Just FYI, the modern theory of plate tectonics dates back to the 1960s but by that time it had been centuries since people first noticed that some continents looked like they had fit together and then moved apart.
Wikipedia says that in 1596,
Abraham Ortelius in his work Thesaurus Geographicus ... suggested that the Americas were "torn away from Europe and Africa ... by earthquakes and floods" and went on to say: "The vestiges of the rupture reveal themselves if someone brings forward a map of the world and considers carefully the coasts of the three [continents]."