Read it through once

She had behaved beautifully--and in beautiful behaviour she was unsurpassed--during the call on Mrs. Welland; but Newland knew (and his betrothed doubtless guessed) that all through the visit she and Janey were nervously on the watch for Madame Olenska's possible intrusion; and when they left the house together she had permitted herself to say to her son: "I'm thankful that Augusta Welland received us alone."