Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2023 May;33(2):230-242.
doi: 10.1016/j.zemedi.2022.12.002. Epub 2023 Apr 19.

Claims of priority - The scientific path to the discovery of X-rays

Uwe Busch  1
Affiliations
Review

Claims of priority - The scientific path to the discovery of X-rays

Uwe Busch. Z Med Phys. 2023 May.

Abstract

Shortly after Röntgen's publication about a new kind of rays, a dispute about priority claims began. Röntgen was not the first researcher to produce X-rays nor the first to take X-ray images. An analysis of the history of cathode ray research in the 19th century reveals ample evidence that researchers before Röntgen had already produced X-rays, albeit without knowing this. Most of them, for their part, did not claim any priority, some did so rather casually. The German-Hungarian physicist Philipp Lenard, a co-founder of German Physics, considered himself a "true discoverer". It remains to be said, however, that he, like many others before him, failed to recognize the character of the new radiation. It was Wilhelm Conrad Röntgen, with his three scientific publications on X-rays, who laid the foundations for their physical clarification and paved the way for the success story of their application in a variety of fields that continues to this day.

Keywords: 100th anniversary of his death; Canal rays; Cathode rays; Crookes tube; Electron; First X-ray image; Gas discharge; Heinrich Geissler; Hittorf tube; Lenard window; Priority claims; Puluj lamp; Radiating matter; Unipolar vacuum tube; Wilhelm Conrad Röntgen; X-rays.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Michael Faraday by Thomas Phillips oil on canvas, 1841–1842 35 3/4 in. x 28 in. (908 mm x 711 mm) Purchased, 1868 NPG 269. (Michael Faraday – Wikipedia Wikimedia Commons).
Figure 2
Figure 2
Schematic diagram and photograph of a direct current glow discharge showing the following structures: The cathode glow, i.e., the first violet glowing region immediately adjacent to the cathode; the cathode dark space (Hittorfscher Dunkelraum), i.e., the darker band between the two brighter regions adjacent to the cathode, where the electrons already have energy above the maximum of the excitation energy and can no longer excite the gas as efficiently; the negative glow, i.e., the second larger purplish glowing region next to the cathode, whose brightness gradually decreases toward the anode; the Faraday dark space, i.e., the region without glow near the center of the tube; the positive column, i.e., the pink glowing region filling the right side of the tube and representing a plasma with hot electrons. This region is characterized by low electric field strength and vanishing space charge and ensures current transfer between cathode and anode. In the photo, striation, i.e. alternating bright and dark bands, can be seen in the positive column, caused by an instability in the plasma; the anode glow, i.e. the bright layer on the far right in front of the anode (Gas discharge - Category:Gas discharge tube - Wikimedia Commons).
Figure 3
Figure 3
Plate VII ’A continuation of the Experiments on the Attrition of Glass’ and ’Some further Experiments relating to the Electricity of Glass’ from Physico-Mechanical Experiments on various subjects, presented to the Royal Society on October 26, 1709 (Francis Hauksbee – Wikipedia Wikimedia Commons
Figure 4
Figure 4
Julius Plücker (1801–1868). Lithographie von Rudolf Hoffmann, 1856. (Julius Plücker – Wikipedia Wikimedia Commons).
Figure 5
Figure 5
Heinrich Geissler (1814–1879). (Heinrich Geißler (Glasbläser) – Wikipedia Wikimedia Commons).
Figure 6
Figure 6
Johann Wilhelm Hittorf. Taken from the Festschrift on the occasion of Johann Wilhelm Hittorf’s 80th birthday. Leipzig: Barth 1904. Adolf Heydweiller, Münster (Johann Wilhelm Hittorf – Wikipedia Wikimedia Commons).
Figure 7
Figure 7
Gas discharge tube of the Hittorf type. The first experiments with X-rays took place with tubes that were initially still cylindrical. The end of the glass bulb acted as an anti-cathode, but the radiation was still quite diffuse. (Archiv Deutsches Röntgen-Museum).
Figure 8
Figure 8
Crookes shadow cross tube (Crookes tube two views - File:Crookes tube two views.jpg - Wikimedia Commons).
Figure 9
Figure 9
Canal rays: Anode-ray tube showing the rays passing through the perforated cathode and causing the pink glow above it (Anode ray - Wikipedia Wikimedia Commons).
Figure 10
Figure 10
Puluj lamp. Courtesy of Museum Experimentalphysik Innsbruck.
Figure 11
Figure 11
X-ray image of two American coins. (Archiv Deutsches Röntgen-Museum).
Figure 12
Figure 12
Telegram from Tesla to Röntgen dated March 14, 1896 (Archive Deutsches Röntgen-Museum).
Figure 13
Figure 13
Lenard discharge tube (Archive Deutsches Röntgen-Museum).
Figure 14
Figure 14
Wilhelm Hallwachs (1859–1922) (Wikimedia commons. Wilhelm Hallwachs | Niels Bohr Library & Archives (aip.org)).
Figure 15
Figure 15
Advertisement for X-ray tubes by the Gundelach company from May 1896 (Courtesy of Glasmuseum Gehlberg).
Figure 16
Figure 16
Röntgen’s glass plate for investigating permeability with increasing layer thickness (Archiv Deutsches Röntgen-Museum).
Figure 17
Figure 17
Joseph J Thomson (1856–1940) steel engraving from 1896. Taken from The Electrician, 1896 - The Electrician, 1896, p.120 ISBN 0-87942-238-6, (File:JJ Thomson.jpg - Wikimedia Commons) Wikimedia Commons.
Figure 18
Figure 18
Wilhelm Conrad Röntgen in his physics institute in Würzburg portraits by Nicola Perscheid (1864–1930) for the making of the Röntgen Monument by Reinhold Felderhoff (1865–1919), which was erected on the Potsdamer Bridge in Berlin in 1898. (Archiv Deutsches Röntgen-Museum).
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

  • Röntgen's last will.
    Treutwein M. Treutwein M. Phys Imaging Radiat Oncol. 2023 Nov 8;28:100503. doi: 10.1016/j.phro.2023.100503. eCollection 2023 Oct. Phys Imaging Radiat Oncol. 2023. PMID: 38035208 Free PMC article. No abstract available.

References

    1. Parts of the article are taken from the book: Busch U (Ed.). Wilhelm Conrad Röntgen – A shining life for science. Classic texts in science. Birkhäuser; 2021. p. 94–6.
    1. More H. Cathode rays; 2020. https://thefactfactor.com/tag/faradays-dark-space/. Site visited 20.10.2022.
    1. Hauksbee F. Physico-mechanical experiments on various subjects, containing an account of several surprizing phaenomena touching light and electricity. Producible on the attrition of bodies. With many other remarkable appearances, not before observ'd. Together with the explanations of all the machines, (the figures of which are curiously engrav'd on copper) and other apparatus us'd in making the experiments. London, Printed by R. Brugis, for the author; 1709. p. 133–97. https://archive.org/search.php?query=Hauksbee%20Physico-Mechanical
    1. Hittorf J.W., Plücker J. On the spectra of ignited gases and vapours with especial regard to the same elementary gaseous substance. Philos Trans R Soc (Lond) 1865;155:1.
    1. Hittorf J.W. Ueber die Elektricitätsleitung der Gase. Ann Phys Chem. 1869;212:1–31. 197–234.

LinkOut - more resources