That does help my understanding somewhat. It is not so much the path of water that confuses me. What I'm struggling to understand is that the actual amount of water above doesn't affect the force of pressure below - only the vertical distance.
@Angelo Farina
Thank you for the step by step explanation. I will look up the Pascal principle and read through your explanation again. By the way, what happens when there is flow? Is the water pressure at depth different in the spring caves of Florida than the caves of Mexico?
Yes, flow changes the pressure distribution in many different ways.
That's hydrodynamics, a part of science truly complex!
The two main phoenomena are governed by two scientists, Bernoulli and Navier.
Bernoully studies the flow inside a pipe of variable section, neglecting friction and losses. For example a Venturi tube, which is a conical restriction followed by a more gentle conical expansion.
Inside the throat of the venturi, velocity is increased significantly, and pressure drops dramatically. Energy is preserved, but converted from potential energy (pressure) to kinetic energy (velocity)..
After the throat, the flow slows down, and you come back with the same velocity and pressure as before the venturi.
Navier adds the evaluation of friction and losses, which become explicit in the Navier-Stokes differential equation.
Losses are due to viscosity, a property of water (and other fluids) which generetes tangential forces in presence of velocity gradients.
These tangential forces always oppose to the motion, resulting in a pressure loss along the pipe, even if its cross section is constant.
There are other phoenomena inside a fluid flow.
For example a submerged body is not subjected to an uniform pressure over its surface: in some parts the pressure will be higher, in some parts it will be smaller. The total resulting force will not be zero, it will be a vector pointing usually in the direction of flow.
But if the body has an asymmetric shape (like a wing), also a significant force in the transverse direction appears In case of a wing, the force in the direction of flow is called drag, the much larger force in transverse direction is called lift.
I tried to concentrate in a short post what requires a big book for being explained properly, so excuse me for the over-simplification and lack of rigour.