Roentgen X-Ray Tube


This is one of the first x-ray tubes used by physicist Wilhelm Conrad Roentgen (1845-1923), who discovered this new form of radiation at the University of Wurzburg in Germany, on November 8, 1895. While experimenting with cathode rays by passing an electric current through a glass vacuum tube covered with black paper, he noticed an unexpected green glow on a little screen covered with phosphorescent paint lying on his bench. He quickly realized that some mysterious invisible rays were leaving the tube, going through the black paper, and causing the screen to become luminous. These unknown, or "x" rays were shown to pass easily through wood, cloth, and paper, but not denser material. He showed that they could even pass through the skin and reveal the bones of the human hand. The medical diagnostic and therapeutic implications of the x-ray were realized quickly. X-ray imaging remains the most widely used form of body imaging today.

This tube was purchased from a private owner in Germany and presented to the Smithsonian Institution in 1956 by the General Electric Company's X-ray Department of Milwaukee, Wisc.

Date Made: ca 1896

Discovered X-Rays: Roentgen, W. C.Maker: Roentgen, W. C.

Location: Currently not on view

Place Made: Germany: Bavaria, W├╝rzburg

See more items in: Medicine and Science: Medicine, Health & Medicine


Exhibition Location:

Related Publication: Kendrick, Kathleen M. and Peter C. Liebhold. Smithsonian Treasures of American History

Credit Line: Gift of General Electric Company

Data Source: National Museum of American History

Id Number: MG.M-06905Catalog Number: M-06905Accession Number: 204068

Object Name: x-ray tubetube, x-rayOther Terms: Case, Tube, Roentgen; x-ray tube; Diagnostic Medicine

Physical Description: glass (overall material)wood (overall material)Measurements: overall: 6 in x 7 in x 10 in; 15.24 cm x 17.78 cm x 25.4 cmoverall, case: 5 3/4 in x 10 1/4 in x 7 3/4 in; 14.605 cm x 26.035 cm x 19.685 cm


Record Id: nmah_727539

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