Comment on “Effect of gravity on contact angle: A theoretical investigation” [J. Chem. Phys. 109, 3651 (1998)]

In a recent theoretical analysis by Ward and Sasges [J. Chem. Phys. 109, 3651 (1998)] the experimentally observed difference in contact angle at the upper and lower meniscus in a capillary is ascribed to the height dependence of the three surface tensions that determine the contact angle through Young’s law. We argue that their analysis contains an error and that in equilibrium the contact angles should be equal.