43. One of the most significant traces of this great disaster are rocks called “erratic blocks.” Thus are named granite rocks that are found isolated in plains reposing upon tertiary beds, and in the midst of diluvial rocks, sometimes many hundred of miles from mountains whence they have been torn. It is evident that they can have been transported so great a distance only by the violence of a current. *
* It is one of these blocks, evidently by its composition coming from the mountains of Norway, which serves as the pedestal to the statue of Peter the Great at St. Petersburg.