Coulter Counter-Model A


In 1949, Wallace H. Coulter discovered a method for detecting and counting particles suspended in a fluid medium, later named the Coulter principle. Forcing a particle-filled fluid through a small aperture in an electrical current modulated the current, allowing Coulter to count the number of particles in the fluid. Coulter patented his Coulter Counter in patent number 2,656,508, a “Means for Counting Particles Suspended in a Fluid” on October 20, 1953, with an improvement filed in 1956 that added a manometer to move a precise volume of fluid through an aperture. In 1958, Wallace and Joseph Coulter established Coulter Electronics, Inc. to pursue commercial applications of their Coulter Counter. This Coulter Counter Model A was used during the 1970s and 1980s at the Animal Care Facility at the University of California, San Francisco. The Coulter Counter has a wide range of applications in medicine and science, most importantly in determining red and white blood cell counts.

Ref: “Wallace Coulter, 85, Inventor of Medical Diagnostic Tools,” New York Times (Aug. 17, 1998), p. A13.

Date Made: ca 1973

Maker: Coulter Electronics, Inc.Inventor: Coulter, Wallace H.

See more items in: Medicine and Science: Medicine, Health & Medicine, American Enterprise

Exhibition: American Enterprise

Exhibition Location: National Museum of American History

Credit Line: Gift of University of California Medical Center, Animal Care Facility (through Joseph Spinelli, D.V.M.)

Data Source: National Museum of American History

Id Number: 1987.0248.01Catalog Number: 1987.0248.01Accession Number: 1987.0248

Object Name: blood cell counter

Physical Description: metal (overall material)glass (overall material)plastic (overall material)electronics (overall material)Measurements: overall: 50.7 cm x 41 cm x 24.5 cm; 19 15/16 in x 16 1/8 in x 9 5/8 in


Record Id: nmah_1200679

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