She knew nothing more unpardonable than to embarrass one's hostess.

She grew hard in contemplation of it.

Nothing justified it;--nothing.
A few girls were still coming from the candy factory.

Miss Osborne's car had crossed the bridge and was speeding toward her beautiful home up the river--just the home for a garden party.

The last group of girls, going along very slowly, had to step back for the machine to rush by.
Katie forgot her own grievance in wondering about those girls who had waited for the Osborne car to pass.
She knew where Miss Osborne was going, where and how she lived; she was wondering where the girls not enjoying the breeze always to be found in motoring were going, what they would do when they got there, and what they thought of the efforts to help them "manage better" on their dollar or less a day.
It made her rise and return to Ann.
Ann, too, was looking across the river at the girls who had given Miss Osborne right of way.