Filings coherer, Lodge pattern, 1895-1900
1895-1900
Filings coherer, glass tube with side pocket mounted on cylindrical rod with brass screw terminals at ends, 1894-1904
1894-1904
Filings coherer, Lodge-Muirhead system, 1900-1910
1900-1910
Coherer, narrow-bore glass tube, 1894-1904
1894-1904
Filings coherer, Lodge-Muirhead system, 1900-1910
1900-1910
Filings coherer, glass tube, 1898
1898
Filings coherer, Lodge-Muirhead system, 1900-1910
1900-1910
Coherer with coarse brass turnings, 1894
1894
Filings coherer, glass tube capped at ends, 1894-1904
1894-1904
Filings coherer, glass tube almost of taper shape, 1894-1904
1894-1904
Coherer, with steel needle inside part-wound with copper wire, 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
Filings coherer, glass tube with side-pocket attached to mounting bracket, 1894-1904
1894-1904
Filings coherer, Lodge-Muirhead system, 1900-1910
1900-1910
Coherer, with several needles, 1894-1904
1894-1904
Filings coherer, glass tube bent at 45-degree angle at one end to form side-pocket, 1898
1898
Filings coherer, glass tube bent into U-shape at one end, 1894-1904
1894-1904
Filings coherer, small glass tube with bulb at one end, 1894-1904
1894-1904
Coherer, coarse iron turnings, 1894-1904
1894-1904
Filings coherer, glass tube formed into bulbs at each end at right angles, 1899
1899
Filings coherer, glass tube containing powdered copper, bulb at one end, 1894-1904
1894-1904
Filings coherer, Lodge pattern with two wires inserted into bulb at one end, 1894-1904
1894-1904
Filings coherer, small glass tube with bulb at one end, 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
Coherer, with several needles in contact with crystal, 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-Muirhead system, 1900-1910
1900-1910
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
Filing coherer, glass tube, fitted on to mounting bracket with terminals, 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