The Duchess spoke quite slowly, so as to give herself time to enjoy the expression of the Prince.  It was delicious, on account of his profound astonishment, and that remnant of grand airs which the pose of his head and arms still betrayed.  The Prince had remained as if struck by a thunderbolt; from time to time, he exclaimed, in his high-pitched voice, shrill and perturbed, as though articulating with difficulty:  "How is this? how is this?" After concluding her compliment, the Duchess, as though from respect, afforded him ample time to reply; then she added:—­

“I venture to hope that your Most Serene Highness will deign to pardon the incongruity of my costume:”  but as she spoke, her mocking eyes flashed with so bright a gleam that the Prince could not meet them.  He looked at the ceiling, a sign with him of the most extreme embarrassment.

“How is this? how is this?” he said to himself again; then by good luck, he found a phrase:  “Madame la Duchesse, pray be seated,” and he himself pushed forward a chair, with fairly good grace.  The Duchess was by no means insensible to this attention, and she moderated the petulance of her glance.

“How is this? how is this?” still repeated the Prince inwardly, shifting so uneasily in his chair that one would have said that he could not find a secure position.

“I am going to take advantage of the freshness of the night to travel post,” resumed the Duchess, “and as my absence may be of some duration, I was unwilling to leave the territory of your Most Serene Highness without expressing my thanks for all the favors which for five years your Highness has deigned to show me.”  At these words the Prince at last understood; he turned pale.  It was as man of the world that he felt it most keenly, on finding himself mistaken in his predictions.  Then he assumed a grand air, in every way worthy of the portrait of Louis XIV., which was before his eyes.  “Admirable,” said the Duchess to herself, “there is a man.”

“And what is the motive of this sudden departure?” asked the Prince, in a fairly firm tone.

“I have contemplated leaving, for some time,” replied the Duchess, “and a slight insult which has been shown to Monsignor del Dongo, who is to be condemned to-morrow to death or to the galleys makes me hasten my departure.”

“And to what city are you going?”

“To Naples, I think.”  As she arose, she added, “It only remains for me to take leave of your Most Serene Highness, and to thank him very humbly for all his earlier kindnesses.”  She, on her part, spoke with so firm an air that the Prince saw clearly that in a few seconds all would be finished.  He knew that if a triumphant departure was once effected, all compromise would be impossible.  She was not the woman to retrace her steps.  He hastened after her.

“But you know very well, Madame la Duchesse,” he said, taking her hand, “that I have always regarded you with a friendship to which it needed only a word from you to give another name.  But a murder has been committed; there is no way of denying that.  I have intrusted the conduct of the case to my best judges ...”