Wise people understand this, and everybody is more influenced by it than they know, perhaps.

Polly was not very wise, but she felt that every one about her found something more attractive than usual in her and modestly attributed Tom's devotion, Sydney's interest, and Frank's undisguised admiration, to the new bonnet or, more likely, to that delightful combination of cashmere, silk, and swan's-down, which, like Charity's mantle, seemed to cover a multitude of sins in other people's eyes and exalt the little music teacher to the rank of a young lady.
Polly scoffed at this sort of thing sometimes, but to-night she accepted it without a murmur rather enjoyed it in fact, let her bracelets shine before the eyes of all men, and felt that it was good to seem comely in their sight.

She forgot one thing, however: that her own happy spirits gave the crowning charm to a picture which every one liked to see a blithe young girl enjoying herself with all her heart.

The music and the light, costume and company, excited Polly and made many things possible which at most times she would never have thought of saying or doing.

She did not mean to flirt, but somehow "it flirted itself" and she could n't help it, for, once started, it was hard to stop, with Tom goading her on, and Sydney looking at her with that new interest in his eyes.
Polly's flirting was such a very mild imitation of the fashionable thing that Trix & Co.