Appendix D—Notes on Darcy's law and permeability

In any effort to establish nomenclature relating to the flow of fluids through porous media it would seem well first to consider the history of the development of our concepts and of the terms or expressions involved. Only in this way can precedent rightfully be honored and at the same time duplicating expressions be eliminated and the remaining more useful terms clarified. Then, proceeding with a foresight lined up with recent advances, we may hope to anticipate the needs of the future.