Signalling through space without wires : being a description of the work of Hertz & his successors . SZEO^ZZZZZZZTZZ Simplest Receiving Arrangement: a Telephone in Circuit with Singlepoint Coherer without Tapper-back. B a needle resting against a watch-spring A adjusted by screw

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Keywords: ., bookcentury1900, bookdecade1900, bookidsi, booksubjectelectricity