This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Millikan's Oil Drop apparatus c. used by Robert Millikan and Harvey Fletcher in several experiments to measure an electron's charge Museum of Science and Industry Chicago DSC. en Exhibit in the Museum of Science and Industry Chicago Illinois USA Photography was permitted in the museum without restriction own Daderot cczero