Found on a Mountaintop

I read a book one time about a geologist from the 1600's named Nicholas Steno, who spent a good portion of his life trying put together the geologic history of the earth through its rock strata. Some scientists had found several seashells on a mountaintop, and he set out to prove that they weren't put there because of the biblical flood (Noah, the animals came two-by-two, etc.) like most people believed at the time, but rather because the earth's plates had shifted and the mountaintop used to be underwater.

This same guy also discovered that animals have tear ducts just like humans.

I wish I lived back then.