Photoelectric Colorimeter
name: label: maker
content: Klett Manufacturing Company
notes: label: Description
content: Photoelectric colorimetry was a hot topic in the mid-1930s when Arnoldus Goudsmit Jr. and William Henry Summerson described a photoelectric colorimeter of their own design. As graduate students at the Cornell University Medical College, Goudsmit and Summerson knew that the "progress of analytical biochemistry in the past 30 years has been closely associated with the use of the colorimeter as a measuring instrument," and they believed that an instrument that used standard photocells to measure the intensity of light would give more reliable results than one that depended on the eyesight of individual people.
label: Description
content: Summerson applied for a patent in 1938, one year after receiving a PhD in biochemistry. The Klett Manufacturing Co. of New York began marketing this instrument in 1939, noting that it would "bring the convenience, speed, accuracy and other advantages of photoelectric colorimetry to the laboratory" and provide "analytical precision in an instrument that is simple and easy to operate." The original model was still available in 1965; the same in a slightly different housing could still be had in 1974.
label: Description
content: The inscription on this example reads "KLETT-SUMMERSON / PHOTELECTRIC COLORIMETER / PAT. NO. 2193437-1940 / KLETT MFG. CO. / N.Y. U.S.A. / MODEL 900.3 / SERIAL 12 246 / VOLTS 115 / MAX. WATTS 100." The instrument was made after the issuance of Summerson's patent (#2,193,437) in 1940. The National Institutes of Health transferred it to the Smithsonian in 1980.
label: Description
content: Ref: A. Goudsmit Jr., and W. H. Summerson, "A Variable Layer Photoelectric Comparison Photometer," <i>Journal of Biological Chemistry</i> 111 (1935): 421-433.
label: Description
content: Summerson, "A Simplified Test-Tube Photoelectric Colorimeter, and the Use of the Photoelectric Colorimeter in Colorimetric Analysis," <i>Journal of Biological Chemistry</i> 130 (1939): 149-166.
label: Location
content: Currently not on view
place: label: place made
content: United States: New York
topic: label: Subject
content: Optics
label: Subject
content: Color
label: Subject
content: biochemistry
setName: label: See more items in
content: Medicine and Science: Chemistry
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content: Saccharimeters
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content: Measuring & Mapping
creditLine: label: Credit Line
content: National Institutes of Health
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1980.0644.4
label: catalog number
content: 1980.0644.4
label: accession number
content: 1980.0644
objectType: label: Object Name
content: colorimeter
label: Object Name
content: Colorimeter
physicalDescription: label: Physical Description
content: aluminum (overall material)
label: Physical Description
content: steel (overall material)
label: Physical Description
content: rubber (overall material)
label: Measurements
content: overall: 22 cm x 46 cm x 17.8 cm; 8 21/32 in x 18 1/8 in x 7 in
label: Measurements
content: overall: 8 3/4 in x 6 1/4 in x 17 1/4 in; 22.225 cm x 15.875 cm x 43.815 cm