A set of one-dimensional models, previously derived for liquid jets, i
s generalized to viscous liquid bridges by applying suitably modified
boundary conditions at the anchoring disks. A linear analysis for smal
l-amplitude perturbations around the cylindrical static solution is pe
rformed. The oscillation frequencies and growth factors so obtained ar
e compared to the already known linear three-dimensional results for a
wide range in both the slenderness and viscosity. The relative error
of each model is studied in terms of the typical axial length. Good ag
reement is found for slender enough bridges. The existence of boundary
layers for weakly dissipative Liquid bridges in the context of one-di
mensional models is also discussed. (C) 1996 American Institute of Phy
sics.