  We consider theoretically liquid rise against gravity in capillaries with
height-dependent cross-section. For a conical capillary made from a hydrophobic
surface and dipped in a liquid reservoir, the equilibrium liquid height depends
on the cone opening angle $\alpha$, the Young-Dupr\'{e} contact angle $\theta$,
the cone radius at the reservoir's level $R_0$ and the capillary length
$\kappa^{-1}$. As $\alpha$ is increased from zero, the meniscus' position
changes continuously until, when $\alpha$ attains a critical value, the
meniscus jumps to the bottom of the capillary. For hydrophilic surfaces the
meniscus jumps to the top. The same liquid height discontinuuity can be
achieved with electrowetting with no mechanical motion. Essentially the same
behavior is found for two tilted surfaces. We further consider capillaries with
periodic radius modulations, and find that there are few competing minima for
the meniscus location. A transition from one to another can be performed by the
use of electrowetting. The phenomenon discussed here may find uses in
microfluidic applications requiring the transport small amounts of water
``quanta'' (volume$<1$ nL) in a regular fashion.
