[Oil-Drop Experiment] A New Modification of the Cloud Method of Determining the Electrical Charge [e] and the most Probable Value of that Charge. By Prof. R.A. Millikan, University of Chicago: [in] The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science [Sixth Series] February 1910.

R A Millikan announces his oil-drop experiment which defined the elementary electrical charge on an electron. Single journal article from Volume 19, No. 110 of the Philosophical Magazine (February 1910) which subsequently gained him the Nobel Prize for Physics in 1923.

Bound together as Volume LXVII - Sixth Series, Volume 19 - for the period January to June 1910 with original blue Journal front wrapper from January 1910 (Vol 19, No.109) and back wrapper from June 1910 (Vol 19, No.114). This volume has been deaccessioned from the library of Venice’s Istituto Veneto Scienze Lettere e DArti - small oval library stamps on blue front wrapper, at the tail of the title page and final page of Index at rear and elsewhere throughout. Stamp ‘Sala Palch’ and ‘No. 369’ on front page of each monthly edition. Bound in half sheep over handsome marbled boards, gilt decoration to spine and Shelf Mark ‘Periodici B171’ at the tail of the backstrip. Some browning to margins of end leaves, otherwise a near fine copy.

Millikan’s ground breaking paper occupies pp. 209-228, of Vol. 19, No. 110 of the Sixth Series (February 1910) of this volume. Between 1909 and 1910 Millikan, together with his graduate student Harvey Fletcher, refined experimental methods that elucidated a value for e, the charge on a single electron, to within 0.5% of the modern accepted value. Not without controversy over his selection of results, this work enabled the mass of the electron to be determined, as also a value for Avogadro’s number; and showed that electrical charge is quantized. Millikan’s result enabled new avenues in physical and chemical researches fundamental to our present understanding.