Caltech Library News

Robert A. Millikan's oil drop experiment is known to every student of physics

Photo ID 1.22-8

Now his actual notebooks, in which he meticulously recorded his painstaking measurements, may be viewed online. Millikan began his attempt to measure the charge on the electron in 1907. The only two lab notebooks which he kept until the end of this life, and which are now in the Caltech Archives, record his conclusive work on this problem during the period from October 1911 through April 1912. Millikan won the Nobel Prize in physics in 1923. The notebooks are presented in digital facsimile in the Archives' new repository titled Lab Notes Online within the Caltech Libraries' Digital Collections (CODA). Additional lab notes and data by others will be added to this repository over time.