  A simple viscometer consists of mineral water bottle and trink straw is used
to predict vicosity of water. A model is derived from Bernoulli's principle and
Poiseulli's law. Value about 0.374 - 0.707 cP is obtained for observation in
room temperature. About 10 minutes of observation time is needed to get the
data.
  Keywords: equation of continuity, Bernoulli's equation, viscosity
coefficient, Poiseulli flow.
