... reveal the extent and duration of Emma's dislike. There are many others that hint at it; I've taken a selection only of the least ambiguous snippets.

Ch 10: "Do you know Miss Bates's niece? That is, I know you must have seen her a hundred times -- but are you acquainted?"
"Oh! yes; we are always forced to be acquainted whenever she comes to Highbury. "

Ch 12: And she talked in this way so long and successfully that, when forced to give her attention again to her father and sister, she had nothing worse to hear than Isabella's kind inquiry after Jane Fairfax; -- and Jane Fairfax, though no great favourite with her in general, she was at that moment very happy to assist in praising.

Ch. 20: "Emma was sorry to have to pay civilities to a person she did not like through three long months! to be always doing more than she wished, and less than she ought! Why she did not like Jane Fairfax might be a difficult question to answer; Mr. Knightley had once told her it was because she saw in her the really accomplished young woman, which she wanted to be thought herself; and though the accusation had been eagerly refuted at the time, there were moments of self-examination in which her conscience could not quite acquit her. ...
It was a dislike so little just -- every imputed fault was so magnified by fancy, that she never saw Jane Fairfax the first time after any considerable absence, without feeling that she had injured her; and now, when the due visit was paid, on her arrival, after a two years' interval, she was particularly struck with the very appearance and manners, which for those two whole years she had been depreciating. "

Ch. 21: Mr. Knightley praises Emma for her attentions to Jane, is bitterly disappointed when she reveals that she was actually digging for dirt.

Ch. 31: "Oh! the coldness of a Jane Fairfax! Harriet is worth a hundred such: and for a wife -- a sensible man's wife -- it is invaluable. "

Ch. 34: "she could now invite the very person whom she really wanted to make the eighth, Jane Fairfax. Since her last conversation with Mrs. Weston and Mr. Knightley, she was more conscience-stricken about Jane Fairfax than she had often been. Mr. Knightley's words dwelt with her. He had said that Jane Fairfax received attentions from Mrs. Elton which nobody else paid her. "

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