Two young women were buoyed up as though upon an anchored balloon.
Fitzgerald uses the light and airy language as a metaphor for the social mobility that these two young women enjoy. As members of the aristocracy, they are at the top of the social hierarchy, and they run no danger of losing their place as they are “anchored on a balloon” that keeps them at the highest level. At the same time, their apparent weightlessness, which can be attributed to the complete absence of burdens and hard work in their lives, allows them to come and go as they please to and from any place in society, as all the doors are open to young, beautiful, wealthy white girls.
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