Replica of Rowland's Diffraction Grating
1905-1915
Perkin-Elmer Grating Infrared Spectrophotometer
Ultraviolet grating spectrophotometer
Thorpe diffraction grating 14950 lines per inch
Circular diffraction gratings
Diffraction Grating on Glass
Diffraction Grating
1910-1915
Circular diffraction grating
diffraction ruling on metal
Hartridge prism
1984
Perkin-Elmer 257 IR grating spectrometer
circa 1980
Two Diffraction Gratings
Diffraction grating with focal power
1973-1983
Pair of glass crossed diffraction gratings in single mount
1900-1956
SP 200G grating infrared spectrophotometer
Diffraction grating
1963
Perkin-Elmer 257 IR grating spectrometer.
circa 1980
Thorp Replica Diffraction Gratings
Thorpe's Transparent Relica of Rowland's Diffraction grating
Accessories for Ebert Grating Spectrograph
1967-1968
Diffraction grating 1800 gr/mm on 6 inch diameter blank
Thorpe's transparent replica of Rowland metal diffraction grating
selection of 8 sets of diffraction rulings on polished steel
1820-1829
Control system for Ebert grating spectrograph
1967-1968
Arc control unit for Ebert grating spectrograph
1967-1968
Diffraction grating
Metal containers and mirror for Ebert Grating Spectrograph
1967-1968
Diffraction ruling on glass sheet
Ebert grating spectrograph E543 by Hilger & Watts Ltd.
1967-1968