The railway station is crowded with volunteers supporting the Slavic movement. Koznyshev learns that Vronsky is on the train, having volunteered and now headed out to war. Someone makes a speech, and the crowd grows wild in support of the volunteers. Oblonsky sees Koznyshev and encourages him to make a speech as well, but Koznyshev says he’s leaving to visit Levin at Levin’s country place. Oblonsky tells Koznyshev to say hello to Dolly and to tell her that he’s been appointed to the post that he’d wanted; he also says it’s too bad that Koznyshev is leaving that day, since Oblonsky is throwing a dinner party.
Throngs of people are leaving to fight for the Slavs—including Vronsky himself, though Tolstoy only lets the reader see him from Koznyshev’s perspective, so the reader can’t tell exactly how Vronsky feels. Oblonsky is so estranged from Dolly that he is sending her messages through friends rather than communicating himself with her; his life now revolves in his Petersburg social circle, not in his household.
When Oblonsky sees Vronsky, he forgets about the Vronsky who sobbed over Anna’s dead body and only sees Vronsky the military hero. The woman chatting with Koznyshev points out Vronsky; Vronsky turns and raises his hat, his face stony and sad, haggard with an unspoken grief.
Tolstoy only mentions Vronsky’s grief over Anna’s death in passing, instead focusing the description on Vronsky the soldier, but Vronsky’s haggard appearance shows that his grief runs deep, even if it’s unspoken. The very fact that it’s unspoken may indeed demonstrate the actual depth of his despair due to Tolstoy’s mistrust of verbal communication. It appears that Anna was right in her belief that her death would bond Vronsky to her more deeply than anything else. And Vronsky’s act of going off to war suggests that he too may be putting himself in the way of death in response. Anna and Vronsky’s relationship, founded on secrets, has always revolved around emptiness, and now revolves around death.