The American physicist Robert Andrews Millikan (1868-1953) measured the charge of the electron, proved the validity of Albert Einstein's photoelectric effect equation, and carried out pioneering cosmic-ray experiments.

The second son of a Congregational minister of Scotch-Irish ancestry, R. A. Millikan was born on March 22, 1868. He entered the preparatory department of Oberlin College in 1886.

The only physics Millikan studied during his first 2 years at Oberlin was in a 12-week course, which he later described as "a complete loss." It therefore came as a complete surprise when his Greek professor asked him to teach the elementary physics course. Encouraged by the professor's remark that "anyone who can do well in my Greek can teach physics," Millikan accepted the challenge and spent the summer reading an elementary textbook and working the problems in it. This was Millikan's real introduction to physics and the origin of a conviction he held throughout...