The Croonian Lecture - Transport of substances in plants

Abstract

When the Royal Society—now many years ago—did the late Dr Joly and me the honour of publishing our first paper on the ascent of sap (Dixon and Joly 1894, 1895), it was not difficult to make a first approximation as to the mechanism, and the energy conditions, availed of by plants in lifting water from the soil to their leaves. The driving force was to be sought in the vapour-pressure difference obtaining in the spaces surrounding the roots and the leaves (Dixon 1897).