The correct answer is: "The land's sharp features seemed to be/The Century's corpse outleant".
When one refers to nature, it is most commonly in regard to one's non-artificial surroundings.
Addressing the "Forces of Nature" might refer to the cause of everything as it is disregarding the influence of rational beings, such as humans.
In this sense, the primordial and untouched shaping of a lot of land is the making of the forces of nature being acknowledged by the reader.