Geissler Tube - Definition

The Geissler tube was a glass tube for demonstrating the principles of electrical discharge, invented by the German glassblower Heinrich Geissler in 1857. They were mass produced from the 1880's.

Geissler tubes contain a combination or one of the following: rarefied (thinned) gasses such as neon, argon, or air, or conductive liquids or minerals. When an electrical current is passed through the tube different lighting effects are created.

Some tubes were very elaborate and complex in shape and would contain chambers within an outer casing. The very decorative Geissler tubes were often used as after dinner entertainment. As an educational tool they are also used to demonstrate the movement of electrons and the principles of a vacuum.

Geissler tubes have had a large impact on the development of such instruments as the x-ray tube, the Electrotachyscope, neon signs, and the light bulb, all of which use related vacuum and discharge principles.

External links

• Sparkmuseum: Crookes and Geissler Tubes (http://www.sparkmuseum.com/GLASS.HTM)
• Instruments for Natural Philosophy: Geissler Tubes (http://physics.kenyon.edu/EarlyApparatus/Static_Electricity/Geissler_Tubes/Geissler_Tubes.html)
• Mike's Electric Stuff: Geissler Tubes (http://homepage.ntlworld.com/electricstuff/geissler.html)