University of Toronto, Toronto, Ontario: 16mm.
University of Waterloo Audiovisual Services Catalog.
"A revolution does not succeed until the opinions of members of the establishment are destroyed when public opinion sides with the revolutionaries. This applies for political revolutions, as well as for scientific revolutions. The platonic ideal of motion being uniform and circular remained with the scientific community until Johannes Kepler formulated the theory that the orbits of the planets are elliptical. For the earth sciences, the same resistance to change was evident when Alfred Wegener advanced his theory of continental drift in 1915. Recognition of his theory was slow; in the forties and fifties, more information was garnered, but not synthesized until the sixties, when Harry Hesse of Princeton made the connection between the mid-oceanic ridge system and its volcanic activity. In 1963, further advancements were made in the study of plate tectonics when paleomagnetic research revealed symmetry in movement of lava flows either side of the ridge crest. The theory of an original supercontinent, Pangeia, was becoming accepted. Tuzo Wilson briefly explains the theory of plate tectonics. Earth scientists still do not know what the force is that drives the plates on which the continents move; however, they expect that, some day soon, the Newton of plate tectonics will appear."