The Lost Worlds of Planet Earth Ortelius hypothesized the idea that land masses may have been connected in the past, Alfred Wegener who hypothesized the idea of a super-continent Pangaea and continental drift despite the prevailing idea of flooded land-bridges at the time, and Bruce C. Heezen and Marie Tharp who discovered the Mid-Atlantic Ridge that supported the theory of plate tectonics. Tyson describes how the landmasses of the earth lay atop the mantle, which moves due to the motion and heat of the earth's outer and inner core. Tyson moves on to explain the asteroid impact that initiated the Cretaceous–Paleogene extinction event, leaving small mammals
Canon of the Mass in all liturgical texts. Fortescue remarked that the medieval explanations are interesting as showing with what reverence people studied the text of the Canon and how, when every one had forgotten the original reasons for its forms, they still kept the conviction that the Mass is full of venerable mysteries and that all its clauses mean more than common expressions. He added that in this conviction the sometimes naive medieval interpreters were eminently right. Canon of the Mass Canon of the Mass (Latin: "Canon Missæ", "Canon Actionis") is the name given in the Roman Missal, from the first typical edition