Arnold yielded.  They went into the library together.  Sir Patrick pointed to the writing-table.  “Relieve your mind there,” he said.  “And let me find you a reasonable man again when I come back.”

When he returned to the library the letter was written; and Arnold’s mind was so far relieved—­for the time at least.

“I shall take your letter to Blanche myself,” said Sir Patrick, “by the train that leaves for London in half an hour’s time.”

“You will let me go with you?”

“Not to-day.  I shall be back this evening to dinner.  You shall hear all that has happened; and you shall accompany me to London to-morrow—­if I find it necessary to make any lengthened stay there.  Between this and then, after the shock that you have suffered, you will do well to be quiet here.  Be satisfied with my assurance that Blanche shall have your letter.  I will force my authority on her step-mother to that extent (if her step-mother resists) without scruple.  The respect in which I hold the sex only lasts as long as the sex deserves it—­and does not extend to Lady Lundie.  There is no advantage that a man can take of a woman which I am not fully prepared to take of my sister-in-law.”

With that characteristic farewell, he shook hands with Arnold, and departed for the station.

At seven o’clock the dinner was on the table.  At seven o’clock Sir Patrick came down stairs to eat it, as perfectly dressed as usual, and as composed as if nothing had happened.

“She has got your letter,” he whispered, as he took Arnold’s arm, and led him into the dining-room.

“Did she say any thing?”

“Not a word.”

“How did she look?”

“As she ought to look—­sorry for what she has done.”

The dinner began.  As a matter of necessity, the subject of Sir Patrick’s expedition was dropped while the servants were in the room—­to be regularly taken up again by Arnold in the intervals between the courses.  He began when the soup was taken away.

“I confess I had hoped to see Blanche come back with you!” he said, sadly enough.

“In other words,” returned Sir Patrick, “you forgot the native obstinacy of the sex.  Blanche is beginning to feel that she has been wrong.  What is the necessary consequence?  She naturally persists in being wrong.  Let her alone, and leave your letter to have its effect.  The serious difficulties in our way don’t rest with Blanche.  Content yourself with knowing that.”

The fish came in, and Arnold was silenced—­until his next opportunity came with the next interval in the course of the dinner.

“What are the difficulties?” he asked