If able to suggest a hint, Isabella could never understand it.

In this distress, the intended departure of the Tilney family became her chief consolation; their journey into Gloucestershire was to take place within a few days, and Captain Tilney's removal would at least restore peace to every heart but his own.

But Captain Tilney had at present no intention of removing; he was not to be of the party to Northanger; he was to continue at Bath.
When Catherine knew this, her resolution was directly made.

She spoke to Henry Tilney on the subject, regretting his brother's evident partiality for Miss Thorpe, and entreating him to make known her prior engagement.
"My brother does know it," was Henry's answer.
"Does he?
Then why does he stay here ?" He made no reply, and was beginning to talk of something else; but she eagerly continued, "Why do not you persuade him to go away?
The longer he stays, the worse it will be for him at last.

Pray advise him for his own sake, and for everybody's sake, to leave Bath directly.