If you have ever spilled ice cubes on your kitchen counter, you notice that they slide around quite easily. This is just like the continental plates floating around on top of the Earth’s mantle. In the 1600 and 1700s, English philosopher and scientist Francis Bacon and American statesman and scientist Benjamin Franklin noticed that the two continents on either side of the Atlantic Ocean (South America and Africa) seemed to fit together. Back then, sliding or drifting tectonic plates was unknown. This theory of a moving Earth was first proposed as continental drift in 1912 by a German scientist named Alfred Wegener. He noticed that the continents appeared to fit together like a giant jigsaw puzzle.