  The wetting properties of solid substrates with macroscopic random roughness
are considered as a function of the microscopic contact angle of the wetting
liquid and its partial pressure in the surrounding gas phase. It is shown that
Wenzel prewetting, which has been recently predicted for a rather wide class of
roughness profiles derived from Gaussian random processes by a general
distortion procedure, should in fact be ubiquitous and prevail under even much
milder conditions. The well-known transition occurring at Wenzel's angle is
accompanied by a prewetting transition, at which a jump in the adsorbed liquid
volume occurs. This should be present on most surfaces bearing homogeneous,
isotropic random roughness.
