As soon as Mrs. Ramsay dismisses herself from the party, Lily senses that "a sort of disintegration set in"--all of the others start going their separate ways. The subject of conversation reverts from poetry to politics.
Mrs. Ramsay walks upstairs, wanting a moment to herself after all of the dinner chatter. She wants to extract one thing from the dinner, perhaps the very essence of this gathering of people, to separate from the rest of her collection of memories, and she looks out the window at the branches of an elm tree to gain an impression of stillness, order, and stability. She feels as though the world is changing and, like the stroke of the Lighthouse, she uses the elm tree to ground herself in a feeling of constancy. She then finds the one thought of the dinner party, as fleeting as the party was, that provides the sense of stability she was looking for: she knows that the guests, for the rest of their lives, will have this memory of the party--Paul and Minta will revive their memory of the special evening even after Mrs. Ramsay has died. In this way, the party has a life extending far beyond its immediate and passing existence, and this comforts Mrs. Ramsay.
She enters the children's room, annoyed that Cam and James are still awake. Cam cannot fall asleep because she is frightened by a pig skull on the wall that James insists on keeping in the bedroom. Mrs. Ramsay covers the skull with her own shawl and lays in bed with Cam, speaking rhythmically to her of beautiful and comforting things until she falls asleep. She then walks over to James's bed, assuring him that the skull is still there. He asks her if they will go to the Lighthouse tomorrow, and she answers that they will go soon, on the next nice day. She is upset even with herself for raising his hopes, probably just for those hopes to be crushed by Mr. Ramsay and Charles Tansley.
As she walks to the stairs, she engages in an inner dialogue about her mixed feelings for Charles Tansley. When Mrs. Ramsay arrives at the top of the stairs, Prue looks up at her, proudly and reverently thinking, "That's my mother." Prue tells her that they will go down to the beach to watch the waves, and Mrs. Ramsay is suddenly filled with gaiety. Though she wants to accompany them, she feels a strong and undefinable need to stay at home. She goes into the other room, where Mr. Ramsay is reading.
Mrs. Ramsay has the sense of having entered the room for something that she wants, but she does not know what. She notices that her husband does not want to be disturbed. He is engrossed in a book by Sir Walter Scott (whom Charles Tansley had discussed over dinner, saying that no one read him anymore), obvously moved by it and rapidly flipping the pages. She knows that Mr. Ramsay is troubled by the idea that no one will read his own books, and this troubles her in turn. She resumes her knitting of the stocking.
Mrs. Ramsay thinks to herself that fame does not matter, and she once again feels that she has come here for something, not knowing what that thing is. She remembers the lines of a poem recited at dinner ("And all the lives we ever lived / And all the lives to be, / Are full of trees and changing leaves." She picks up a book, reading from different pages at random. She is roused by the sound of her husband slapping his thigh, and they look up at each other, silently communicating.
Mr. Ramsay, utterly engaged with the story, suddenly forgets his own failures and his quest for personal greatness. He is moved to tears by the death and sorrow of the characters. Stifling a desire to complain to his wife that young men did not admire him, he feels determined not to bother her and notices how peaceful she looks as she is reading. He reprimands himself for this feeling of domestic comfort and returns to his book.
As Mrs. Ramsay reads, she senses that Mr. Ramsay is watching her. He is glad that she no longer looks sad, and he is astonished by her beauty--but he doubts that she comprehends what she is reading.
Mrs. Ramsay finishes reading, and they begin a sparse conversation about Paul and Minta's engagement. During the moments of silence, Mrs. Ramsay wishes that her husband would say something, though she does sense their growing intimacy. He tells her that she will not finish the stocking tonight, and she agrees. In silence again, she realizes that he wants her to tell him that she loves him, but this is something that she finds herself unable to say. She stands and looks out the window, feeling that he is watching her and finding her beautiful. She turns to him and smiles, knowing that, although she has said nothing, he knows that she loves him. She tells him that he was right--it will be too wet tomorrow for a trip to the Lighthouse--and she knows that he can feel her love.
Mrs. Ramsay's reliance on the tree outside the window (standing tall like the Lighthouse, but much closer) to offer her a sense of stability and order is immediately reminiscent of the tree in Lily's painting, which has been an object of thought throughout the dinner. For Lily, this tree also represents order and stability. By moving it to the middle, she will create a composition of unity and balance, and this composition will be more likely to endure. She will combine all of the elements into a coherent picture, and her ability to do this expresses her artist's sense of control and order. This connection between Lily and Mrs. Ramsay, both looking to trees as representations of stability, is particularly important in light of the novel's conclusion, when it seems that only Lily's ability to fulfill her artistic vision from ten years earlier can save the Ramsays. Lily's later completion of the painting is evidence that something from the night of the dinner party has staying power, just as Mrs. Ramsay had wished, even if that permanence exists only through memory and artistic representation.
The symbolic power of the tree gains further resonance through Mrs. Ramsay's recitation of lines from Charles Elton's poem, "Luriana Lurilee"--"And all the lives we ever lived / And all the lives to be, / Are full of trees and changing leaves." Trees (like water and like nature in general) dichotomously represent both stability and change. Though the deciduous tree itself remains fixed, the leaves on its branches annually repeat the life-death cycle.
Water, too, is a common symbol of the tension between constancy and change. Mrs. Ramsay is comforted by the water's rhythmic lapping against the shore, yet it is also the force that causes the erosion of land over time. Its constancy gives it the power to cause decay. The dual representative purpose of the tree and of water indicates, more generally, that the Ramsays cannot escape the realities of human existence, where the greatest moments last only as long as memory keeps them.
The boar skull in the nursery, in particular the fact that Mrs. Ramsay covers it with her shawl, provides deep and immediate symbolism as this section of the novel nears its conclusion. "The Window" is in large part about the characters' fear of the passage of time and the disappointment, suffering, and destruction that naturally accompany the process of aging. The skull is a clear symbol of the decay of time. The animal from which it came is now nothing more than a skull hanging in the children's room, without meaning or purpose. Its placement in the nursery is significant given Mrs. Ramsay's preoccupation with wanting her children to stay young and to avoid all of the suffering of age and experience. This skull, which so frightens Cam, represents the inevitable end of life and meaning. The animal itself is not remembered through the skull anymore, and Mrs. Ramsay cloaks the skull and its awful significance with her own protective clothing.
When Mrs. Ramsay covers it with her shawl, it parallels her attempts to soothe her children with her warmth and beauty. Just as she tries to shield them from harsh reality (the fact James will not go to the Lighthouse, for instance), she tries to shield them from this grotesquely realistic image. Even so, as she tells James, the skull still hangs beneath the shawl; she can hide it, but she cannot fully erase its looming presence, since the skull still takes up its share of space in the room and in their lives. Later, in the "Time Passes" interlude, the shawl slowly unravels from the skull as the ravages of time take over, with no one to resist or hide the decay. As the house is taken over by natural life processes such as overgrowth and decay, the skull as symbol of death and disintegration is slowly exposed.
The silent communication that occurs between Mr. and Mrs. Ramsay throughout the book (and at the end of Chapter XIX, in particular) is perhaps the most compelling expression in the novel of the fluidity of consciousness. The married couple seem to ask and answer one another's silent questions without any conscious effort. It is fitting that Mrs. Ramsay should retreat into her self as a silent and invisible wedge-shaped darkness, not able to express or openly reveal her feelings, during these times of deepest expression.