pH Meter

pH Meter

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Usage conditions apply
A pH meter measures the acidity of aqueous solutions. When asked about an instrument suitable for testing citrus fruit, Arnold Beckman, a young chemist at the California Institute of Technology, designed one with glass electrodes, and showed a prototype at the American Chemical Society meeting in 1935. He established the National Technical Laboratories in Pasadena in 1935, to manufacture this instrument. The firm became Arnold O. Beckman, Inc. in the 1940s, and Beckman Instruments, Inc. in the 1950s.
An oval tag inside the lid of this example reads “BECKMAN” and “MODEL G SER 9567 GLASS ELECTRODE pH METER NATIONAL TECHNICAL LABORATORIES SOUTH PASADENA, CALIFORNIA, U.S.A.” The Model G was introduced in 1937, and still in production twenty years later.
Currently not on view
Object Name
pH Meter
Date made
ca. 1958
National Technical Laboratories
place made
United States: California, Pasadena
Associated Place
United States: New Jersey
overall: 28 cm x 28.6 cm x 22.2 cm; 11 in x 11 1/4 in x 8 3/4 in
overall: 10 7/8 in x 11 1/8 in x 8 1/4 in; 27.6225 cm x 28.2575 cm x 20.955 cm
ID Number
catalog number
accession number
Credit Line
Gift of Beckman Instruments
See more items in
Medicine and Science: Chemistry
Data Source
National Museum of American History
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