In its apparent laziness, in its awful deliberation, and its quick spasms of wrath, it was more like the work of waves than of men; and our high platform's gentle sway and glide was exactly the motion of a ship drifting with us toward that shore.

Sway is a common noun, of the third person, singular number, neuter gender, and objective case; and is governed by exert; according to Rule 5th, which says, "A noun or a pronoun made the object of an active-transitive verb or participle, is governed by it in the objective case."