Duvall\'s ride back to town with Mrs. Morton and Ruth was quite uneventful. The latter, as she had explained, was ill, weak, indisposed to talk. Duvall and Mrs. Morton kept up a brisk conversation upon topics of the day, but both knew that it was of the girl they were thinking, and their interest in the subjects they discussed was clearly forced. Both were glad when the car at last stopped before the apartment building, and the long ride was over.

Mrs. Morton invited Duvall to come in and dine with them, and he promptly accepted. Ruth seemed indifferent. Assisted by her maid, she left the car and on reaching the apartment, at once went to her room.

"You will excuse me, I know," she said to Duvall. "I am tired out, and think I had better lie down at once. Nora will bring me some dinner," she said, turning to her mother.

Duvall and Mrs. Morton ate their dinner in silence. Some sense of oppression, of impending evil, hung over them both. Mrs. Morton left the table toward the close of the meal, and went to her daughter\'s room. With the solicitude of the typical mother she arranged the windows. That opening to the fire escape she raised to its full height. The one facing upon the court she left as it was, raised some six or eight inches. Then, having kissed her daughter good night, she returned to the library, where Duvall sat smoking a cigar.

"Ruth has gone to bed," she told him. "Both the windows in her room are open, the one on the fire-escape wide, the other partly raised."

Duvall looked at her with an expression of doubt.

"I think it would be better, for the present," he said, "to close and fasten the one opening on the fire escape. We cannot tell to what danger your daughter may be exposed."

Mrs. Morton rose and left the room.

"I will do as you advise," she said. Going to Ruth\'s bedroom she closed and fastened the window in question, then she went back to the library.

"Have you hit upon any theory to account for the sending of these letters?" she asked.

Duvall shook his head. "The whole thing is very mysterious," he said. "Of course it was easy enough for anyone to leave the photograph at the studio this afternoon. In fact it might readily have been done by one of the other actresses, who might be jealous of your daughter\'s success. But if the thing was done by anyone employed at the studio, how can we account for the message left in the bedroom at half-past nine this morning, the one we found on the floor? If the woman who is responsible for these threats was at the studio this morning, how could she arrange to have the note left in your daughter\'s bedroom here at the same hour? That would seem to imply a confederate. I confess that the entire matter is for the moment beyond me."

"Were you able to find out anything concerning the telegram which came this morning?"

"Nothing, except that it was sent by a woman. I was not surprised to learn that. Naturally I should expect that a woman was responsible for these threats. But what woman? That is the question." He sat for a long time, thinking, his eyes fixed upon the floor.

Suddenly there came a ring at the doorbell. Mrs. Morton, without waiting for the maid, sprang to the hall, with Duvall close at her heels. As she threw it open, they saw a man standing in the doorway. Duvall was the first to recognize their caller.

"How do you do, Mr. Baker," he said, holding out his hand.

Mr. Baker came in, and greeted Mrs. Morton.

"I didn\'t expect to find Mr. Duvall here," he said. "In fact, I came to you to get his hotel address. Luckily I won\'t need it, now."

"Anything new?" Duvall asked, as they returned to the library.

"Nothing much. I got those samples of the writing of the various typewriters, as you requested," Baker replied, "and I thought that instead of waiting until to-morrow, it would be better to bring them to you to-night." He took a sheaf of papers from his pocket. "There are thirty-two in all. What are you going to do with them?" He placed the papers in Duvall\'s hand.

The latter sat down at the library table and placed the sheets of paper before him.

"Of course you know," he said to Baker, "that every typewriting machine has its unmistakable peculiarities. It is almost impossible to find a machine that has been used at all, that has not developed certain individual defects, or qualities, found in no other machine. Now let us take for instance the letters that Miss Morton has received during the past few days. They have all been written on the same machine, and I am of the opinion that it is a fairly old one. While going down to the studio this afternoon, I worked out and wrote down in my notebook the particular features which appear in all these letters." He took a small leather-covered book from his pocket.

"In the first place," he said, "the letter \'a\' throughout the several communications is always found to be out of line. The key bar is doubtless a trifle bent. Let us, therefore, see if, in any of the samples you have brought me, there exists a similar defect."

He took the samples of writing, one by one, and after scrutinizing them carefully, passed them over to Baker, who likewise subjected them to a critical examination. When their work was completed, it was found that of the thirty-two samples, the displacement of the letter "a" occurred in but three, and in one of these it was so slight as to be scarcely noticeable. Duvall laid the three pages to one side. "A second fault shown in the typewriting of the letters," he said, "is to be found in the capital \'W.\' Its lower right-hand corner has been worn or broken off, so that it invariably fails to register." He handed one of the letters to Baker. "See here, and here. The corner of the \'W\' instead of being clear and distinct, is blunt and defective. Let us see whether a similar fault is to be found in any one of these three samples." He picked up the three sheets of paper that he had placed to one side.

As he examined them, Mr. Baker and Mrs. Morton saw a shadow of disappointment cross his face. He handed the three pages to Baker.

"The threatening letters were not written on any machine at your studio," he said.

Baker took the pages and looked them over carefully.

"No," he said at length. "You are right. None of these show the second defect you have named."

"Well," observed Duvall cheerfully, "we have accomplished something, at least. We know that these letters were not written at the studio, and it seems reasonably certain that the woman we are looking for has a typewriter in her rooms, or wherever she may live. Of course she might have had the typewriting done by some public stenographer, but I consider it unlikely. A person sending threats of this character would not be apt to entrust so dangerous a secret to a third person. We must therefore make up our minds to find a woman who has a typewriting machine, and knows how to use it."

"There are probably a hundred thousand such women in New York," Baker observed, gloomily.

"No doubt. But we have more information than that about the person who sent these letters."

"What, for instance?" asked Baker and Mrs. Morton in a breath.

"Well, in the first place, this woman was able to secure possession of a photograph of Miss Morton." He took the hideously distorted picture from his pocket. "Do either of you know where this photograph was made?"

Mrs. Morton examined the picture with a shudder. Then she rose, went to a cabinet at the other end of the room, and took out an album. Returning to the table, she placed the book before her, and began to turn the pages. In a few moments she found what she was looking for, a duplicate of the likeness which lay before them, with the exception, of course, of its frightful distortions.

"This picture was made by Gibson, on Fifth Avenue," she said, referring to the photograph in the book. Both Baker and Duvall saw at once that on the retouched picture, the name of the photographer had been scratched off.

"How many of them were made, and what became of them?" Duvall asked quickly.

"Ordinarily I could not answer such a question," Mrs. Morton replied, "for Ruth has had many photographs taken, and we have not of course kept a record of them, or what has become of them, but in this particular case I happen to remember that she did not like the pose particularly, and ordered but half a dozen. I do not think that she gave any of them away. If I am right in my supposition, there should be five more here in the apartment." Closing the book, Mrs. Morton went to the cabinet again, and took out a portfolio containing numberless photographs of her daughter in all sorts of poses.

After some searching, she produced a brown-paper envelope, containing a number of pictures, all taken by the same photographer, at the same time. There were in the envelope four copies of the photograph, the fifth of which was contained in the album.

"Evidently one has been given away," Duvall exclaimed. "Now if we can only find out to whom, our search for the writer of these letters may be very quickly ended."

Mr. Baker regarded them both with a puzzled look.

"I have seen that picture before," he said, "and of course I could not have done so, had I not seen the one that is missing." He sat for a while in silence, searching his recollection for a solution of the problem. Suddenly he spoke. "There was a picture like that in my office, at one time," he exclaimed. "Miss Morton sent a number down, for advertising purposes, and I am positive that this one was among them. I remember distinctly the pose of the head, the unusual arrangement of the hair. That photograph should be in our files. The fact that it has been taken out shows that the person who has been writing these letters is a member of our own staff, or at least has access to our files."

"That does not necessarily follow," observed Duvall.

"Why not?"

"Because the picture might have been obtained from the photographer."

"But they are not allowed to dispose of the portraits of others, without the sitter\'s permission."

"I know that, but they sometimes do so, especially in the case of anyone so well known as Miss Morton. She has become a sort of public character.

"Well," remarked Duvall, "we can readily find out, in the morning. You, Mr. Baker, can go through your files, and should you find the photograph to be there, I will take the matter up with the photographer. If, on the contrary, the picture is missing, it will be fairly conclusive evidence that the person or persons we are looking for are in some way connected with the studio."

"I will make an investigation the first thing in the morning," Mr. Baker announced, rising. "Do you expect to be at the studio early, Mr. Duvall?"

"Yes. Quite early."

"Then we had best leave matters until then. Good night. Good night, Mrs. Morton." He turned and started toward the door.

He had proceeded but a few steps, when the three occupants of the room were startled by a series of sudden and agonizing cries. From the rear of the apartment came a succession of screams so piercing in their intensity, so filled with horror, that they found themselves for a moment unable to stir. Then Mrs. Morton gave a cry of anguish, and darted out into the hall, closely followed by Duvall and Mr. Baker.

The screams continued, filling the entire apartment with their clamor. That the voice which uttered them was that of Ruth Morton none of the three doubted for a moment. With sinking hearts they went on, prepared for the worst. Duvall found himself dreading the moment when they should reach the bedroom door, and face the girl, her beauty, perhaps, disfigured beyond all recognition.

There was a sharp turn, at the end of the hall, into a shorter cross hall, at the end of which was the door of Ruth\'s bedroom. It was closed, but as though in response to Mrs. Morton\'s agonized appeals, it suddenly opened as they reached it, and Ruth Morton, pale as death, appeared.

With wide open eyes staring straight ahead, she half stepped, half fell through the doorway, her slender figure clothed only in her night dress. "Ruth," Mrs. Morton screamed, as she caught sight of her daughter.

The girl tried to say something, but her tongue failed her. Then, with a faint moan, she lurched forward and fell limply into her mother\'s arms.