Iron borings coherer (Branly type), 1894

Iron borings coherer (Branly type), 1894

Filings coherer, glass tube, 1898

Filings coherer, Lodge-Muirhead system, 1900-1910

Filings coherer, Lodge-Muirhead system, 1900-1910

Coherer, with steel needle inside part-wound with copper wire, 1894-1904

Coherer, with several needles, 1894-1904

Filings coherer, glass tube capped at ends, 1894-1904

Filings coherer, glass tube formed into bulbs at each end at right angles, 1899

Filings coherer, glass tube bent at 45-degree angle at one end to form side-pocket, 1898

Filings coherer, small glass tube with bulb at one end, 1894-1904

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