Choose two images and explain how the author creates a certain mood and tone with these images in The Great Gatsby.
We walked through a high hallway into a bright rose-colored space, fragilely bound into the house by French windows at either end. The windows were ajar and gleaming white against the fresh grass outside that seemed to grow a littlt 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 only completely stationary object in the room was an enormous couch on which two young women were buoyed up as though upon an anchored balloon. They were both in white and their dresses were rippling and fluttering as if they had just been blown back in after a short flight around the house. I must have stood for a few moments listening to the whip and snap of the curtains and the groan of a picture on the wall. Then there was a boom as Tom Buchanan shut the rear windows and the caught wind died out about the room and the curtains and rugs and the two young women ballooned slowly to the floor
In the second paragraph you cite from The Great Gatsby, Tom is the killjoy, which is appropriate since he will play the same role when he smacks Myrtle and when he puts a stop to the flirtation, as he thinks of it, of Daisy and Gatsby. He causes a shift in this passage.
The writer, or more accurately, the speaker, relates the shift, however. Overall, he accomplishes the shift by reversing the imagery.
The white dresses are "fluttering" and "rippling" as if just returning from a "flight," and the women are "buoyed up" as if they are floating in midair by an "anchored balloon." The diction contributes to the visual imagery. But the "whip" and "snap" and "groan" (diction contributing to sound imagery) become a "boom" and the shift occurs. Instead of the light, airy imagery, and in addition to "boom," we get "shut," "caught," "died," and "slowly to the floor." This juxtaposition--placing opposites side by side--of imagery, contributed to by the diction, enhances the effect of the shift. The speaker reverses the imagery, and thereby reverses the tone.
Of course, the light, poignant picture of the women floating is an illusion. And like other illusion in The Great Gatsby, it is brought to an abrupt end.
In my opinion, what the author is trying to do in this passage is to make a sort of fairy tale mood. I think that he is trying to do this to suggest that there is something not completely real about the characters and their surroundings. None of the people in the house, other than Nick, is really a solid person -- all of them have flaws and are not as nice as they seem.
I think you can see the author creating this image with his talk of the sea (insubstantial, always changing) and of the women who are floating in the air.