  We propose a model to understand periodic oscillations relevant to the origin
of mesoscopic channels formed during a Langmuir-Blodgett deposition observed in
recent experiments \{M. Gleiche, L.F. Chi, and H. Fuchs, Nature {\bf 403}, 173
(2000)\}. We numerically study one-dimensional flow of a van der Waals fluid
near its discontinuous liquid-gas transition and find that steady-state flow
becomes unstable in the vicinity of the phase transition. Instabilities leading
to complex periodic density-oscillations are demonstrated at some suitably
chosen sets of parameters.
