And as the moon rose higher the inessential houses began to melt away until gradually I became aware of the old island here that flowered once for Dutch sailors’ eyes — a fresh, green breast of the new world.
As Nick is examining his surrounding, he sees the human influence, the houses, as inessential parts to the vast landscape of the “old island”. For the original settlers, the “green breast of the new world” is a promise for a future with possibilities and excitement. For Nick, however, the land is a symbol for those who have succeeded and claimed the land, destroying the promise of a fruitful future for others.
The “inessential houses” also refers to the corruption of purity and nature in modern society because throughout the novel, houses symbolize materialism and wealth, both of which demoralize society.
To help improve the meaning of these lyrics, visit "The Great Gatsby (Chapter IX)" by F. Scott Fitzgerald and leave a comment on the lyrics box