In human history to date, only a few species of large animal have been domesticated. In approximate order of their earliest domestication these are: dog, sheep, goat, pig, ox, yak, reindeer, water buffalo, horse, donkey, llama, alpaca, Bactrian camel and Arabian camel.
For instance at sea level and standard weather (29.9 Hg) a gauge vacuum of -25.9 Hg is equivalent to an absolute pressure of 4 Hg. In other words, the vacuum gauges that read, for example, -25.9 Hg at full vacuum is actually reporting 4 Hg, or 136 mbar. That is still in the low vacuum range.
Introduction to Pressure in Fluid Mechanics. 1  Pressure always acts inward normal to any surface (even imaginary surfaces as in a control volume). 2  Pressure is a normal stress, and hence has dimensions of force per unit area, or {ML-1T-2}. 3  Standard atmospheric pressure is 101.3 kPa (0.1013 MPa) or 14.69 psi.