
Filings coherer, glass tube with side pocket mounted on cylindrical rod with brass screw terminals at ends, 1894-1904
1894-1904
1894-1904
1894
1894-1904
1894-1904
1895-1900
1894-1904
1894-1904
1900-1910
1899
1894-1904
1894-1904
1890-1894
1894-1904
1900-1910
1894-1904
1894-1904
1894-1904
1900-1910
1898
1894-1904
1900-1910
1890-1896
1899-1901
1900-1910
1894-1904
1899
1898
1894-1904
1894-1904
1898
1894-1904
1900-1910
1894
1900-1910
1894-1904
1902
1894
1895-1906
1894
1889
1885-1940
1902
1894-1904
1885-1940