She must have been gathering her resolution to say this, while she had been gone.

Perhaps she had been with her mother.

In that case he must be cautious....
"You mean--" "I mean just what I say.

We love one another, and I am willing to be his wife if he desires it--and with your permission.

But--" He waited for her to go on.
"Another 'But'!" he said presently, though with increasing mildness.
"I do not think he will desire it after a while.