As Minna Pitts led us through the large mansion preparatory to turning us over to a servant she explained hastily that Mr. Pitts had long been ill and was now taking a new treatment under Dr. Thompson Lord. No one having answered her bell in the present state of excitement of the house, she stopped short at the pivoted door of the kitchen, with a little shudder at the tragedy, and stood only long enough to relate to us the story as she had heard it from the valet, Edward.

Mr. Pitts, it seemed, had wanted an early breakfast and had sent Edward to order it. The valet had found the kitchen a veritable slaughter-house, with, the negro chef, Sam, lying dead on the floor. Sam had been dead, apparently, since the night before.

As she hurried away, Kennedy pushed open the door. It was a marvellous place, that antiseptic or rather aseptic kitchen, with its white tiling and enamel, its huge ice-box, and cooking-utensils for every purpose, all of the most expensive and modern make.

There were marks everywhere of a struggle, and by the side of the chef, whose body now lay in the next room awaiting the coroner, lay a long carving-knife with which he had evidently defended himself. On its blade and haft were huge coagulated spots of blood. The body of Sam bore marks of his having been clutched violently by the throat, and in his head was a single, deep wound that penetrated the skull in a most peculiar manner. It did not seem possible that a blow from a knife could have done it. It was a most unusual wound and not at all the sort that could have been made by a bullet.

As Kennedy examined it, he remarked, shaking his head in confirmation of his own opinion, "That must have been done by a Behr bulletless gun."

"A bulletless gun?" I repeated.

"Yes, a sort of pistol with a spring-operated device that projects a sharp blade with great force. No bullet and no powder are used in it. But when it is placed directly over a vital point of the skull so that the aim is unerring, a trigger lets a long knife shoot out with tremendous force, and death is instantaneous."

Near the door, leading to the courtyard that opened on the side street, were some spots of blood. They were so far from the place where the valet had discovered the body of the chef that there could be no doubt that they were blood from the murderer himself. Kennedy's reasoning in the matter seemed irresistible.

He looked under the table near the door, covered with a large light cloth. Beneath the table and behind the cloth he found another blood spot.

"How did that land there?" he mused aloud. "The table-cloth is bloodless."

Craig appeared to think a moment. Then he unlocked and opened the door.
A current of air was created and blew the cloth aside.

"Clearly," he exclaimed, "that drop of blood was wafted under the table as the door was opened. The chances are all that it came from a cut on perhaps the hand or face of the murderer himself."

It seemed to be entirely reasonable, for the bloodstains about the room were such as to indicate that he had been badly cut by the carving-knife.

"Whoever attacked the chef must have been deeply wounded," I remarked, picking up the bloody knife and looking about at the stains, comparatively few of which could have come from the one deep fatal wound in the head of the victim.

Kennedy was still engrossed in a study of the stains, evidently considering that their size, shape, and location might throw some light on what had occurred. "Walter," he said finally, "while I'm busy here, I wish you would find that valet, Edward. I want to talk to him."

I found him at last, a clean-cut young fellow of much above average intelligence.

"There are some things I have not yet got clearly, Edward," began
Kennedy. "Now where was the body, exactly, when you opened the door?"

Edward pointed out the exact spot, near the side of the kitchen toward the door leading out to the breakfast room and opposite the ice-box.

"And the door to the side street?" asked Kennedy, to all appearances very favorably impressed by the young man.

"It was locked, sir," he answered positively.

Kennedy was quite apparently considering the honesty and faithfulness of the servant. At last he leaned over and asked quickly, "Can I trust you?"

The frank, "Yes," of the young fellow was convincing enough.

"What I want," pursued Kennedy, "is to have some one inside this house who can tell me as much as he can see of the visitors, the messengers that come here this morning. It will be an act of loyalty to your employer, so that you need have no fear about that."

Edward bowed, and left us. While I had been seeking him, Kennedy had telephoned hastily to his laboratory and had found one of his students there. He had ordered him to bring down an apparatus which he described, and some other material.

While we waited Kennedy sent word to Pitts that he wanted to see him alone for a few minutes.

The instrument appeared to be a rubber bulb and cuff with a rubber bag attached to the inside. From it ran a tube which ended in another graduated glass tube with a thin line of mercury in it like a thermometer.

Craig adjusted the thing over the brachial artery of Pitts, just above the elbow.

"It may be a little uncomfortable, Mr. Pitts," he apologised, "but it will be for only a few minutes."

Pressure through the rubber bulb shut off the artery so that Kennedy could no longer feel the pulse at the wrist. As he worked, I began to see what he was after. The reading on the graded scale of the height of the column of mercury indicated, I knew, blood pressure. This time, as he worked, I noted also the flabby skin of Pitts as well as the small and sluggish pupils of his eyes.

He completed his test in silence and excused himself, although as we went back to the kitchen I was burning with curiosity.

"What was it?" I asked. "What did you discover?"

"That," he replied, "was a sphygmomanometer, something like the sphygmograph which we used once in another case. Normal blood pressure is 125 millimetres. Mr. Pitts shows a high pressure, very high. The large life insurance companies are now using this instrument. They would tell you that a high pressure like that indicates apoplexy. Mr. Pitts, young as he really is, is actually old. For, you know, the saying is that a man is as old as his arteries. Pitts has hardening of the arteries, arteriosclerosis—perhaps other heart and kidney troubles, in short pre-senility."

Craig paused: then added sententiously as if to himself: "You have heard the latest theories about old age, that it is due to microbic poisons secreted in the intestines and penetrating the intestinal walls? Well, in premature senility the symptoms are the same as in senility, only mental acuteness is not so impaired."

We had now reached the kitchen again. The student had also brought down to Kennedy a number of sterilised microscope slides and test-tubes, and from here and there in the masses of blood spots Kennedy was taking and preserving samples. He also took samples of the various foods, which he preserved in the sterilised tubes.

While he was at work Edward joined us cautiously.

"Has anything happened?" asked Craig.

"A message came by a boy for Mrs. Pitts," whispered the valet.

"What did she do with it?"

"Tore it up."

"And the pieces?"

"She must have hidden them somewhere."

"See if you can get them."

Edward nodded and left us.

"Yes," I remarked after he had gone, "it does seem as if the thing to do was to get on the trail of a person bearing wounds of some kind. I notice, for one thing, Craig, that Edward shows no such marks, nor does any one else in the house as far as I can see. If it were an 'inside job' I fancy Edward at least could clear himself. The point is to find the person with a bandaged hand or plastered face."

Kennedy assented, but his mind was on another subject. "Before we go we must see Mrs. Pitts alone, if we can," he said simply.

In answer to his inquiry through one of the servants she sent down word that she would see us immediately in her sitting-room. The events of the morning had quite naturally upset her, and she was, if anything, even paler than when we saw her before.

"Mrs. Pitts," began Kennedy, "I suppose you are aware of the physical condition of your husband?"

It seemed a little abrupt to me at first, but he intended it to be.
"Why," she asked with real alarm, "is he so very badly?"

"Pretty badly," remarked Kennedy mercilessly, observing the effect of his words. "So badly, I fear, that it would not require much more excitement like to-day's to bring on an attack of apoplexy. I should advise you to take especial care of him, Mrs. Pitts."

Following his eyes, I tried to determine whether the agitation of the woman before us was genuine or not. It certainly looked so. But then, I knew that she had been an actress before her marriage. Was she acting a part now?

"What do you mean?" she asked tremulously.

"Mrs. Pitts," replied Kennedy quickly, observing still the play of emotion on her delicate features, "some one, I believe, either regularly in or employed in this house or who had a ready means of access to it must have entered that kitchen last night. For what purpose, I can leave you to judge. But Sam surprised the intruder there and was killed for his faithfulness."

Her startled look told plainly that though she might have suspected something of the sort she did not think that any one else suspected, much less actually perhaps knew it.

"I can't imagine who it could be, unless it might be one of the servants," she murmured hastily; adding, "and there is none of them that I have any right to suspect."

She had in a measure regained her composure, and Kennedy felt that it was no use to pursue the conversation further, perhaps expose his hand before he was ready to play it.

"That woman is concealing something," remarked Kennedy to me as we left the house a few minutes later.

"She at least bears no marks of violence herself of any kind," I commented.

"No," agreed Craig, "no, you are right so far." He added: "I shall be very busy in the laboratory this afternoon, and probably longer. However, drop in at dinner time, and in the meantime, don't say a word to any one, but just use your position on the Star to keep in touch with anything the police authorities may be doing."

It was not a difficult commission, since they did nothing but issue a statement, the net import of which was to let the public know that they were very active, although they had nothing to report.

Kennedy was still busy when I rejoined him, a little late purposely, since I knew that he would be over his head in work.

"What's this—a zoo?" I asked, looking about me as I entered the sanctum that evening.

There were dogs and guinea pigs, rats and mice, a menagerie that would have delighted a small boy. It did not look like the same old laboratory for the investigation of criminal science, though I saw on a second glance that it was the same, that there was the usual hurly-burly of microscopes, test-tubes, and all the paraphernalia that were so mystifying at first but in the end under his skilful hand made the most complicated cases seem stupidly simple.

Craig smiled at my surprise. "I'm making a little study of intestinal poisons," he commented, "poisons produced by microbes which we keep under more or less control in healthy life. In death they are the little fellows that extend all over the body and putrefy it. We nourish within ourselves microbes which secrete very virulent poisons, and when those poisons are too much for us—well, we grow old. At least that is the theory of Metchnikoff, who says that old age is an infectious chronic, disease. Somehow," he added thoughtfully, "that beautiful white kitchen in the Pitts home had really become a factory for intestinal poisons."

There was an air of suppressed excitement in his manner which told me that Kennedy was on the trail of something unusual.

"Mouth murder," he cried at length, "that was what was being done in that wonderful kitchen. Do you know, the scientific slaying of human beings has far exceeded organised efforts at detection? Of course you expect me to say that; you think I look at such things through coloured glasses. But it is a fact, nevertheless.

"It is a very simple matter for the police to apprehend the common murderer whose weapon is a knife or a gun, but it is a different thing when they investigate the death of a person who has been the victim of the modern murderer who slays, let us say, with some kind of deadly bacilli. Authorities say, and I agree with them, that hundreds of murders are committed in this country every year and are not detected because the detectives are not scientists, while the slayers have used the knowledge of the scientists both to commit and to cover up the crimes. I tell you, Walter, a murder science bureau not only would clear up nearly every poison mystery, but also it would inspire such a wholesome fear among would-be murderers that they would abandon many attempts to take life."

He was as excited over the case as I had ever seen him. Indeed it was one that evidently taxed his utmost powers.

"What have you found?" I asked, startled.

"You remember my use of the sphygmomanometer?" he asked. "In the first place that put me on what seems to be a clear trail. The most dreaded of all the ills of the cardiac and vascular systems nowadays seems to be arterio-sclerosis, or hardening of the arteries. It is possible for a man of forty-odd, like Mr. Pitts, to have arteries in a condition which would not be encountered normally in persons under seventy years of age.

"The hard or hardening artery means increased blood pressure, with a consequent increased strain on the heart. This may lead, has led in this case, to a long train of distressing symptoms, and, of course, to ultimate death. Heart disease, according to statistics, is carrying off a greater percentage of persons than formerly. This fact cannot be denied, and it is attributed largely to worry, the abnormal rush of the life of to-day, and sometimes to faulty methods of eating and bad nutrition. On the surface, these natural causes might seem to be at work with Mr. Pitts. But, Walter, I do not believe it, I do not believe it. There is more than that, here. Come, I can do nothing more to-night, until I learn more from these animals and the cultures which I have in these tubes. Let us take a turn or two, then dine, and perhaps we may get some word at our apartment from Edward."

It was late that night when a gentle tap at the door proved that Kennedy's hope had not been unfounded. I opened it and let in Edward, the valet, who produced the fragments of a note, torn and crumpled.

"There is nothing new, sir," he explained, "except that Mrs. Pitts seems more nervous than ever, and Mr. Pitts, I think, is feeling a little brighter."

Kennedy said nothing, but was hard at work with puckered brows at piecing together the note which Edward had obtained after hunting through the house. It had been thrown into a fireplace in Mrs. Pitts's own room, and only by chance had part of it been unconsumed. The body of the note was gone altogether, but the first part and the last part remained.

Apparently it had been written the very morning on which the murder was discovered.

It read simply, "I have succeeded in having Thornton declared …" Then there was a break. The last words were legible, and were,"… confined in a suitable institution where he can cause no future harm."

There was no signature, as if the sender had perfectly understood that the receiver would understand.

"Not difficult to supply some of the context, at any rate," mused Kennedy. "Whoever Thornton may be, some one has succeeded in having him declared 'insane,' I should supply. If he is in an institution near New York, we must be able to locate him. Edward, this is a very important clue. There is nothing else."

Kennedy employed the remainder of the night in obtaining a list of all the institutions, both public and private, within a considerable radius of the city where the insane might be detained.

The next morning, after an hour or so spent in the laboratory apparently in confirming some control tests which Kennedy had laid out to make sure that he was not going wrong in the line of inquiry he was pursuing, we started off in a series of flying visits to the various sanitaria about the city in search of an inmate named Thornton.

I will not attempt to describe the many curious sights and experiences we saw and had. I could readily believe that any one who spent even as little time as we did might almost think that the very world was going rapidly insane. There were literally thousands of names in the lists which we examined patiently, going through them all, since Kennedy was not at all sure that Thornton might not be a first name, and we had no time to waste on taking any chances.

It was not until long after dusk that, weary with the search and dust-covered from our hasty scouring of the country in an automobile which Kennedy had hired after exhausting the city institutions, we came to a small private asylum up in Westchester. I had almost been willing to give it up for the day, to start afresh on the morrow, but Kennedy seemed to feel that the case was too urgent to lose even twelve hours over.

It was a peculiar place, isolated, out-of-the-way, and guarded by a high brick wall that enclosed a pretty good sized garden.

A ring at the bell brought a sharp-eyed maid to the door.

"Have you—er—any one here named Thornton—er—?" Kennedy paused in such a way that if it were the last name he might come to a full stop, and if it were a first name he could go on.

"There is a Mr. Thornton who came yesterday," she snapped ungraciously, "but you can not see him, It's against the rules."

"Yes—yesterday," repeated Kennedy eagerly, ignoring her tartness. "Could I—" he slipped a crumpled treasury note into her hand—"could I speak to Mr. Thornton's nurse?"

The note seemed to render the acidity of the girl slightly alkaline. She opened the door a little further, and we found ourselves in a plainly furnished reception room, alone.

We might have been in the reception-room of a prosperous country gentleman, so quiet was it. There was none of the raving, as far as I could make out, that I should have expected even in a twentieth century Bedlam, no material for a Poe story of Dr. Tarr and Professor Feather.

At length the hall door opened, and a man entered, not a prepossessing man, it is true, with his large and powerful hands and arms and slightly bowed, almost bulldog legs. Yet he was not of that aggressive kind which would make a show of physical strength without good and sufficient cause.

"You have charge of Mr. Thornton?" inquired Kennedy.

"Yes," was the curt response.

"I trust he is all right here?"

"He wouldn't be here if he was all right," was the quick reply. "And who might you be?"

"I knew him in the old days," replied Craig evasively. "My friend here does not know him, but I was in this part of Westchester visiting and having heard he was here thought I would drop in, just for old time's sake. That is all."

"How did you know he was here?" asked the man suspiciously.

"I heard indirectly from a friend of mine, Mrs. Pitts."

"Oh."

The man seemed to accept the explanation at its face value.

"Is he very—very badly?" asked Craig with well-feigned interest.

"Well," replied the man, a little mollified by a good cigar which I produced, "don't you go a-telling her, but if he says the name Minna once a day it is a thousand times. Them drug-dopes has some strange delusions."

"Strange delusions?" queried Craig. "Why, what do you mean?"

"Say," ejaculated the man. "I don't know you, You come here saying you're friends of Mr. Thornton's. How do I know what you are?"

"Well," ventured Kennedy, "suppose I should also tell you I am a friend of the man who committed him."

"Of Dr. Thompson Lord?"

"Exactly. My friend here knows Dr. Lord very well, don't you, Walter?"

Thus appealed to I hastened to add, "Indeed I do." Then, improving the opening, I hastened: "Is this Mr. Thornton violent? I think this is one of the most quiet institutions I ever saw for so small a place."

The man shook his head.

"Because," I added, "I thought some drug fiends were violent and had to be restrained by force, often."

"You won't find a mark or a scratch on him, sir," replied the man.
"That ain't our system."

"Not a mark or scratch on him," repeated Kennedy thoughtfully. "I wonder if he'd recognise me?"

"Can't say," concluded the man. "What's more, can't try. It's against the rules. Only your knowing so many he knows has got you this far. You'll have to call on a regular day or by appointment to see him, gentlemen."

There was an air of finality about the last statement that made Kennedy rise and move toward the door with a hearty "Thank you, for your kindness," and a wish to be remembered to "poor old Thornton."

As we climbed into the car he poked me in the ribs. "Just as good for the present as if we had seen him," he exclaimed. "Drug-fiend, friend of Mrs. Pitts, committed by Dr. Lord, no wounds."

Then he lapsed into silence as we sped back to the city.

"The Pitts house," ordered Kennedy as we bowled along, after noting by his watch that it was after nine. Then to me he added, "We must see Mrs. Pitts once more, and alone."

We waited some time after Kennedy sent up word that he would like to see Mrs. Pitts. At last she appeared. I thought she avoided Kennedy's eye, and I am sure that her intuition told her that he had some revelation to make, against which she was steeling herself.

Craig greeted her as reassuringly as he could, but as she sat nervously before us, I could see that she was in reality pale, worn, and anxious.

"We have had a rather hard day," began Kennedy after the usual polite inquiries about her own and her husband's health had been, I thought, a little prolonged by him.

"Indeed?" she asked. "Have you come any closer to the truth?"

Kennedy met her eyes, and she turned away.

"Yes, Mr. Jameson and I have put in the better part of the day in going from one institution for the insane to another."

He paused. The startled look on her face told as plainly as words that his remark had struck home.

Without giving her a chance to reply, or to think of a verbal means of escape, Craig hurried on with an account of what we had done, saying nothing about the original letter which had started us on the search for Thornton, but leaving it to be inferred by her that he knew much more than he cared to tell.

"In short, Mrs. Pitts," he concluded firmly, "I do not need to tell you that I already know much about the matter which you are concealing."

The piling up of fact on fact, mystifying as it was to me who had as yet no inkling of what it was tending toward, proved too much for the woman who knew the truth, yet did not know how much Kennedy knew of it. Minna Pitts was pacing the floor wildly, all the assumed manner of the actress gone from her, yet with the native grace and feeling of the born actress playing unrestrained in her actions.

"You know only part of my story," she cried, fixing him with her now tearless eyes. "It is only a question of time when you will worm it all out by your uncanny, occult methods. Mr. Kennedy, I cast myself on you."