Riess spirals, or Knochenhauer spirals, are a pair of spirally wound conductors with metal balls at their ends. Placing one above the other forms an induction coil. Heinrich Hertz used them in his discovery of radio waves.Jed Buchwald, The Creation of Scientific Effects: Heinrich Hertz and Electric Waves, 1994: Ch. 14: "A Novel Device", p. 219. They are named for German physicists Peter Theophil Riess and .
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External links Riess spiral pair