For a moment, Isabel's eyes met those of someone looking out of the window, a thin-faced woman with her hair done up in a bun. The woman began a smile, but stopped, as if conscious of somehow transgressing the conventions of isolation with which as city-dwellers we immure ourselves. The bus moved on, and zisabel felt a sudden desire to run alongside it, to wave to the woman, to aknowledge the unexpected exchange of fellow feeling between them. But she did mot, necause she never acted on these impulses, and because it might have puzzled or even frightened the other woman.