Geology
Henry Darcy was the 19th century
French hydraulic
engineer who is responsible for the field of
groundwater hydrology as a quantitative science. Darcy observed that the loss in pressure head of fluid flowing through a porous medium (as measured by manometers), was correlated with the distance the water flowed. Darcy's Law can be summarized
dh
Q = -K ---- A
dl
where
Q is the flow rate,
A is the cross sectional area perpindicular to the flow area,
dh is the pressure loss (measured in meters of water),
dl is the distance between observing points and
K is an
empirical constant known as the
hydraulic conductivity.