Continental drift my lecturers why he was not talking to us about continental drift and I was told, sneeringly, that if I could prove there was a force that could move continents, then he might think about it. The idea was moonshine, I was informed." As late as 1953 – just five years before Carey introduced the theory of plate tectonics – the theory of continental drift was rejected by the physicist Scheidegger on the following grounds. From the 1930s to the late 1950s, works by Vening-Meinesz, Holmes, Umbgrove, and numerous others outlined concepts that were close or nearly identical to modern
Continental Divide of the Americas such as the International Hydrographic Organization add a sixth: Canada's Northwest Passage basin. Using just the five, there are four secondary continental divides and three secondary triple points, the two mentioned previously and a third near Hibbing, Minnesota, where the Northern Divide intersects the Saint Lawrence Seaway divide. Since there is no true consensus on what a continental divide is, there is no real agreement on where the secondary triple points are located. However, the main Continental Divide described in this article is a far more distinctive geological feature than the others and its two main triple points are much