Riess spiral

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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. [1] They are named for German physicists Peter Theophil Riess and K. W. Knochenhauer.

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References

  1. Jed Buchwald, The Creation of Scientific Effects: Heinrich Hertz and Electric Waves, 1994: Ch. 14: "A Novel Device", p. 219.