Subduction of oceanic lithosphere at the trenches can act like a bulldozer to produce

Subduction of 'oceanic lithosphere' at the trenches can act like a 'bulldozer' to produce an accretionary wedge.

Explanation:

The action of subduction subsequently results in a gradual layering up of material on 'both sides of the plate'. This process of layering up of the material from the plates is called as accretion. When a lighter plate undergoes subduction, it not only subducts but also lifts up the other plate to a certain extent. This action directly results in the formation of an 'accretionary wedge'.

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."