Text: Also called Marconi Coherer‹A detector of electric waves consisting of fine nickel and silver filings contained in a suitable glass tube between two electrodes consisting of two silver plugs. These two plugs are connected to platinum wires brought out through the sealed ends of the tube, which is carefully exhausted of its air. The metallic fiiings in a loose condition have feeble conductivity for the current from a single dry cell. If a very weak electric oscillation is passed through the coherer, the filings cling together or cohere and hence conduct electricity better and they will then pass sufficient current from a single dry cell to operate a telegraphic relay. To bring these filings back to a non-conduetive condition, the tube is tapped by an electromagnetic tapper, similar - to an electric bell with the gong removed. The Marconi coherer is now obsolete. ( See Coherer. )

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