For some days past Fraulein Rottenmeier had gone about rather silently and as if lost in thought. As twilight fell, and she passed from room to room, or along the long corridors, she was seen to look cautiously behind her, and into the dark corners, as if she thought some one was coming silently behind her and might unexpectedly give her dress a pull. Nor would she now go alone into some parts of the house. If she visited the upper floor where the grand guest-chambers were, or had to go down into the large mysterious council-chamber, where every footstep echoed, and the old senators with their big white collars looked down so solemnly and immovably from their frames, she regularly called Tinette to accompany her, in case, as she said, there might be something to carry up or down. Tinette on her side did exactly the same; if she had business upstairs or down, she called Sebastian to accompany her, and there was always something he must help her with which she could not carry alone. More curious still, Sebastian, also, if sent into one of the more distant rooms, always called John to go with him in case he should want his assistance in bringing what was required. And John readily obeyed, although there was never anything to carry, and either might well have gone alone; but he did not know how soon he might want to ask Sebastian to do the same service for him. And while these things were going on upstairs, the cook, who had been in the house for years, would stand shaking her head over her pots and kettles, and sighing, "That ever I should live to know such a thing."

For something very strange and mysterious was going on in Herr Sesemann's house. Every morning, when the servants went downstairs, they found the front door wide open, although nobody could be seen far or near to account for it. During the first few days that this happened every room and corner was searched in great alarm, to see if anything had been stolen, for the general idea was that a thief had been hiding in the house and had gone off in the night with the stolen goods; but not a thing in the house had been touched, everything was safe in its place. The door was doubly locked at night, and for further security the wooden bar was fastened across it; but it was no good--next morning the door again stood open. The servants in their fear and excitement got up extra early, but not so early but what the door had been opened before they got downstairs, although everything and everybody around were still wrapped in slumber, and the doors and windows of the adjoining houses all fast shut. At last, after a great deal of persuasion from Fraulein Rottenmeier, Sebastian and John plucked up courage and agreed to sit up one night in the room next to the large council-chamber and to watch and see what would happen. Fraulein Rottenmeier looked up several weapons belonging to the master, and gave these and a bottle of spirits to Sebastian, so that their courage might not faint if it came to a fight.

On the appointed night the two sat down and began at once to take some of the strengthening cordial, which at first made them very talkative and then very sleepy, so that they leant back in their seats and became silent. As midnight struck, Sebastian roused himself and called to his companion, who, however, was not easy to wake, and kept rolling his head first to one side and then the other and continuing to sleep. Sebastian began to listen more attentively, for he was wide awake now. Everything was still as a mouse, all sound had died away from the streets even. He did not feel inclined to go to sleep again, for the stillness was ghostly to him, and he was afraid now to raise his voice to rouse John, so he shook him gently to make him stir. At last, as one struck, John work up, and came back to the consciousness of why he was sitting in a chair instead of lying in his bed. He now got up with a great show of courage and said, "Come, Sebastian, we must go outside and see what is going on; you need not be afraid, just follow me."

Whereupon he opened the door wide and stepped into the hall. Just as he did so a sudden gust of air blew through the open front door and put out the light which John held in his hand. He started back, almost overturning Sebastian, whom he clutched and pulled back into the room, and then shutting the door quickly he turned the key as far as he could make it go. Then he pulled out his matches and lighted his candle again. Sebastian, in the suddenness of the affair, did not know exactly what had happened, for he had not seen the open door or felt the breeze behind John's broad figure. But now, as he saw the latter in the light, he gave a cry of alarm, for John was trembling all over and as white as a ghost. "What's the matter? What did you see, outside?" asked Sebastian sympathetically.

"The door partly open," gasped John, "and a white figure standing at the top of the steps--there it stood, and then all in a minute it disappeared."

Sebastian felt his blood run cold. The two sat down close to one another and did not dare move again till the morning broke and the streets began to be alive again. Then they left the room together, shut the front door, and went upstairs to tell Fraulein Rottenmeier of their experience. She was quite ready to receive them, for she had not been able to sleep at all in the anxiety of waiting to hear their report. They had no sooner given her details of the night's experience than she sat down and wrote straight off to Herr Sesemann, who had never received such a letter before in his life. She could hardly write, she told him, for her fingers were stiff with fear, and Herr Sesemann must please arrange to come back at once, for dreadful and unaccountable things were taking place at home. Then she entered into particulars of all that had happened, of how the door was found standing open every morning, and how nobody in the house now felt sure of their life in this unprotected state of things, and how it was impossible to tell what terrible results might follow on these mysterious doings.

Herr Sesemann answered that it was quite impossible for him to arrange to leave his business and return home at once. He was very much astonished at this ghost tale, but hoped by this time the ghost had disappeared. If, however, it still continued to disturb the household, would Fraulein Rottenmeier write to the grandmother and ask her if she could come and do something; she, he was sure, would soon find out a way to deal with the ghost so that it would not venture again to haunt his house. Fraulein Rottenmeier was not pleased with the tone of this letter; she did not think the matter was treated seriously enough. She wrote off without delay to Frau Sesemann, but got no more satisfactory reply from that quarter, and some remarks in the letter she considered were quite offensive. Frau Sesemann wrote that she did not feel inclined to take the journey again from Holstein to Frankfurt because Rottenmeier fancied she saw ghosts. There had never been a ghost in the house since she had known it, and if there was one now it must be a live one, with which Rottenmeier ought to be able to deal; if not she had better send for the watchman to help her.

Fraulein Rottenmeier, however, was determined not to pass any more days in a state of fear, and she knew the right course to pursue. She had as yet said nothing to the children of the ghostly apparitions, for she knew if she did that the children would not remain alone for a single moment, and that might entail discomfort for herself. But now she walked straight off into the study, and there in a low mysterious voice told the two children everything that had taken place. Clara immediately screamed out that she could not remain another minute alone, her father must come home, and Fraulein Rottenmeier must sleep in her room at night, and Heidi too must not be left by herself, for the ghost might do something to her. She insisted that they should all sleep together in one room and keep a light burning all night, and Tinette had better be in the next room, and Sebastian and John come upstairs and spend the night in the hall, so that they might call out and frighten the ghost the instant they saw it appear on the steps. Clara, in short, grew very excited, and Fraulein Rottenmeier had great difficulty in quieting her. She promised to write at once to her father, and to have her bed put in her room and not to be left alone for a moment. They could not all sleep in the same room, but if Heidi was frightened, why Tinette must go into her room. But Heidi was far more frightened of Tinette than of ghosts, of which the child had never before heard, so she assured the others she did not mind the ghost, and would rather be alone at night.

Fraulein Rottenmeier now sat down to write another letter to Herr Sesemann, stating that these unaccountable things that were going on in the house had so affected his daughter's delicate constitution that the worst consequences might be expected. Epileptic fits and St. Vitus's dance often came on suddenly in cases like this, and Clara was liable to be attacked by either if the cause of the general alarm was not removed.

The letter was successful, and two days later Herr Sesemann stood at his front door and rang the bell in such a manner that everybody came rushing from all parts of the house and stood looking affrighted at everybody else, convinced that the ghost was impudently beginning its evil tricks in daylight. Sebastian peeped cautiously through a half-closed shutter; as he did so there came another violent ring at the bell, which it was impossible to mistake for anything but a very hard pull from a non-ghostly hand. And Sebastian recognised whose hand it was, and rushing pell-mell out of the room, fell heels over head downstairs, but picked himself up at the bottom and flung open the street door. Herr Sesemann greeted him abruptly and went up without a moment's delay into his daughter's room. Clara greeted him with a cry of joy, and seeing her so lively and apparently as well as ever, his face cleared, and the frown of anxiety passed gradually away from it as he heard from his daughter's own lips that she had nothing the matter with her, and moreover was so delighted to see him that she was quite glad about the ghost, as it was the cause of bringing him home again.

"And how is the ghost getting on?" he asked, turning to Fraulein Rottenmeier, with a twinkle of amusement in his eye.

"It is no joke, I assure you," replied that lady. "You will not laugh yourself to-morrow morning, Herr Sesemann; what is going on in the house points to some terrible thing that has taken place in the past and been concealed."

"Well, I know nothing about that," said the master of the house, "but I must beg you not to bring suspicion on my worthy ancestors. And now will you kindly call Sebastian into the dining- room, as I wish to speak to him alone."

Herr Sesemann had been quite aware that Sebastian and Fraulein Rottenmeier were not on the best of terms, and he had his ideas about this scare.

"Come here, lad," he said as Sebastian appeared, "and tell me frankly--have you been playing at ghosts to amuse yourself at Fraulein Rottenmeier's expense?"

"No, on my honor, sir; pray, do not think it; I am very uncomfortable about the matter myself," answered Sebastian with unmistakable truthfulness.

"Well, if that is so, I will show you and John to-morrow morning how ghosts look in the daylight. You ought to be ashamed of yourself, Sebastian, a great strong lad like you, to run away from a ghost! But now go and take a message to my old friend the doctor; give him my kind regards, and ask him if he will come to me to-night at nine o'clock without fail; I have come by express from Paris to consult him. I shall want him to spend the night here, so bad a case is it; so he will arrange accordingly. You understand?"

"Yes, sir," replied Sebastian, "I will see to the matter as you wish." Then Herr Sesemann returned to Clara, and begged her to have no more fear, as he would soon find out all about the ghost and put an end to it.

Punctually at nine o'clock, after the children had gone to bed and Fraulein Rottenmeier had retired, the doctor arrived. He was a grey-haired man with a fresh face, and two bright, kindly eyes. He looked anxious as he walked in, but, on catching sight of his patient, burst out laughing and clapped him on the shoulder. "Well," he said, "you look pretty bad for a person that I am to sit up with all night."

"Patience, friend," answered Herr Sesemann, "the one you have to sit up for will look a good deal worse when we have once caught him."

"So there is a sick person in the house, and one that has first to be caught?"

"Much worse than that, doctor! a ghost in the house! My house is haunted!"

The doctor laughed aloud.

"That's a nice way of showing sympathy, doctor!" continued Herr, Sesemann. "It's a pity my friend Rottenmeier cannot hear you. She is firmly convinced that some old member of the family is wandering about the house doing penance for some awful crime he committed."

"How did she become acquainted with him?" asked the doctor, still very much amused.

So Herr Sesemann recounted to him how the front door was nightly opened by somebody, according to the testimony of the combined household, and he had therefore provided two loaded revolvers, so as to be prepared for anything that happened; for either the whole thing was a joke got up by some friend of the servants, just to alarm the household while he was away--and in that case a pistol fired into the air would procure him a wholesome fright-- or else it was a thief, who, by leading everybody at first to think there was a ghost, made it safe for himself when he came later to steal, as no one would venture to run out if they heard him, and in that case too a good weapon would not be amiss.

The two took up their quarters for the night in the same room in which Sebastian and John had kept watch. A bottle of wine was placed on the table, for a little refreshment would be welcome from time to time if the night was to be passed sitting up. Beside it lay the two revolvers, and two good-sized candles had also been lighted, for Herr Sesemann was determined not to wait for ghosts in any half light.

The door was shut close to prevent the light being seen in the hall outside, which might frighten away the ghost. And now the two gentlemen sat comfortably back in the arm-chairs and began talking of all sorts of things, now and then pausing to take a good draught of wine, and so twelve o'clock struck before they were aware.

"The ghost has got scent of us and is keeping away to-night," said the doctor.

"Wait a bit, it does not generally appear before one o'clock," answered his friend.

They started talking again. One o'clock struck. There was not a sound about the house, nor in the street outside. Suddenly the doctor lifted his finger.

"Hush! Sesemann, don't you hear something?"

They both listened, and they distinctly heard the bar softly pushed aside and then the key turned in the lock and the door opened. Herr Sesemann put out his hand for his revolver.

"You are not afraid, are you?" said the doctor as he stood up.

"It is better to take precautions," whispered Herr Sesemann, and seizing one of the lights in his other hand, he followed the doctor, who, armed in like manner with a light and a revolver, went softly on in front. They stepped into the hall. The moonlight was shining in through the open door and fell on a white figure standing motionless in the doorway.

"Who is there?" thundered the doctor in a voice that echoed through the hall, as the two men advanced with lights and weapons towards the figure.

It turned and gave a low cry. There in her little white nightgown stood Heidi, with bare feet, staring with wild eyes at the lights and the revolvers, and trembling from head to foot like a leaf in the wind. The two men looked as one another in surprise.

"Why, I believe it is your little water-carrier, Sesemann," said the doctor.

"Child, what does this mean?" said Herr Sesemann. "What did you want? why did you come down here?"

White with terror, and hardly able to make her voice heard, Heidi answered, "I don't know."

But now the doctor stepped forward. "This is a matter for me to see to, Sesemann; go back to your chair. I must take the child upstairs to her bed."

And with that he put down his revolver and gently taking the child by the hand led her upstairs. "Don't be frightened," he said as they went up side by side, "it's nothing to be frightened about; it's all right, only just go quietly."

On reaching Heidi's room the doctor put the candle down on the table, and taking Heidi up in his arms laid her on the bed and carefully covered her over. Then he sat down beside her and waited until Heidi had grown quieter and no longer trembled so violently. He took her hand and said in a kind, soothing voice, "There, now you feel better, and now tell me where you were wanting to go to?"

"I did not want to go anywhere," said Heidi. "I did not know I went downstairs, but all at once I was there."

"I see, and had you been dreaming, so that you seemed to see and hear something very distinctly?"

"Yes, I dream every night, and always about the same things. I think I am back with the grandfather and I hear the sound in the fir trees outside, and I see the stars shining so brightly, and then I open the door quickly and run out, and it is all so beautiful! But when I wake I am still in Frankfurt." And Heidi struggled as she spoke to keep back the sobs which seemed to choke her.

"And have you no pain anywhere? no pain in your head or back?"

"No, only a feeling as if there were a great stone weighing on me here."

"As if you had eaten something that would not go down."

"No, not like that; something heavy as if I wanted to cry very much."

"I see, and then do you have a good cry?"

"Oh, no, I mustn't; Fraulein Rottenmeier forbade me to cry."

"So you swallow it all down, I suppose? Are you happy here in Frankfurt?"

"Yes," was the low answer; but it sounded more like "No."

"And where did you live with your grandfather?"

"Up on the mountain."

"That wasn't very amusing; rather dull at times, eh?"

"No, no, it was beautiful, beautiful!" Heidi could go no further; the remembrance of the past, the excitement she had just gone through, the long suppressed weeping, were too much for the child's strength; the tears began to fall fast, and she broke into violent weeping.

The doctor stood up and laid her head kindly down on the pillow. "There, there, go on crying, it will do you good, and then go to sleep; it will be all right tomorrow."

Then he left the room and went downstairs to Herr Sesemann; when he was once more sitting in the armchair opposite his friend, "Sesemann," he said, "let me first tell you that your little charge is a sleep-walker; she is the ghost who has nightly opened the front door and put your household into this fever of alarm. Secondly, the child is consumed with homesickness, to such an extent that she is nearly a skeleton already, and soon will be quite one; something must be done at once. For the first trouble, due to her over-excited nerves, there is but one remedy, to send her back to her native mountain air; and for the second trouble there is also but one cure, and that the same. So to- morrow the child must start for home; there you have my prescription."

Herr Sesemann had arisen and now paced up and down the room in the greatest state of concern.

"What!" he exclaimed, "the child a sleep-walker and ill! Home- sick, and grown emaciated in my house! All this has taken place in my house and no one seen or known anything about it! And you mean, doctor, that the child who came here happy and healthy, I am to send back to her grandfather a miserable little skeleton? I can't do it; you cannot dream of my doing such a thing! Take the child in hand, do with her what you will, and make her whole and sound, and then she shall go home; but you must do something first."

"Sesemann," replied the doctor, "consider what you are doing! This illness of the child's is not one to be cured with pills and powders. The child has not a tough constitution, but if you send her back at once she may recover in the mountain air, if not - -you would rather she went back ill than not at all?"

Herr Sesemann stood still; the doctor's words were a shock to him.

"If you put it so, doctor, there is assuredly only one way--and the thing must be seen to at once." And then he and the doctor walked up and down for a while arranging what to do, after which the doctor said good-bye, for some time had passed since they first sat down together, and as the master himself opened the hall door this time the morning light shone down through it into the house.