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Summary
DescriptionMercury Arc Rectifier.jpg
Mercury Arc Rectifier, London, Belsize Park deep level shelter. Taken by C Ford.
English: In-service device, as you can see the blue light phenomena in the center bottom (the liquid mercury cathode spot)
Deutsch: In Betrieb befindlicher Quecksilberdampfgleichrichter. In der Bildmitte unten sind blaue Leuchterscheinungen, der sogenannten Kathodenfleck, erkennbar.
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