  The effect of 'bridge splitting' is considered in the case of capillary
adhesion: for a fixed total volume of liquid, does having more capillary
bridges increase the total adhesion force? Previous studies have shown that the
capillary-induced adhesion force between two planar surfaces is only
substantially enhanced by bridge splitting in specific circumstances. Here this
previous result is reconsidered, and it is shown that bridge splitting may
significantly increase the adhesion forces when one of the surfaces is rough.
The resistance to shear is also examined, and it is shown that bridge splitting
on a rough surface can lead to a steady capillary-induced shear force that
scales linearly with translation velocity, even in the absence of contact-line
pinning.
