This is a misapprehension. Springs are on hillsides, not hilltops. Basically, imagine there are two surfaces: the ground, and the water table. In some places, usually on hillsides, the water table will intersect the surface. Where that happens, a spring will exist.
But that water has to be under pressure for this to happen – this is known as the hydrological gradient. Water flows down hill on the surface, and down gradient under ground. In order for there to be pressure on the water, enough to force it out a hillside, the water table somewhere in the hill needs to be physically higher in altitude than the spring.
In other words, it rains on top of the hill, and the rain soaks into the ground. That water wants to flow downhill, so it flows out of the ground on the sides of the hills. But this means a spring will never flow from the top of a hill.
Aren’t ancient wells often based on where springs were? Springs are often at the top of hills, aren’t they?
This is a misapprehension. Springs are on hillsides, not hilltops. Basically, imagine there are two surfaces: the ground, and the water table. In some places, usually on hillsides, the water table will intersect the surface. Where that happens, a spring will exist.
But that water has to be under pressure for this to happen – this is known as the hydrological gradient. Water flows down hill on the surface, and down gradient under ground. In order for there to be pressure on the water, enough to force it out a hillside, the water table somewhere in the hill needs to be physically higher in altitude than the spring.
In other words, it rains on top of the hill, and the rain soaks into the ground. That water wants to flow downhill, so it flows out of the ground on the sides of the hills. But this means a spring will never flow from the top of a hill.