When Nick describes his first meeting with Myrtle Wilson in chapter 2, he says the following about her:
[She had an] immediately perceptible vitality about her as if the nerves of her body were continually smoldering.
This is particularly interesting given Nick's description of Myrtle's husband, George, on whom she has been cheating with Tom Buchanan. Nick says the following about the sight of George:
[He] mingl[es] immediately with the cement color of the walls. A white ashen dust veiled his dark suit and his pale hair as it veiled everything in the vicinity—except his wife.
Thus, Myrtle is described as "smoldering," as though she is constantly burning, while her husband is described as ashen and pale, as though he has been burned to ash. Nick also says the following about George: "When he saw [Nick and Tom] a damp gleam of hope sprang into his light blue eyes." George is fair and bland, and Myrtle "walks through her husband as if he were a ghost." She is vital and alive, almost aggressively so, while even her husband's eyes are light and faint in color. Nick's choice of the word "damp" to describe George's hope also illustrates how different the two are from one another: Myrtle smolders, while George is damp; she is even described as having a "thickish figure," and her husband is "anaemic," which can refer to his lack of vitality and his lack of substance. She is physically substantial, and he is not; she is vital, and he seems weak; she burns, but he is burned.