The first visual image is the juxtaposition of East and West Egg. Nick lives in West Egg, the less sophisticated of the two. From his position in West Egg, Nick could see across the bay to East Egg as it "glittered across water." This comparison will later be eclipsed by the more dramatic juxtaposition of West Egg and the Valley of Ashes (Chapter 2). These polarities symbolize the distinction between the rich and the poor, with the implications that there is a real physical division between the two. That is, it might be impossible for the poor to move up to the world of the rich; thus, the American Dream is an illusion.
When Nick goes to see Tom and Daisy, he is surprised that their house is more luxurious than he'd thought. As we see later in the novel, Gatsby's obsession with Daisy is wrapped up with the idea of money. This is underscored in the descriptions of Daisy's home:
The windows were ajar and gleaming white against the fresh grass outside that seemed to grow a little way into the house. A breeze blew through the room, blew curtains in at one end and out the other like pale flags, twisting them up toward the frosted wedding-cake of the ceiling, and then rippled over the wine-colored rug, making a shadow on it as wind does on the sea.
The images concerning taste are indirectly alluded to: the half-acre of pungent roses outside of Daisy and Tom's house, the surprisingly good claret (wine) Nick is drinking, and the visual images of food such as the "wine-colored rug" and the "frosted wedding cake of the ceiling." All of these express associations of affluence, particularly relating to East Egg, Tom, and Daisy.
The final visual image takes us back to the juxtaposition of West Egg and the more luxurious East Egg. When Nick is back home, he notices who he thinks must be Gatsby, standing outside, looking across the bay to East Egg. He decides not to call out to him, observing:
But I didn’t call to him, for he gave a sudden intimation that he was content to be alone—he stretched out his arms toward the dark water in a curious way, and, far as I was from him, I could have sworn he was trembling. Involuntarily I glanced seaward—and distinguished nothing except a single green light, minute and far away, that might have been the end of a dock.
The green light is an important and recurring image in the novel. This light, what Gatsby is focusing on and reaching toward, is the light at the end of Daisy's dock. The color green becomes a beacon to Gatsby; it symbolizes Daisy. And, by Fitzgerald's design, this color of Gatsby's American Dream is also the color of money. Gatsby consciously associates the two: Daisy and money.