How to picture groundwater flow beneath the surface.

Analogues and analogies.  Standard dictionaries define these as a comparison, correspondence, or similarity between one thing and another, that can apply to concepts, ideas or physical entities. They are tools, used to illustrate concepts, particularly abstract ideas, to help explain phenomena or theories. Science makes frequent use of analogies. It does so because many phenomena that it attempts to investigate and explain extend beyond normal human experience, beyond what is visible to the unaided eye, beyond what we can touch.  Well-chosen analogies can help us understand the universe without, and the universe within. Continue reading →