Corsini went to the Palace at once, much as he disliked entering the house of which the hateful and treacherous Prince was master. He could see that the young Princess was very agitated as she greeted him. "It is very kind of you to come so quickly, Signor. What I really wanted to see you about was this. In that letter you wrote me when you sent me that piece of music I asked for, you made use of certain expressions which I could not quite understand. You spoke of my having done you some service for which you wished to express your thanks." The Italian looked at her steadily and intently, but in that deep gaze there was a very tender expression. "Can you yourself recall no service that you have rendered me, Princess?" So he knew. Of course, if he had not guessed of his own volition, Beilski would have told him that she had sent that letter of warning. "Ah, I see you have found out," she faltered. "Well, on the spur of the moment I did my best, and I am glad that the result was so successful." "I shall ever remember it with the deepest feelings of gratitude," said the young musician fervently. "It could have been no light matter for you to act as you did, to run the risk of being detected." There was now no further need of fencing on either side. "Signor, since there is now such a frank understanding between us, I want to ask your advice on a matter that is troubling me very much." In tones of unmistakable sincerity he assured her that his services were whole-heartedly at her disposal. "My mother, alas! cannot help me. She is so seriously ill with diphtheria that we are forbidden to go to her room; only the doctor and the nurse are allowed there." Corsini expressed his deep regret at the Princess's severe indisposition. Nada resumed, in her soft, musical voice: "This morning my brother and I had a serious quarrel." A vivid blush spread over her charming face as she recalled how the quarrel had begun with his taunting her with her preference for the man whom he called "a strolling player." "We have had many quarrels in our time," she explained. "He is violent and overbearing, and breaks in the most ungovernable rages. At such times, I think, he goes actually mad for the moment. This particular quarrel, however, has left a deeper impression than most. He has threatened to lock me up in a gloomy old Castle in the Caucasus, as a punishment for my venturing to incur his displeasure." "And is there any valid, or sufficiently apparent, reason for his displeasure?" asked Corsini. "Or perhaps I am indiscreet in putting that question." "Oh, none at all," replied the Princess, with a return of that vivid blush; "mere trifles that a less violent man would smile at. He has used this threat once or twice before, but to-day he spoke as if he meant it." Corsini thought deeply before he answered. Had Zouroff actually discovered the part she had played in his rescue, and was this his revenge?