Filings coherer, Lodge pattern with two wires inserted into bulb at one end, 1894-1904
1894-1904
Filings coherer, glass tube with side pocket mounted on cylindrical rod with brass screw terminals at ends, 1894-1904
1894-1904
Filings coherer, glass tube bent into U-shape at one end, 1894-1904
1894-1904
Coherer with coarse brass turnings, 1894
1894
Filings coherer, glass tube almost of taper shape, 1894-1904
1894-1904
Filings coherer, Lodge-Muirhead system, 1900-1910
1900-1910
Filings coherer, glass tube containing powdered copper, bulb at one end, 1894-1904
1894-1904
Coherer, narrow-bore glass tube, 1894-1904
1894-1904
Filings coherer, small glass tube with bulb at one end and cap of red sealing wax at other end, 1898
1898
Filings coherer, glass tube with side-pocket attached to mounting bracket, 1894-1904
1894-1904
Filings coherer, glass tube bent into U-shape at one end with bulb to form side-pocket on mounting bracket with terminals, 1894-1904
1894-1904
Filings coherer, glass tube formed into T-shape at one end and bent round into U-shape at other end with bulb, 1899
1899
Coherer, with several needles in contact with crystal, 1894-1904
1894-1904
Filing coherer, glass tube, fitted on to mounting bracket with terminals, 1894-1904
1894-1904
Filings coherer, small glass tube with bulb at one end, 1894-1904
1894-1904
Filings coherer, glass tube curved into near U-shape at one end with coil winding at other end, 1894-1904
1894-1904
Filings coherer, Lodge pattern, 1895-1900
1895-1900
Filings coherer, Lodge-Muirhead system, 1900-1910
1900-1910
Filings coherer, Lodge-Muirhead system, 1900-1910
1900-1910
Filings coherer, glass tube, 1898
1898
Filings coherer, Lodge-Muirhead system, 1900-1910
1900-1910
Filings coherer, Lodge-Muirhead system, 1900-1910
1900-1910
Coherer, with steel needle inside part-wound with copper wire, 1894-1904
1894-1904
Coherer, with several needles, 1894-1904
1894-1904
Filings coherer, glass tube capped at ends, 1894-1904
1894-1904
Filings coherer, glass tube formed into bulbs at each end at right angles, 1899
1899
Filings coherer, glass tube bent at 45-degree angle at one end to form side-pocket, 1898
1898
Filings coherer, small glass tube with bulb at one end, 1894-1904
1894-1904
Coherer, coarse iron turnings, 1894-1904
1894-1904
Box for developers for imperial plates
1894-1904
Pill box filled with porphyrised copper, 1894-1904
1894-1904
Coherer, narrow-bore glass tube, 1894-1904
1894-1904