Robert A. Millikan (March 22, 1868 - December 19, 1953) was an American experimental physicist, and Nobel laureate in physics for his measurement of the charge on the electron and for his work on the photoelectric effect. He served as Chair of the Executive Council at Caltech from 1921 to 1945, that school's governing body at the time. He also served on the board of trustees for Science Service, now known as Society for Science & the Public, from 1921 to 1953.
"The fact that Science walks forward on two feet, namely theory and experiment, is nowhere better illustrated than in the two fields for slight contributions to which you have done me the great honour of awarding me the Nobel Prize in Physics for the year 1923.
Sometimes it is one foot which is put forward first, sometimes the other,
but continuous progress is only made by the use of both - by theorising and then testing, or by finding new relations in the process of experimenting and then bringing the theoretical foot up and pushing it on beyond, and so on in unending alternations."
- physics laureate Robert Millikan in his lecture 100 years ago
Millikan was awarded the physics prize a century ago for his work on the elementary charge of electricity and on the photoelectric effect. He succeeded in precisely determining the magnitude of the electron’s charge. Small electrically charged drops of oil were suspended between two metal plates where they were subjected to the downward force of gravity and the upward attraction of an electrical field. By measuring how the various drops of oil moved about, Millikan showed that their charge always was a multiple of a precisely determined charge—the electron’s charge.
Read Millikan's full Nobel Prize lecture here: https://www.nobelprize.org/.../phy.../1923/millikan/lecture/
Photo: Millikan in 1953-1954.
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