What does "floating rounds of cocktails" mean?

Hard to say precisely what Fitzgerald means-- the cocktails are 'floating' on the waiters' trays, or the guests, carrying cocktails, are 'floating' from one conversation group to another. 'Rounds' are consecutive servings of drinks to participants, but could also here refer to the milling of the guests.

Or perhaps the bar is inside, but the smell of cocktails moves into the garden outside too.

Mister MicawberHard to say precisely what Fitzgerald means-- the cocktails are 'floating' on the waiters' trays, or the guests, carrying cocktails, are 'floating' from one conversation group to another. 'Rounds' are consecutive servings of drinks to participants, but could also here refer to the milling of the guests.

Thank you very much.

It could be foreshadowing of Gatsby's death later in the novel, as he is found 'floating' in his swimming pool. (Sorry if this ruined the book for you haha).
It also shows how 'illegitimate' Nick considers the 'staff' to be, because he thinks he is of a higher social class, even though he isn't really.

The word "floating" might have been current slang at the time the book was written, the meaning now all but forgotten. The sense might have been related in some way to phrases that are still with us, like: "she was literally floating from person to person at the party, drink in hand," or "there's a rumor that has been floating around about her," or "I was so happy I was floating on air," etc.

Metaphor - reflects Nick's perception of the magical, enchanted atmosphere at Gatsby's party. Just as magical objects may float in the air, so too do the trays of cocktails seem to magically be drifting dreamily through the party and guests, when in reality waiters are carrying them. Fitzgerald uses the word "floating" to convey that Nick felt enchanted by the effortless, magical atmosphere of G