sentences:  So, for any particular measurement of pressure head, the height of a column of water will be about [133/9.8 = 13.6] 13.6 times taller than a column of mercury would be.So if a water column meter reads "13.6 cm H2O", then an equivalent measurement is "1.00 cm Hg".This example demonstrates why there is some confusion surrounding pressure head and its relationship to pressure.