For the third time Professor Augustus S. F. X. Van Dusen — so-called The Thinking Machine — read the letter. It was spread out in front of him on the table, and his blue eyes were narrowed to mere slits as he studied it through his heavy eyeglasses. The young woman who had placed the letter in his hands, Miss Elizabeth Devan, sat waiting patiently on the sofa in the little reception room of The Thinking Machine’s house. Her blue eyes were opened wide and she stared as if fascinated at this man who had become so potent a factor in the solution of intangible mysteries.

Here is the letter:

To those Concerned:

Tired of it all I seek the end, and am content. Ambition now is dead; the grave yawns greedily at my feet, and with the labor of my own hands lost I greet death of my own will, by my own act. To my son I leave all, and you who maligned me, you who discouraged me, you may read this and know I punish you thus. It’s for him, my son, to forgive. I dared in life and dare dead your everlasting anger, not alone that you didn’t speak but that you cherished secret, and my ears are locked forever against you. My vault is my resting place. On the brightest and dearest page of life I wrote (7) my love for him. Family ties, binding as the Bible itself, bade me give all to my son.

Good-bye. I die.

Pomeroy Stockton

“Under just what circumstances did this letter come into your possession, Miss Devan?” The Thinking Machine asked. “Tell me the full story; omit nothing.”

The scientist sank back into his chair with his enormous yellow head pillowed comfortably against the cushion and his long, steady fingers pressed tip to tip. He didn’t even look at his pretty visitor. She had come to ask for information; he was willing to give it, because it offered another of those abstract problems which he always found interesting. In his own field — the sciences — his fame was worldwide. This concentration of a brain which had achieved so much on more material things was perhaps a sort of relaxation.

Miss Devan had a soft, soothing voice, and as she talked it was broken at times by what seemed to be a sob. Her face was flushed a little, and she emphasized her points by a quick clasping and unclasping of her daintily gloved hands.

“My father, or rather my adopted father, Pomeroy Stockton, was an inventor,” she began. “We lived in a great, old-fashioned house in Dorchester. We have lived there since I was a child. When I was only five or six years old, I was left an orphan and was adopted by Mr. Stockton, then a man of forty years. I am now twenty-three. I was raised and cared for by Mr. Stockton, who always treated me as a daughter. His death, therefore, was a great blow to me.

“Mr. Stockton was a widower with only one child of his own, a son, John Stockton, who is now about thirty one years old. He is a man of irreproachable character, and has always, since I first knew him, been religiously inclined. He is the junior partner in a great commercial company, Dutton & Stockton, leather men. I suppose he has an immense fortune, for he gives largely to charity, and is, too, the active head of a large Sunday school.

“Pomeroy Stockton, my adopted father, almost idolized this son, although there was in his manner toward him something akin to fear. Close work had made my father querulous and irritable. Yet I don’t believe a better hearted man ever lived. He worked most of the time in a little shop, which he had installed in a large back room on the ground floor of the house. He always worked with the door locked. There were furnaces, moulds, and many things that I didn’t know the use of.”

“I know who he was,” said The Thinking Machine. “He was working to rediscover the secret of hardened copper — a secret which was lost in Egypt. I knew Mr. Stockton very well by reputation. Go on.”

“Whatever it was he worked on,” Miss Devan resumed, “he guarded it very carefully. He would permit no one at all to enter the room. I have never seen more than a glimpse of what was in it. His son particularly I have seen barred out of the shop a dozen times and every time there was a quarrel to follow.

“Those were the conditions at the time Mr. Stockton first became ill, six or seven months ago. At that time he double locked the doors of his shop, retired to his rooms on the second floor, and remained there in practical seclusion for two weeks or more. These rooms adjoined mine, and twice during that time I heard the son and the father talking loudly, as if quarreling. At the end of the two weeks, Mr. Stockton returned to work in the shop and shortly afterward the son, who had also lived in the house, took apartments in Beacon Street and removed his belongings from the house.

“From that time up to last Monday — this is Thursday — I never saw the son in the house. On Monday the father was at work as usual in the shop. He had previously told me that the work he was engaged in was practically ended and he expected a great fortune to result from it. About 5 o’clock in the afternoon on Monday the son came to the house. No one knows when he went out. It is a fact, however, that Father did not have dinner at the usual time, 6:30. I presumed he was at work, and did not take time for his dinner. I have known him to do this many times.”

For a moment the girl was silent and seemed to be struggling with some deep grief which she could not control.

“And next morning?” asked The Thinking Machine gently.

“Next morning,” the girl went on, “Father was found dead in the workshop. There were no marks on his body, nothing to indicate at first the manner of death. It was as if he had sat in his chair beside one of the furnaces and had taken poison and died at once. A small bottle of what I presume to be prussic acid was smashed on the floor, almost beside his chair. We discovered him dead after we had rapped on the door several times and got no answer. Then Montgomery, our butler, smashed in the door, at my request. There we found Father.

“I immediately telephoned to the son, John Stockton, and he came to the house. The letter you now have was found in my father’s pocket. It was just as you see it. Mr. Stockton seemed greatly agitated and started to destroy the letter. I induced him to give it to me, because instantly it occurred to me that there was something wrong about all of it. My father had talked too often to me about the future, what he intended to do and his plans for me. There may not be anything wrong. The letter may be just what it purports to be. I hope it is — oh — I hope it is. Yet everything considered —”

“Was there an autopsy?” asked The Thinking Machine.

“No. John Stockton’s actions seemed to be directed against any investigation. He told me he thought he could do certain things which would prevent the matter coming to the attention of the police. My father was buried on a death certificate issued by a Dr. Benton, who has been a friend of John Stockton since their college days. In that way the appearance of suicide or anything else was covered up completely.

“Both before and after the funeral John Stockton made me promise to keep this letter hidden or else destroy it. In order to put an end to this I told him I had destroyed the letter. This attitude on his part, the more I thought of it, seemed to confirm my original idea that it had not been suicide. Night after night I thought of this, and finally decided to come to you rather than to the police. I feel that there is some dark mystery behind it all. If you can help me now —”

“Yes, yes,” broke in The Thinking Machine. “Where was the key to the workshop? In Pomeroy’s pocket? In his room? In the door?”

“Really, I don’t know,” said Miss Devan. “It hadn’t occurred to me.”

“Did Mr. Stockton leave a will?”

“Yes, it is with his lawyer, a Mr. Sloane.”

“Has it been read? Do you know what is in it?”

“It is to be read in a day or so. Judging from the second paragraph of the letter, I presume he left everything to his son.”

For the fourth time The Thinking Machine read the letter. At its end he again looked up at Miss Devan.

“Just what is your interpretation of this letter from one end to the other?” he asked.

“Speaking from my knowledge of Mr. Stockton and the circumstances surrounding him,” the girl explained, “I should say the letter means just what it says. I should imagine from the first paragraph that something he invented had been taken away from him, stolen perhaps. The second paragraph and the third, I should say, were intended as a rebuke to certain relatives — a brother and two distant cousins — who had always regarded him as a crank and took frequent occasion to tell him so. I don’t know a great deal of the history of that other branch of the family. The last two paragraphs explain themselves except —”

“Except the figure seven,” interrupted the scientist. “Do you have any idea whatever as to the meaning of that?”

The girl took the letter and studied it closely for a moment.

“Not the slightest,” she said. “It does not seem to be connected with anything else in the letter.”

“Do you think it possible, Miss Devan, that this letter was written under coercion?”

“I do,” said the girl quickly, and her face flamed. “That’s just what I do think. From the first I have imagined some ghastly, horrible mystery back of it all.”

“Or, perhaps Pomeroy Stockton never saw this letter at all,” mused The Thinking Machine. “It may be a forgery?”

“Forgery!” gasped the girl. “Then John Stockton —”

“Whatever it is, forged or genuine,” The Thinking Machine went on quietly, “it is a most extraordinary document. It might have been written by a poet. It states things in such a roundabout way. It is not directly to the point, as a practical man would have written.”

There was silence for several minutes and the girl sat leaning forward on the table, staring into the inscrutable eyes of the scientist.

“Perhaps, perhaps,” she said, “there is a cipher of some sort in it?”

“That is precisely correct,” said The Thinking Machine emphatically. “There is a cipher in it, and a very ingenious one.”
2

It was twenty-four hours later that The Thinking Machine sent for Hutchinson Hatch, reporter, and talked over the matter with him. He had always found Hatch a discreet, resourceful individual, who was willing to aid in any way in his power.

Hatch read the letter, which The Thinking Machine had said contained a cipher, and then the circumstances as related by Miss Devan were retold to the reporter.

“Do you think it is a cipher?” asked Hatch in conclusion.

“It is a cipher,” replied The Thinking Machine. “If what Miss Devan has said is correct, John Stockton cannot have said anything about the affair. I want you to go and talk to him, find out all about him and what division of the property is made by the will. Does this will give everything to the son?

“Also find out what personal enmity there is between John Stockton and Miss Devan, and what was the cause of it. Was there a man in it? If so, who? When you have done all this, go to the house in Dorchester and bring me the family Bible, if there is one there. It’s probably a big book. If it is not there, let me know immediately by ‘phone. Miss Devan will, I suppose, give it to you, if she has it.”

With these instructions Hatch went away. Half an hour later he was in the private office of John Stockton at the latter’s place of business. Mr. Stockton was a man of long visage, rather angular and clerical in appearance. There was a smug satisfaction about the man that Hatch didn’t quite approve of, and yet it was a trait which found expression only in a soft voice and small acts of needless courtesy.

A deprecatory look passed over Stockton’s face when Hatch asked the first question, which bore on his relationship with Pomeroy Stockton.

“I had hoped that this matter would not come to the attention of the press,” said Stockton in an oily, gentle tone. “It is something which can only bring disgrace upon my poor father’s memory, and his has been a name associated with distinct achievements in the progress of the world. However, if necessary, I will state my knowledge of the affair, and invite the investigation which, frankly, I will say, I tried to stop.”

“How much was your father’s estate?” asked Hatch.

“Something more than a million,” was the reply. “He made most of it through a device for coupling cars. This is now in use on practically all the railroads.”

“And the division of this property by will?” asked Hatch.

“I haven’t seen the will, but I understand that he left practically everything to me, settling an annuity and the home in Dorchester on Miss Devan, whom he had always regarded as a daughter.”

“That would give you then, say, two-thirds or three-quarters of the estate.”

“Something like that, possibly $800,000.”

“Where is this will now?”

“I understand in the hands of my father’s attorney, Mr. Sloane.”

“When is it to be read?”

“It was to have been read today, but there has been some delay about it. The attorney postponed it for a few days.”

“What, Mr. Stockton, was the purpose in making it appear that your father died naturally, when obviously he committed suicide and there is even a suggestion of something else?” demanded Hatch.

John Stockton sat up straight in his chair with a startled expression in his eyes. He had been rubbing his hands together complacently; now he stopped and stared at the reporter.

“Something else?” he asked. “Pray what else?”

Hatch shrugged his shoulders, but in his eyes there lay almost an accusation.

“Did any motive ever appear for your father’s suicide?”

“I know of none,” Stockton replied. “Yet, admitting that this is suicide, without a motive, it seems that the only fault I have committed is that I had a friend report it otherwise and avoided a police inquiry.”

“It’s just that. Why did you do it?”

“Naturally to save the family name from disgrace. But this something else you spoke of? Do you mean that anyone else thinks that anything other than suicide or natural death is possible?”

As he asked the question there came some subtle change over his face. He leaned forward toward the reporter. All trace of the sanctimonious smirk about the thin-lipped mouth had gone now.

“Miss Devan has produced the letter found on your father at death and has said —” began the reporter.

“Elizabeth! Miss Devan!” exclaimed John Stockton. He arose suddenly, paced several times across the room, then stopped in front of the reporter. “She gave me her word of honor that she would not make the existence of that letter known.”

“But she has made it public,” said Hatch. “And further she intimates that your father’s death was not even what it appeared to be, suicide.”

“She’s crazy, man, crazy,” said Stockton in deep agitation. “Who could have killed my father? What motive could there have been?”

There was a grim twitching of Hatch’s lips.

“Was Miss Devan legally adopted by your father?” he asked, irrelevantly.

“Yes.”

“In that event, disregarding other relatives, doesn’t it seem strange even to you that he gives three quarters of the estate to you — you have a fortune already — and only a small part to Miss Devan, who has nothing?”

“That’s my father’s business.”

There was a pause. Stockton was still pacing back and forth.

Finally he sank down in his chair at the desk, and sat for a moment looking at the reporter.

“Is that all?” he asked.

“I should like to know, if you don’t mind telling me, what direct cause there is for ill feeling between Miss Devan and you?”

“There is no ill feeling. We merely never got along well together. My father and I have had several arguments about her for reasons which it is not necessary to go into.”

“Did you have such an argument on the night before your father was found dead?”

“I believe there was something said about her.”

“What time did you leave the shop that night?”

“About 10 o’clock.”

“And you had been in the room with your father since afternoon, had you not?”

“Yes.”

“No dinner?”

“No.”

“How did you come to neglect that?”

“My father was explaining a recent invention he had perfected, which I was to put on the market.”

“I suppose the possibility of suicide or his death in any way had not occurred to you?”

“No, not at all. We were making elaborate plans for the future.”

Possibly it was some prejudice against the man’s appearance which made Hatch so dissatisfied with the result of the interview. He felt that he had gained nothing, yet Stockton had been absolutely frank, as it seemed. There was one last question.

“Have you any recollection of a large family Bible in your father’s house?” he asked.

“I have seen it several times,” Stockton said.

“Is it still there?”

“So far as I know, yes.”

That was the end of the interview, and Hatch went straight to the house in Dorchester to see Miss Devan. There, in accordance with instructions from The Thinking Machine, he asked for the family Bible.

“There was one here the other day,” said Miss Devan, “but it has disappeared.”

“Since your father’s death?” asked Hatch.

“Yes, the next day.”

“Have you any idea who took it?”

“Not unless — unless —”

“John Stockton! Why did he take it?” blurted Hatch.

There was a little resigned movement of the girl’s hands, a movement which said, “I don’t know.”

“He told me, too,” said Hatch indignantly, “that he thought the Bible was still here.”

The girl drew close to the reporter and laid one white hand on his sleeve. She looked up into his eyes and tears stood in her own. Her lips trembled.

“John Stockton has that book,” she said. “He took it away from here the day after my father died, and he did it for a purpose. What, I don’t know.”

“Are you absolutely positive he has it?” asked Hatch

“I saw it in his room, where he had hidden it,” replied the girl.
3

Hatch laid the results of the interviews before the scientist at the Beacon Hill home. The Thinking Machine listened without comment up to that point where Miss Devan had said she knew the family Bible to be in the son’s possession.

“If Miss Devan and Stockton do not get along well together, why should she visit Stockton’s place at all?” demanded The Thinking Machine.

“I don’t know,” Hatch replied, “except that she thinks he must have had some connection with her father’s death, and is investigating on her own account. What has this Bible to do with it anyway?”

“It may have a great deal to do with it,” said The Thinking Machine enigmatically. “Now, the thing to do is to find out if the girl told the truth and if the Bible is in Stockton’s apartment. Now, Mr. Hatch, I leave that to you. I would like to see that Bible. If you can bring it to me, well and good. If you can’t bring it, look at and study the seventh page for any pencil marks in the text, anything whatever. It might be even advisable, if you have the opportunity, to tear out that page and bring it to me. No harm will be done, and it can be returned in proper time.”

Perplexed wrinkles were gathering on Hatch’s forehead as he listened. What had page 7 of a Bible to do with what seemed to be a murder mystery? Who had said anything about a Bible, anyway? The letter left by Stockton mentioned a Bible, but that didn’t seem to mean anything. Then Hatch remembered that same letter carried a figure seven in parentheses which had apparently nothing to do and no connection with any other part of the letter. Hatch’s introspective study of the affair was interrupted by The Thinking Machine.

“I shall await your report here, Mr. Hatch. If it is what I expect, we shall go out late tonight on a little voyage of discovery. Meanwhile see that Bible and tell me what you find.”

Hatch found the apartments of John Stockton on Beacon Street without any difficulty. In a manner best known to himself he entered and searched the place. When he came out there was a look of chagrin on his face as he hurried to the house of The Thinking Machine nearby.

“Well?” asked the scientist.

“I saw the Bible,” said Hatch.

“And page 7?”

“Was torn out, missing, gone,” replied the reporter.

“Ah,” exclaimed the scientist. “I thought so. Tonight we will make the little trip I spoke of. By the way, did you happen to notice if John Stockton had or used a fountain pen?”

“I didn’t see one,” said Hatch.

“Well, please see for me if any of his employees have ever noticed one. Then meet me here tonight at 10 o’clock.”

Thus Hatch was dismissed. A little later he called casually on Stockton again. There, by inquiries, he established to his own satisfaction that Stockton did not own a fountain pen. Then with Stockton himself he took up the matter of the Bible again.

“I understand you to say, Mr. Stockton,” he began in his smoothest tone, “that you knew of the existence of a family Bible, but you did not know if it was still at the Dorchester place.”

“That’s correct,” said Stockton.

“How is it then,” Hatch resumed, “that that identical Bible is now at your apartments, carefully hidden in a box under a sofa?”

Mr. Stockton seemed to be amazed. He arose suddenly and leaned over toward the reporter with hands clenched. There was a glitter of what might have been anger in his eyes.

“What do you know about this? What are you talking about?” he demanded.

“I mean that you had said you did not know where this book was, and meanwhile have it hidden. Why?”

“Have you seen the Bible in my rooms?” asked Stockton.

“I have,” said the reporter coolly.

Now a new determination came into the face of the merchant. The oiliness of his manner was gone, the sanctimonious smirk had been obliterated, the thin lips closed into a straight, rigid line.

“I shall have nothing further to say,” he declared almost fiercely.

“Will you tell me why you tore out the seventh page of the Bible?” asked Hatch.

Stockton stared at him dully, as if dazed for a moment. All the color left his face. There came a startling pallor instead. When next he spoke, his voice was tense and strained.

“Is — is — the seventh page missing?”

“Yes,” Hatch replied. “Where is it?”

“I’ll have nothing further to say under any circumstances. That’s all.”

With not the slightest idea of what it might mean or what bearing it had on the matter, Hatch had brought out statements which were wholly at variance with facts. Why was Stockton so affected by the statement that page seven was gone? Why had the Bible been taken from the Dorchester home? Why had it been so carefully hidden? How did Miss Devan know it was there?

These were only a few of the questions that were racing through the reporter’s mind. He did not seem to be able to grasp anything tangible. If there were a cipher hidden in the letter, what was it? What bearing did it have on the case?

Seeking a possible answer to some of these questions, Hatch took a cab and was soon back at the Dorchester house. He was somewhat surprised to see The Thinking Machine standing on the stoop waiting to be admitted. The scientist took his presence as a matter of course.

“What did you find out about Stockton’s fountain pen?” he asked.

“I satisfied myself that he had not owned a fountain pen, at least recently enough for the pen to have been used in writing that letter. I presume that’s what inquiries in that direction mean.”

The two men were admitted to the house and after a few minutes Miss Devan entered. She understood when The Thinking Machine explained that they merely wished to see the shop in which Mr. Stockton had been found dead.

“And also if you have a sample of Mr. Stockton’s handwriting,” asked the scientist.

“It’s rather peculiar,” Miss Devan explained, “but I doubt if there is an authentic sample in existence large enough, that is, to be compared with that letter. He had a certain amount of correspondence, but this I did for him on the typewriter. Occasionally he would prepare an article for a scientific paper, but these were also dictated to me. He has been in the habit of doing so for years.”

“This letter seems to be all there is?”

“Of course his signature appears to checks and in other places. I can produce some of those for you. I don’t think, however, that there is the slightest doubt that he wrote this letter. It is his handwriting.”

“I suppose he never used a fountain pen?” asked The Thinking Machine.

“Not that I know of,” the girl replied. “I have one,” and she took it out of a little gold fascinator she wore at her bosom.

The scientist pressed the point of the pen against his thumb nail, and a tiny drop of blue ink appeared. The letter was written in black. The Thinking Machine seemed satisfied.

“And now the shop,” he suggested.

Miss Devan led the way through the long wide hall to the back of the building. There she opened a door, which showed signs of having been battered in, and admitted them. Then, at the request of The Thinking Machine, she rehearsed the story in full, showed him where Stockton had been found, where the prussic acid had been broken, and how the servant, Montgomery, had broken in the door at her request.

“Did you ever find the key to the door?”

“No. I can’t imagine what became of it.”

“Is this room precisely as it was when the body was found? That is, has anything been removed from it?”

“Nothing,” replied the girl.

“Have the servants taken anything out? Did they have access to this room?”

“They have not been permitted to enter it at all. The body was removed and the fragments of the acid bottle were taken away, but nothing else.”

“Have you ever known of pen and ink being in this room?”

“I hadn’t thought of it.”

“You haven’t taken them out since the body was found, have you?”

“I— I— er — have not,” the girl stammered.

Miss Devan left the room, and for an hour Hatch and The Thinking Machine conducted the search.

“Find a pen and ink,” The Thinking Machine instructed.

They were not found.

At midnight, which was six hours later, The Thinking Machine and Hutchinson Hatch were groping through the cellar of the Dorchester house by the light of a small electric lamp which shot a straight beam aggressively through the murky, damp air. Finally the ray fell on a tiny door set in the solid wall of the cellar.

There was a slight exclamation from The Thinking Machine, and this was followed immediately by the sharp, unmistakable click of a revolver somewhere behind them in the dark.

“Down, quick,” gasped Hatch, and with a sudden blow he dashed aside the electric light, extinguishing it. Simultaneously with this there came a revolver shot, and a bullet was buried in the wall behind Hatch’s head.
4

The reverberation of the pistol shot was still ringing in Hatch’s ears when he felt the hand of The Thinking Machine on his arm, and then through the utter blackness of the cellar came the irritable voice of the scientist:

“To your right, to your right,” it said sharply.

Then, contrary to this advice Hatch felt the scientist drawing him to the left. In another moment there came a second shot, and by the flash Hatch could see that it was aimed at a point a dozen feet to the right of the point where they had been when the first shot was fired. The person with the revolver had heard the scientist and had been duped.

Firmly the scientist drew Hatch on until they were almost to the cellar steps. There, outlined against a dim light which came down the stairs, they could see a tall figure peering through the darkness toward a spot opposite where they stood. Hatch saw only one thing to do and did it. He leaped forward and landed on the back of the figure, bearing the man to the ground. An instant later his hand closed on the revolver and he wrested it away.

“All right,” he sang out. “I’ve got it.”

The electric light which he had dashed from the hand of The Thinking Machine gleamed again through the cellar and fell upon the face of John Stockton, helpless and gasping in the hands of the reporter.

“Well?” asked Stockton calmly. “Are you burglars or what?”

“Let’s go upstairs to the light,” suggested The Thinking Machine.

It was under these peculiar circumstances that the scientist came face to face for the first time with John Stockton. Hatch introduced the two men in a most matter-of-fact tone and restored to Stockton the revolver. This was suggested by a nod of the scientist’s head. Stockton laid the revolver on a table.

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