The kinetics of spreading of a liquid drop in a wedge or V-shaped groove, in a network of such grooves, and on a hydrophilic strip, is reexamined. The length of a droplet of volume $\Omega$ spreading in a wedge after a time $t$ is predicted to scale as ${\Omega }^{1∕5}{t}^{2∕5}$, and the height profile is predicted to be a parabola in the distance along the wedge. If the droplet is spreading radially in a sparse network of V-shaped grooves on a surface, the radius is predicted to scale as ${\Omega }^{1∕6}{t}^{1∕3}$, provided the liquid is completely contained within the grooves. A number of other results are also obtained.

• Received 11 November 2003

DOI:https://doi.org/10.1103/PhysRevE.69.041601