The waves of the sea, the sweeping curve of the sandy bay between the headlands, the outline of the hills, the shape of the clouds, all these are so many riddles of form, so many problems of morphology, and all of them the physicist can easily read and adequately solve: solving them by reference to their antecedent phenomena in the material system of mechanical forces to which they belong and to which we interpret them as being due.                                  D'Arcy Thompson's "On Growth and Form" Vol. 1, p 10