Title: Ion chamber, early (B)
Date: 1932 (approximate)
Original Format: photograph: negative
Description: Small cylindrical electroscope with clock and photographic drum. Used by Millikan and Bowen in 1932. See Phys. Rev. 44:246-52 (1933). Mfg. CIT Physics Shop.
Collection: Scientific Instruments
Caltech Archives ID: ST-CR-11
