The valley of ashes is bounded on one side by a small foul river, and, when the drawbridge is up to let barges through, the passengers on waiting trains can stare at the dismal scene for as long as half an hour
In this passage, Fitzgerald is explained the contrast between the rich and poor. For example, in order for the rich to get to the mansions or to get into the city they HAVE to go through the Valley of the Ashes, which is described as a very grey and deathly place. The image that comes to mind when thinking about the rich going through the valley of the ashes is when your on the road and a homeless person is knocking on your window asking for money. You act like the person isn’t there, but in reality you are put in a very awkward position.
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