- In a constant deviation spectrometer, the collimator and telescope are fixed in place and the observed wavelength is varied by rotating the prism or diffraction grating in the central box. The “ADAM HILGER LTD / LONDON / ENGLAND” inscription on the eyepiece of this example identifies the manufacturer. The “JAMES G. BIDDLE / PHILADELPHIA, U.S.A.” inscription on a brass plate identifies the firm that brought the instrument into the United States.
- Adam Hilger, Ltd. introduced its first constant deviation spectrometer in 1904, noting that the prism was designed by Messrs. Pellin & Broca, and described in the Journal de Physique in 1899. The form proved remarkably successful, and remained on the market for decades. This type of Modified Wavelength Spectrometer was made between 1914 and 1926; this example was made in 1920, and used at the National Bureau of Standards. The arm between the collimator and the prism can hold one of three high-resolution multiple-beam interferometers: a Michelson echelon diffraction grating, a Lummer-Gehrcke parallel plate, or a Fabry-Perot etalon.
- Ref: Arthur H. Thomas Company, Laboratory Apparatus and Reagents (Philadelphia, 1914), p. 495.
- Noah Rindos, “A Constant Deviation Wavelength Spectrometer Made by Adam Hilger, Ltd.,” Rittenhouse 12 (1998): 25-29.
- Charlotte Bigg, “Adam Hilger, Ltd and the Development of Spectrochemical Analysis,” in Peter J. T. Morris, ed., From Classical to Modern Chemistry. The Instrumental Revolution (London, 2002), pp. 111-129.
- Currently not on view
- Object Name
- spectrometer, constant deviation
- date made
- place made
- United Kingdom: England, London
- overall: metal accesories: 3 5/16 in x 13 7/8 in x 3 1/2 in; 8.4455 cm x 35.2425 cm x 8.89 cm
- overall: 12 1/2 in x 20 in x 19 1/2 in; 31.75 cm x 50.8 cm x 49.53 cm
- ID Number
- catalog number
- accession number
- Science & Scientific Instruments
- See more items in
- Medicine and Science: Physical Sciences
- Data Source
- National Museum of American History
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