Concave Rowland diffraction grating on speculum metal
1894
Concave Rowland diffraction grating on speculum metal
1898
Plane Rowland diffraction grating on speculum metal
1895-1909 (estimated)
Langley's 'Great' Bolometer, 1880-1890
1880-1890
Langley's Bolometer, 1880-1890
1880-1890
Concave Rowland diffraction grating on speculum metal
1899
Concave Rowland diffraction grating on speculum metal
1894
Concave Rowland-type diffraction grating on speculum metal
1882-1909 (estimated)
Concave Rowland diffraction grating on speculum metal
1882, Nov 6