Developments in lubrication - the thinning film

Research on lubrication is as active today as it has ever been during the 20th century, yet it is well over a hundred years since Osborne Reynolds exposed the fundamental nature of fluid-film lubrication. Since 1886 the effective film thickness in lubricated machine components has been reduced by a few orders of magnitude and the reasons for this `thinning film' are reviewed on the occasion of the 10th anniversary of the Institute of Physics Tribology Group and the 25th anniversary of the publication of the Jost Report.