WEGENER’S 1920 BOOK

Wegener is at his most buoyant in the 2nd edition. This is because he thinks he has the crucial experimental results that prove his theory. Also, his father-in-law, Köppen, skeptical in 1912 when he advised Wegener not to stray from being a meteorologist, is now enthusiastically onboard.

Wegener’s 1920 book is now available in English translation (Rance, 2014). Wegener begins (Chapter 1) by downgrading to hypotheses the long-cherished theories of: crustal contraction, which is inadequate to explain Alpine overthrusts, bridging continents, which is contradicted by isostasy, and permanence, which his lateral displacement theory replaces. In this edition, unlike what becomes the focus of the later editions, Wegener is little concerned with what drives the lateral movement of continents. He briefly mentions pole flight and westward drift mechanisms that others have conceived and insists that: "Even should these mechanical ideas turn out to be substantially wrong, the correctness of the displacement theory would in no way be called into question. For if the observations show that movements have taken place, we must accept them for what they are whether we can explain them today or not." So a triumphal "Proof of the continental displacements by astronomical determinations" (Chapter 7) ends the second edition.