phosphorescent means that the glow still continues for a
while if the excitation stops. Different samples of fluorescent minerals, shells, coral,
gemstones but even rubies and diamonds were used.
Another research from C.Doelter can be read in this (pdf) German article from 1911.
And the research of Goldstein on salts in this pdf .
Here is a list of some common used minerals in Crookes tubes.
bright green willemite
Johann Wilhelm Hittorf
1824 - 1914
Sir William Crookes (1832-1919)
Crookes paved the way for many discoveries. He worked as a Scientist in his own laboratory in London where he did all of his
research and developed a range of different types of high vacuum tubes.
In "On radiant matter", a lecture to the British Association for the Advancement of Science at Sheffield, Friday August 22 1879,
Crookes demonstrated 19 different tubes and discussed the fourth state of matter, plasma. Many of his tubes stood at the base of
further discoveries like the X-ray tube and the Braun tube which developed later on into our well known TV tube.
Look here for a complete publication of William Crookes his work in the New York Times newspaper.
A biography of William Crookes can be found here.
Johann Willhelm Hittorf (1824-1914)
Hittorf was a German Physicist who studied in Bonn under Julius Plücker, he was the German counterpart of William Crookes. In
his early days at the Münster Academy Hittorf had to made much of his own tools and instruments due to a lack of availability and
limited money of the Academy. In this research lab he did extensive research on gas discharges and made tubes with "absolute
vacuum" as early as 1865. He showed them to Geissler (before his publication in 1869) who replicated and sold these tubes.
Hittorf discovered even before Crookes in 1869 that cathode rays traveled in a straight line and that the intensity of the rays gained
with a lowering pressure. He also noticed the shadow on the glass wall when there was an obstruction the the path of the ray. Both
Crookes and Hittorff were important researchers and shared knowledge on this subject. [101, 56]
Warning, almost all Crookes tubes are high vacuum devices, they need high tension to work and can generate x-rays!
Shell samples light up influenced by cathode rays.
Crookes tubes with minerals and shells
made by Pressler
Crookes mineral egg tube (Crookes nr 4)
demonstrate the fluorescent behavior of stone and
shell minerals or even mineral sand. This kind of
tubes were made in different sizes.
Crookes mineral tube ca1910
This is an early tube with lime sample from the late 19th century. The mineral is Fluorescent and Phosphorescent.
The tube is filled with fluorescent and phosphorescent willemite minerals which glow very bright apple green.
Afterglow of the minerals
A similar mineral filled tube is displayed in the French 1869 Physics book from Dechanel.
Sir William Crookes
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List of Crookes tubes sold by Queen & Co 1888 after the
Notice the missing of No.3 which is a mineral tube like No.4 containing a diamond
demonstration of William Crookes in Sheffield in 1879.
which fluoresced bright green. These kind of expensive mineral tubes were only
made on special order. No.20 is the same tube as No.19. No.10 same as No.9.
The numbers in the catalogues corresponding to the figure drawings in the lecture.
5 mineral Crookes tube.
Probably Pressler ca 1920
These tubes were made in several sizes, this is the smallest sold. Height 27cm
Fluorescent and phosphorescent minerals
A rare Crookes tube with a large synthetic ruby sample. Produced by Emil Gundelach or Müller-Uri ca 1910
The development of crystal growth technology for synthetic ruby or corundum was done by the French chemist Auguste Verneuil in 1902 and was published in 1904.
made by Pressler ca 1935
Small tube filled with coral samples ca1930 height 16cm
Mineral samples light up influenced by cathode rays.
Coral and mineral samples light up influenced by cathode rays.
A very rare Crookes tube with natural Ceylon rubies attached to a white glass sphere.
These expensive gemstone tubes were made to order. ca 1900
Crookes mineral tube with Pektolite sample in white glass.
This is the largest mineral tube made by Müller Uri or Gundelach around 1900-1920. Height 30cm. There were different types of fluorescent glass to choose like: blue (lead), yellow, red (Didym),green (soda-lime), or white, and different mineral samples could be ordered.
Crookes Shell tube
This rare tube is most likely made by Cossor in London ~1900. Height 20cm. The tube is labeled "frog shell"
The activated tube reveils a very colourfull image.
Click on the picture to see it large.
The activated tube shows the bright yellow colour of the Pectotite and an orange colour which is phosphorescent and glows a while after the disconnecting the current, probably Calcite.
Click on the picture to see it large.
Ealy small model with glass stand
click on the picture to see it large
click on the pictures to see it large
Click on the picture for a large view