She understood.

She-- And her thoughts swung back like the returning tide to Siward, and her heart began heavily again, and the slightly faint sensation returned.
She passed her ungloved, unsteady fingers across her eyelids and forehead, looking up and around.

The major and Howard had disappeared; Plank, beside her, sat staring stupidly into his empty wine-glass.
"Isn't Mrs.Ferrall coming ?" she said wearily.
Plank gathered his cumbersome bulk and stood up, trying to see through the entrance into the ball-room.

After a moment he said: "They're in there, talking to Marion.

It's a good chance to make our adieux." As they passed out of the supper-room Sylvia paused behind Agatha's chair and bent over her.