Trådløs telegrafi: Heaviside lag, et lag af jordens atmosfære, der indeholder elektroner, har en mere eller mindre fri tilstand. Anonym illustration fra 1925. Privat samling.(Wireless telegraphy: Heaviside layer, a layer of the earth's atmospere containing electrons, has a more or less free state. Anonymous illustration from 1925. Private collection.)Anonymous Anonymous |
| € 133.36
Inklusive 25% moms |
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1925 · Engraving
· Billed-ID: 925467
Private Collection / Bridgeman Images |
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