Robert A. Millikan and the Oil Drop Experiment

In 2018, we celebrated the sesquicentennial birthday of Robert A. Millikan, a Nobel laureate in physics who worked among the greats such as Niels Bohr and Albert Einstein. His name, however, is perhaps not as widely known. He was born in 1868 in Morrison, IL, and moved with his family to the small town of Maquoketa, IA, at age nine. It was in this tiny Iowan town that Millikan spent his foundational years. He passed the time playing baseball and cooling off in the Maquoketa River. Millikan’s interest in experimentation showed early on. Local changes to the rules of baseball sparked controversy over a new type of pitch: the curve ball. Silas Millikan, Robert’s father, was a college-educated man and staunchly maintained that the curve ball was simply an optical illusion, but young Millikan knew better. With the help of brothers and cousins, Millikan set up a simple experiment to prove the point. Millikan and his family set up three poles in a line out in the yard and repeatedly pitched curveballs at one another. With careful observation, Silas could see the ball travel straight along the first two poles, then visibly curve and land on the opposite side of the third. This experiment was a small victory for Millikan, and only foreshadowed his later investment in scientific study.