A few minutes afterward an unwonted bustle pervaded the dwelling and some one rapped at the door of Madame Bastien's chamber. "Who is there?" she asked. "I, Marguerite, madame." "What do you want?" "Doctor Dufour is here, madame. He just arrived on horseback." "Light a fire in the sitting-room and ask the doctor to wait for me there. I will be down in a moment." Then, recollecting that she would be obliged to leave her son, Madame Bastien recalled the servant, and said: "I have changed my mind. I will see the doctor here in my room. Show him up at once." Almost immediately the doctor appeared, preceded by Marguerite. "Good Heavens! what is the matter with you?" exclaimed M. Dufour on seeing Marie. "Nothing, doctor--" "Nothing!" repeated the physician, scrutinising Marie with evident surprise, so terrible was the change which the events of the previous evening had wrought in her appearance. "Nothing?" "Ah, yes, I know," replied Madame Bastien, with a heart-broken smile, reading the doctor's thoughts from the expression of his face. Then placing a finger on her lips, she added, in a low tone, with a meaning glance toward the door of Frederick's chamber: "We must be very careful, my dear doctor, my son is in there asleep. He has had a terrible experience this evening. I was about to write to you and ask you to come to-morrow. It was Heaven that sent you." "As my coming seems so opportune, I shall not have to apologise for coming at such an unseasonable hour. I wished to talk with you about a matter that would brook no delay, so I ventured to come almost in the middle of the night and at the risk of disturbing you." "My God! what is it?" "Your son is asleep, is he not?" "I think so." "But he might hear us if he is not, so let us go to the other end of the room and speak low, for it is a matter that concerns him." CHAPTER XVII. "I wish to speak to you in regard to the mental and physical change which you have noticed in your son, and which is giving you such grave uneasiness." "Grave indeed, doctor." "There is a possibility of curing him, I think." "You really think you can, my dear doctor." "I? No." "What do you mean?" "Have the goodness to read this, madame," said the doctor, drawing a letter from his pocket and handing it to Madame Bastien, who, greatly astonished, took it, and read as follows: "'MY DEAR PIERRE:--The diligence stops here for an hour and I take advantage of the opportunity thus afforded to write to you. "'After leaving you last evening the subject of our last conversation engrossed my thoughts to the exclusion of all other subjects, for what I had seen and heard could not fail to make a deep impression upon me.