How does the author use symbolism in the nonfiction book, Underland?

The whirlpool represents the abyss or the void. Edgar Allan Poe wrote about the famous whirlpool that lies just off the coast of the Lofoten shore, near where MacFarlane travels in Chapters 8 and 9. Poe used the whirlpool as a symbol of the abyss. Poe depicts the whirlpool as an irresistible force that pulls people and boats toward it. MacFarlane uses the idea of a whirlpool as an abyss too, mentioning several times in Underland the attraction he has to being pulled downward, into the swirling underland. He mentions a similar feeling as he descends into a moulin atop a glacier in Greenland. "Such structures captive us because of the distant tractions they exert, the event horizons they establish," MacFarlane writes (308).