  In this thesis, a theoretical treatment of the relation between
electrophoretic velocity and the potential of the double layer of colloidal
particles is presented.
  Translators' note: The theory of electrophoresis is one of the foundational
topics that underpinned the development of colloid and surface science and
ranks with the famous Derjaguin-Landau-Verwey-Overbeek (DLVO) theory of
colloidal stability. J. Th. G. Overbeek ("Theo" to all who knew him) was the
first to develop a complete theoretical analysis of the electrophoretic motion
of a charged spherical particle under the influence of an external electric
field. This provided the theoretical framework for a widely used experimental
method to characterize the state of charge and particle size of small colloidal
particles. The solution of this problem required mastery of fluid mechanics,
colloidal electrostatics, statistical thermodynamics and transport theory in
addition to solid applied mathematics. Theo carried out this study as his
doctoral thesis under H.R. Kruyt at Utrecht University. The thesis, in Dutch,
was later published as a monograph. Given the important pedagogic value and
historical status of this work, we felt that it deserved to enjoy a wide
readership.
