Comparator Made by Warner and Swasey for use by S.P. Langley
Comparator Made by Warner and Swasey for use by S.P. Langley
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- Description
- Smithsonian Institution staff have long used instruments, made in both the United States and abroad, to record and to analyze scientific data. For example, in 1887 astrophysicist Samuel Pierpont Langley (1834 -1906) began working as assistant Secretary at the Smithsonian, while retaining his position as head of the Alleghany Observatory in Pittsburgh. He was promoted to the position of Secretary of the Smithsonian that same year, and a Smithsonian Astrophysical Observatory soon was under construction in Washington. Langley had invented a sensitive instrument called to bolometer to measure the intensity of solar radiation at various wavelengths. It produced records on glass plates 60 cm. long and 20 cm. wide. To measure these, Langley and his associates used this apparatus, called a comparator, and a microscope that moved along the carriage of the comparator (this microscope is not present in the museum object). This particular comparator was made for the Smithsonian by the firm of Warner & Swasey Co. of Cleveland, Ohio.
- References:
- S. Pierpont Langley, Annals of the Astrophysical Observatory of the Smithsonian Institution, vol. 1, 1900, pp. 64-65.
- Donald L. Obendorf, Samuel P. Langley, Solar Scientist, 1867-1891, PhD. Dissertation, Berkeley: University of California, 1969
- Location
- Currently not on view
- Object Name
- Comparator
- date made
- ca 1900
- maker
- Warner & Swasey Company
- place made
- United States: Ohio, Cleveland
- Physical Description
- metal (overall material)
- Measurements
- overall: 17 1/2 in x 36 in x 12 in; 44.45 cm x 91.44 cm x 30.48 cm
- ID Number
- MA.314884
- accession number
- 211531
- catalog number
- 314884
- Credit Line
- Transfer from Smithsonian Institution Astrophysical Observatory
- subject
- Mathematics
- Astronomy
- See more items in
- Medicine and Science: Mathematics
- Data Source
- National Museum of American History
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