hydrostatic bed

Hydrostatic \Hy`dro*stat"ic\, Hydrostatical \Hy`dro*stat"ic*al\,
   a. [Hydro-, 1 + Gr. ? causing to stand: cf. F. hydrostatique.
   See {Static}.]
   Of or relating to hydrostatics; pertaining to, or in
   accordance with, the principles of the equilibrium of fluids.
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         The first discovery made in hydrostatics since the time
         of Archimedes is due to Stevinus.        --Hallam.
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   {Hydrostatic balance}, a balance for weighing substances in
      water, for the purpose of ascertaining their specific
      gravities.

   {Hydrostatic bed}, a water bed.

   {Hydrostatic bellows}, an apparatus consisting of a
      water-tight bellowslike case with a long, upright tube,
      into which water may be poured to illustrate the
      hydrostatic paradox.

   {Hydrostatic paradox}, the proposition in hydrostatics that
      any quantity of water, however small, may be made to
      counterbalance any weight, however great; or the law of
      the equality of pressure of fluids in all directions.

   {Hydrostatic press}, a machine in which great force, with
      slow motion, is communicated to a large plunger by means
      of water forced into the cylinder in which it moves, by a
      forcing pump of small diameter, to which the power is
      applied, the principle involved being the same as in the
      hydrostatic bellows. Also called {hydraulic press}, and
      {Bramah press}. In the illustration, a is a pump with a
      small plunger b, which forces the water into the cylinder
      c, thus driving upward the large plunder d, which performs
      the reduced work, such as compressing cotton bales, etc.
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