Where on earth do we often find examples of metamorphism due to chemically active
fluids?

Metamorphism occurs at temperatures and pressures higher than 200oC and 300 MPa. Rocks can be subjected to these higher temperatures and pressures as they are buried deeper in the Earth. Such burial usually takes place as a result of tectonic processes such as continental collisions or subduction

Early in the story when tom finds an indian skull in the woods which he kicks in temper. the devil then makes his appearance and, as tom surveys him, he notices that the devil is neither "negro" nor "indian." in fact, he has a "swarthy" complexion and is "begrimed with soot."