Crookes radiometer
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The Crookes radiometer consists of an airtight glass bulb containing a partial vacuum, with a set of vanes which are mounted on a spindle inside. The vanes rotate when exposed to light, with faster ro
A Crookes radiometer
Crookes tube
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A Crookes tube is an early experimental discharge tube with partial vacuum invented by English physicist William Crookes and others around 1869–1875, in which cathode rays, streams of electrons, were
Crookes radiometer
…one pictured, and are often used in science museums to illustrate "radiation pressure" – a scientific principle that they do not in fact demonstrate. Crookes tube Marangoni effect…
Experimental Crookes tube belonging to Wilhelm Röntgen, c. 1890, at Gedächtnisstätte Würzburg (Rontgen Memorial), Würzburg, Germany
A Crookes tube: light and dark. Electrons (cathode rays) travel in straight lines from the cathode (left), as shown by the shadow cast by the metal Maltese cross on the fluorescence of the righthand glass wall of the tube. The anode is the electrode at the bottom
William Crookes and his glowing tubes gained renown, as shown by this 1902 caricature in Vanity Fair. The caption read "ubi Crookes ibi lux", which in Latin means roughly, "Where there is Crookes, there is light"
Crookes X-ray tube from around 1910