Kennedy was reading a scientific treatise one morning, while I was banging on the typewriter, when a knock at the laboratory door disturbed us.

By some intuition, Craig seemed to know who it was. He sprang to open the door, and there stood Elaine Dodge and her lawyer, Perry Bennett.

Instantly, Craig read from the startled look on Elaine's face that something dreadful had happened.

"Why—what's the matter?" he asked, solicitously.

"A—another letter—from the Clutching Hand!" she exclaimed breathlessly. "Mr. Bennett was calling on me, when this note was brought in. We both thought we'd better see you at once about it and he was kind enough to drive me here right away in his car."

Craig took the letter and we both read, with amazement:

"Are you an enemy of society? If not, order Craig Kennedy to leave the country by nine o'clock to-morrow morning. Otherwise, a pedestrian will drop dead outside his laboratory every hour until he leaves."

The note was signed by the now familiar sinister hand, and had, added, a postscript, which read:

"As a token of his leaving, have him place a vase of flowers on his laboratory window to-day."

"What shall we do?" queried Bennett, evidently very much alarmed at the threat.

"Do?" replied Kennedy, laughing contemptuously at the apparently futile threat, "why, nothing. Just wait."

. . . . . . . .

The day proved uneventful and I paid no further attention to the warning letter. It seemed too preposterous to amount to anything.

Kennedy, however, with his characteristic foresight, as I learned afterwards, had not been entirely unprepared, though he had affected to treat the thing with contempt.

His laboratory, I may say, was at the very edge of the University buildings, with the campus back of it, but opening on the other side on a street that was ordinarily not overcrowded.

We got up as usual the next day and, quite early, went over to the laboratory. Kennedy, as was his custom, plunged straightway into his work and appeared absorbed by it, while I wrote.

"There IS something queer going on, Walter," he remarked. "This thing registers some kind of wireless rays—infra-red, I think,—something like those that they say that Italian scientist, Ulivi, claims he has discovered and called the 'F-rays.'"

"How do you know?" I asked, looking up from my work. "What's that instrument you are using?"

"A bolometer, invented by the late Professor Langley," he replied, his attention riveted on it.

Some time previously, Kennedy had had installed on the window ledge one of those mirror-like arrangements, known as a "busybody," which show those in a room what is going on on the street.

As I moved over to look at the bolometer, I happened to glance into the busybody and saw that a crowd was rapidly collecting on the sidewalk.

"Look, Craig!" I called hastily.

He hurried over to me and looked. We could both see in the busybody mirror a group of excited passersby bending over a man lying prostrate on the sidewalk.

He had evidently been standing on the curbstone outside the laboratory and had suddenly put his hand to his forehead. Then he had literally crumpled up into a heap, as he sank to the ground.

The excited crowd lifted him up and bore him away, and I turned in surprise to Craig. He was looking at his watch.

It was now only a few moments past nine o'clock!

Not quarter of an hour later, our door was excitedly flung open and
Elaine and Perry Bennett arrived.

"I've just heard of the accident," she cried, fearfully. "Isn't it terrible. What had we better do?"

For a few moments no one said a word. Then Kennedy began carefully examining the bolometer and some other recording instruments he had, while the rest of us watched, fascinated.

Somehow that "busybody" seemed to attract me. I could not resist looking into it from time to time as Kennedy worked.

I was scarcely able to control my excitement when, again, I saw the same scene enacted on the sidewalk before the laboratory. Hurriedly I looked at my watch. It was ten o'clock!

"Craig!" I cried. "Another!"

Instantly he was at my side, gazing eagerly. There was a second innocent pedestrian lying on the sidewalk while a crowd, almost panic-stricken, gathered about him.

We watched, almost stunned by the suddenness of the thing, until finally, without a word, Kennedy turned away, his face set in tense lines.

"It's no use," he muttered, as we gathered about him. "We're beaten. I can't stand this sort of thing. I will leave to-morrow for South America."

I thought Elaine Dodge would faint at the shock of his words coming so soon after the terrible occurrence outside. She looked at him, speechless.

It happened that Kennedy had some artificial flowers on a stand, which he had been using long before in the study of synthetic coloring materials. Before Elaine could recover her tongue, he seized them and stuck them into a tall beaker, like a vase. Then he deliberately walked to the window and placed the beaker on the ledge in a most prominent position.

Elaine and Bennett, to say nothing of myself, gazed at him, awe-struck.

"Is—is there no other way but to surrender?" she asked.

Kennedy mournfully shook his head.

"I'm afraid not," he answered slowly. "There's no telling how far a fellow who has this marvellous power might go. I think I'd better leave to save you. He may not content himself with innocent outsiders always."

Nothing that any of us could say, not even the pleadings of Elaine herself could move him. The thought that at eleven o'clock a third innocent passerby might lie stricken on the street seemed to move him powerfully.

When, at eleven, nothing happened as it had at the other two hours, he was even more confirmed in his purpose. Entreaties had no effect, and late in the morning, he succeeded in convincing us all that his purpose was irrevocable.

As we stood at the door, mournfully bidding our visitors farewell until the morrow, when he had decided to sail, I could see that he was eager to be alone. He had been looking now and then at the peculiar instrument which he had been studying earlier in the day and I could see on his face a sort of subtle intentness.

"I'm so sorry—Craig," murmured Elaine, choking back her emotion, and finding it impossible to go on.

"So am I, Elaine," he answered, tensely. "But—perhaps—when this trouble blows over—"

He paused, unable to speak, turned, and shook his head. Then with a forced gaiety he bade Elaine and Perry Bennett adieu, saying that perhaps a trip might do him good.

They had scarcely gone out and Kennedy closed the door carefully, when he turned and went directly to the instrument which I had seen him observing so interestedly.

Plainly, I could see that it was registering something.

"What's the matter?" I asked, non-plussed.

"Just a moment, Walter," he replied evasively, as if not quite sure of himself.

He walked fairly close to the window this time, keeping well out of the direct line of it, however, and there stood gazing out into the street.

A glint, as if of the sun shining on a pair of opera glasses could be seen from a window across the way.

"We are being watched," he said slowly, turning and looking at me fixedly, "but I don't dare investigate lest it cost the lives of more unfortunates."

He stood for a moment in deep thought. Then he pulled out a suitcase and began silently to pack it.

. . . . . . . .

Although we had not dared to investigate, we knew that from a building, across the street, emissaries of the Clutching Hand were watching for our signal of surrender.

The fact was, as we found out later, that in a poorly furnished room, much after the fashion of that which, with the help of the authorities, we had once raided in the suburbs, there were at that moment two crooks.

One of them was the famous, or rather the infamous, Professor LeCroix, with whom in a disguise as a doctor we had already had some experience when he stole from the Hillside Sanitarium the twilight sleep drugs. The other was the young secretary of the Clutching Hand who had given the warning at the suburban headquarters at the time when they were endeavoring to transfuse Elaine Dodge's blood to save the life of the crook whom she had shot.

This was the new headquarters of the master criminal, very carefully guarded.

"Look!" cried LeCroix, very much elated at the effect that had been produced by his infra-red rays, "There is the sign—the vase of flowers. We have got him this time!"

LeCroix gleefully patted a peculiar instrument beside him. Apparently it was a combination of powerful electric arcs, the rays of which were shot through a funnel-like arrangement into a converter or, rather, a sort of concentration apparatus from which the dread power could be released through a tube-like affair at one end. It was his infra-red heat wave, F-ray, engine.

"I told you—it would work!" cried LeCroix.

. . . . . . . .

I did not argue any further with Craig about his sudden resolution to go away. But it is a very solemn proceeding to pack up and admit defeat after such a brilliant succession of cases as had been his until we met this master criminal.

He was unshakeable, however, and the next morning we closed the laboratory and loaded our baggage, which was considerable, on a taxicab.

Neither of us said much, but I saw a quick look of appreciation on Craig's face as we pulled up at the wharf and saw that the Dodge car was already there. He seemed deeply moved that Elaine should come at such an early hour to have a last word.

Our cab stopped and Kennedy moved over toward her car, directing two
porters, whom I noticed that he chose with care, to wait at one side.
One of them was an old Irishman with a slight limp; the other a wiry
Frenchman with a pointed beard.

In spite of her pleadings, however, Kennedy held to his purpose and, as we shook hands for the last time, I thought that Elaine would almost break down.

"Here, you fellows, now," directed Craig, turning brusquely to the porters, "hustle that baggage right aboard."

"Can't we go on the ship, too?" asked Elaine, appealingly.

"I'm sorry—I'm afraid there isn't time," apologized Craig.

We finally tore ourselves away, followed by the porters carrying as much as they could.

"Bon voyage!" cried Elaine, bravely keeping back a choke in her voice.

Near the gangplank, in the crowd, I noticed a couple of sinister faces watching the ship's officers and the passengers going aboard. Kennedy's quick eye spotted them, too, but he did not show in any way that he noticed anything as, followed by our two porters, we quickly climbed the gangplank.

A moment Craig paused by the rail and waved to Elaine and Bennett who returned the salute feelingly. I paused at the rail, too, speculating how we were to get the rest of our baggage aboard in time, for we had taken several minutes saying good-bye.

"In there," pointed Kennedy quickly to the porters, indicating our stateroom which was an outside room. "Come, Walter."

I followed him in with a heavy heart.

. . . . . . . .

Outside could be seen the two sinister faces in the crowd watching intently, with eyes fixed on the stateroom. Finally one of the crooks boarded the ship hastily, while the other watched the two porters come out of the stateroom and pause at the window, speaking back into the room as though answering commands.

Then the porters quickly ran along the deck and down the plank, to get the rest of the luggage. As they approached the Dodge car, Elaine, Aunt Josephine and Perry Bennett were straining their eyes to catch a last glimpse of us.

The porters took a small but very heavy box and, lugging and tugging, hastened toward the boat with it. But they were too late. The gang plank was being hauled in.

They shouted, but the ship's officers waved them back.

"Too late!" one of the deckhands shouted, a little pleased to see that someone would be inconvenienced for tardiness.

The porters argued. But it was no use. All they could do was to carry the box back to the Dodge car.

Miss Dodge was just getting in as they returned.

"What shall we do with this and the other stuff?" asked the Irish porter.

She looked at the rest of the tagged luggage and the box which was marked:

Scientific Instruments Valuable Handle with care.

"Here—pile them in here," she said indicating the taxicab. "I'll take charge of them."

Meanwhile one of our sinister faced friends had just had time to regain the shore after following us aboard ship and strolling past the window of our stateroom. He paused long enough to observe one of the occupants studying a map, while the other was opening a bag.

"They're gone!" he said to the other as he rejoined him on the dock, giving a nod of his head and a jerk of his thumb at the ship.

"Yes," added the other crook, "and lost most of their baggage, too."

. . . . . . . .

Slowly the Dodge car proceeded through the streets up from the river front, followed by the taxicab, until at last the Dodge mansion, was reached.

There Elaine and Aunt Josephine got out and Bennett stood talking with them a moment. Finally he excused himself reluctantly for it was now late, even for a lawyer, to get to his office.

As he hurried over to the subway, Elaine nodded to the porters in the taxicab, "Take that stuff in the house. We'll have to send it by the next boat."

Then she followed Aunt Josephine while the porters unloaded the boxes and bags.

Elaine sighed moodily as she walked slowly in.

"Here, Marie," she cried petulantly to her maid, "take these wraps of mine."

Marie ventured no remark, but, like a good servant, took them.

A moment later Aunt Josephine left her and Elaine went into the library and over to a table. She stood there an instant, then sank down into a chair, taking up Kennedy's picture and gazing at it with eyes filled by tears.

Just then Jennings came into the room, ushering the two porters laden with the boxes and bags.

"Where shall I have them put these things, Miss Elaine?" he inquired.

"Oh—anywhere," she answered hurriedly, replacing the picture.

Jennings paused. As he did so, one of the porters limped forward. "I've a message for you, Miss," he said in a rich Irish brogue, with a look at Jennings, "to be delivered in private."

Elaine glanced at him surprised. Then she nodded to Jennings who disappeared. As he did so, the Irishman limped to the door and drew together the portieres.

Then he came back closer to Elaine.

A moment she looked at him, not quite knowing from his strange actions whether to call for help or not.

. . . . . . . .

At a motion from Kennedy, as he pulled off his wig, I pulled off the little false beard.

Elaine looked at us, transformed, startled.

"Wh—what—" she stammered. "Oh—I'm—so—glad. How—"

Kennedy said nothing. He was thoroughly enjoying her face.

"Don't you understand?" I explained, laughing merrily. "I admit that I didn't until that last minute in the stateroom on the boat when we didn't come back to wave a last good-bye. But all the care that Craig took in selecting the porters was the result of work he did yesterday, and the insistence with which he chose our travelling clothes had a deep-laid purpose."

She said nothing, and I continued.

"The change was made quickly in the stateroom. Kennedy's man threw on the coat and hat he wore, while Craig donned the rough clothes of the porter and added a limp and a wig. The same sort of exchange of clothes was made by me and Craig clapped a Van Dyck beard on my chin."

"I—I'm so glad," she repeated. "I didn't think you'd—"

She cut the sentence short, remembering her eyes and the photograph as we entered, and a deep blush crimsoned her face.

"Mum's the word," cautioned Kennedy, "You must smuggle us out of the house, some way."

. . . . . . . .

Kennedy lost no time in confirming the suspicions of his bolometer as to the cause of the death of the two innocent victims of the machinations of the Clutching Hand.

Both of them, he had learned, had been removed to a nearby undertaking shop, awaiting the verdict of the coroner. We sought out the shop and prevailed on the undertaker to let us see the bodies.

As Kennedy pulled down the shroud from the face of the first victim, he disclosed on his forehead a round dark spot about the size of a small coin. Quickly, he moved to the next coffin and, uncovering the face, disclosed a similar mark.

"What is it?" I asked, awestruck.

"Why," he said, "I've heard of a certain Viennese, one LeCroix I believe, who has discovered or perfected an infra-red ray instrument which shoots its power a great distance with extreme accuracy and leaves a mark like these."

"Is he in New York?" I inquired anxiously.

"Yes, I believe he is."

Kennedy seemed indisposed to answer more until he knew more, and I saw that he would prefer not being questioned for the present.

We thanked the undertaker for his courtesy and went out.

. . . . . . . .

Meanwhile Elaine had called up Perry Bennett.

"Mr. Bennett," she exclaimed over the wire, "just guess who called on me?"

"Who?" he answered, "I give it up."

"Mr. Kennedy and Mr. Jameson," she called back.

"Is that so?" he returned. "Isn't that fine? I didn't think he was the kind to run away like that. How did it happen?"

Elaine quickly told the story as I had told her.

Had she known it, however, Bennett's valet, Thomas, was at that very moment listening at the door, intensely interested.

As Bennett hung up the receiver, Thomas entered the room.

"If anyone calls me," ordered Bennett, "take the message, particularly if it is from Miss Dodge. I must get downtown—and tell her after I finish my court work for the day I shall be right up."

"Yes sir," nodded the valet with a covert glance at his master.

Then, as Bennett left, he followed him to the door, paused, thought a moment, then, as though coming to a sudden decision, went out by an opposite door.

It was not long afterward that a knock sounded at the door of the new headquarters of the Clutching Hand. LeCroix and the secretary were there, as well as a couple of others.

"The Chief!" exclaimed one.

The secretary opened the door, and, sure enough, the Clutching Hand entered.

"Well, how did your infra-red rays work?" he asked LeCroix.

"Fine."

"And they're gone?"

"Yes. The flowers were in the window yesterday. Two of our men saw them on the boat."

There came another knock. This time, as the door opened, it was Thomas,
Bennett's faithless valet, who entered.

"Say," blurted out the informer, "do you know Kennedy and Jameson are back?"

"Back?" cried the crooks.

"Yes,—they didn't go. Changed clothes with the porters. I just heard
Miss Dodge telling Mr. Bennett."

Clutching Hand eyed him keenly, then seemed to burst into an ungovernable fury.

Quickly he began volleying orders at the valet and the others. Then, with the secretary and two of the other crooks he left by another door from that by which he had sent the valet forth.

. . . . . . . .

Leaving the undertaker's, Kennedy and I made our way, keeping off thoroughfares, to police headquarters, where, after making ourselves known, Craig made arrangements for a raid on the house across the street from the laboratory where we had seen the opera glass reflection.

Then, as secretly as we had come, we went out again, letting ourselves into the laboratory, stealthily looking up and down the street. We entered by a basement door, which Kennedy carefully locked again.

No sooner had we disappeared than one of the Clutching Hand's spies who had been watching behind a barrel of rubbish gave the signal of the hand down the street to a confederate and, going to the door, entered by means of a skeleton key.

We entered our laboratory which Kennedy had closed the day before. With shades drawn, it now looked deserted enough.

I dropped into a chair and lighted a cigarette with a sigh of relief, for really I had thought, until the boat sailed, that Kennedy actually contemplated going away.

Kennedy went over to a cabinet and, from it, took out a notebook and a small box. Opening the notebook on the laboratory table, he rapidly turned the pages.

"Here, Walter," he remarked. "This will answer your questions about the mysterious deadly ray."

I moved over to the table, eager to satisfy my curiosity and read the notes which he indicated with his finger.

INFRA-RED RAY NOTES

The infra-red ray which has been developed by LeCroix from the experiments of the Italian scientist Ulivi causes, when concentrated by an apparatus perfected by LeCroix, an instantaneous combustion of nonreflecting surfaces. It is particularly deadly in its effect on the brain centers.

It can be diverted, it is said however, by a shield composed of platinum backed by asbestos.

Next Kennedy opened the case which he had taken out of the cabinet and from it he took out the platinum-asbestos mirror, which was something of his own invention. He held it up and in pantomime showed me just how it would cut off the deadly rays.

He had not finished even that, when a peculiar noise in the laboratory itself disturbed him and he hastily thrust the asbestos platinum shield into his pocket.

Though we had not realized it, our return had been anticipated.

Suddenly, from a closet projected a magazine gun and before we could move, the Clutching Hand himself slowly appeared, behind us.

"Ah!" he exclaimed with mock politeness, "so, you thought you'd fool me, did you? Well!"

Just then, two other crooks, who had let themselves in by the skeleton key through the basement jumped into the room through that door covering us.

We started to our feet, but in an instant found ourselves both sprawling on the floor.

In the cabinet, beneath the laboratory table, another crook had been hidden and he tackled us with all the skill of an old football player against whom we had no defence.

Four of them were upon us instantly.

. . . . . . . .

At the same time, Thomas, the faithless valet of Bennett, had been dispatched by the Clutching Hand to commandeer his master's roadster in his absence, and, carrying out the instructions, he had driven up before Elaine's house at the very moment when she was going out for a walk.

Thomas jumped out of the car and touched his hat deferentially.

"A message from Mr. Bennett, ma'am," he explained. "Mr. Kennedy and Mr.
Bennett have sent me to ask you to come over to the laboratory."

Unsuspecting, Elaine stepped into the car and drove off.

Instead, however, of turning and pulling up on the laboratory side of the street, Thomas stopped opposite it. He got out and Elaine, thinking that perhaps it was to save time that he had not turned the car around, followed.

But when the valet, instead of crossing the street, went up to a door of a house and rang the bell, she began to suspect that all was not as it should be.

"What are you going here for, Thomas?" she asked. "There's the laboratory—over there."

"But, Miss Dodge," he apologized, "Mr. Kennedy and Mr. Bennett are here. They told me they'd be here."

The door was opened quickly by a lookout of the Clutching Hand and the valet asked if Craig and Elaine's lawyer were in. Of course the lookout replied that they were and, before Elaine knew it, she was jostled into the dark hallway and the door was banged shut.

Resistance was useless now and she was hurried along until another door was opened.

There she saw LeCroix and the other crooks.

And, as the door slammed, she caught sight of the fearsome Clutching
Hand himself.

She drew back, but was too frightened even to scream.

With a harsh, cruel laugh, the super-criminal beckoned to her to follow him and look down through a small trap door.

Unable now to resist, she looked.

There she saw us. To that extent the valet had told the truth. Kennedy was standing in deep thought, while I sat on an old box, smoking a cigarette—very miserable.

. . . . . . . .

Was this to be the sole outcome of Kennedy's clever ruse, I was wondering. Were we only to be shipwrecked in sight of port?

Watching his chance, when the street was deserted, the Clutching Hand and his followers had hustled us over to the new hangout across from the laboratory. There they had met more crooks and had thrust us into this vile hole. As the various ineffectual schemes for escape surged through my head, I happened to look up and caught a glance of horror on Craig's face. I followed his eyes. There, above us, was Elaine!

I saw her look from us to the Clutching Hand in terror. But none of us uttered a word.

"I will now show you, my dear young lady," almost hissed the Clutching Hand at length, "as pretty a game of hide and seek as you have ever seen."

As he said it, another trap door near the infra-red ray machine was opened and a beam of light burst through. I knew it was not that which we had to fear, but the invisible rays that accompanied it, the rays that had affected the bolometer.

Just then a spot of light showed near my foot, moving about the cement floor until it fell on my shoe. Instantly, the leather charred, even before I could move.

Kennedy and I leaped to our feet and drew back. The beam followed us.
We retreated further. Still it followed, inexorably.

Clutching Hand was now holding Elaine near the door where she could not help seeing, laughing diabolically while he directed LeCroix and the rest to work the infra-red ray apparatus through the trap.

As we dodged from corner to corner, endeavoring to keep the red ray from touching us, the crooks seemed in no hurry, but rather to enjoy prolonging the torture as does a cat with a mouse.

"Please—oh, please—stop!" begged Elaine.

Clutching Hand only laughed with fiendish delight and urged his men on.

The thing was getting closer and closer.

Suddenly we heard a strange voice ring out above us.

"Police!"

"Where?" growled the Clutching Hand in fury.

"Outside—a raid! Run! He's told them!"

Already we could hear the hammers and axes of the police whom Kennedy had called upon before, as they battered at the outside door.

At that door a moment before, the lookout suddenly had given a startled stare and a suppressed cry. Glancing down the street he had seen a police patrol in which were a score or more of the strongarm squad. They had jumped out, some carrying sledgehammers, others axes.

Almost before he could cry out and retreat to give a warning, they had reached the door and the first resounding blows had been struck.

The lookout quickly had fled and drawn the bolts of a strong inner door, and the police began battering that impediment.

Instantly, Clutching Hand turned to LeCroix at the F-ray machine.

"Finish them!" he shouted.

We were now backed up against a small ell in the wall of the cellar. It was barely large enough to hold us, but by crowding we were able to keep out of the reach of the ray. The ray shot past the ell and struck a wall a couple of inches from us.

I looked. The cement began to crumble under the intense heat.

Meanwhile, the police were having great difficulty with the steelbolt-studded door into the room. Still, it was yielding a bit.

"Hurry!" shouted Clutching Hand to LeCroix.

Kennedy had voluntarily placed himself in front of me in the ell. Carefully, to avoid the ray, he took the asbestos-platinum shield from his pocket and slid it forward as best he could over the wall to the spot where the ray struck.

It deflected the ray.

But so powerful was it that even that part of the ray which was deflected could be seen to strike the ceiling in the corner which was of wood. Instantly, before Kennedy could even move the shield, the wood burst into flames.

Above us now smoke was pouring into the room where the deflected ray struck the floor and flames broke out.

"Confound him!" ground out Clutching Hand, as they saw it.

The other crooks backed away and stood, hesitating, not knowing quite what to do.

The police had by this time finished battering in the door and had rushed into the outer passage.

While the flames leaped up, the crooks closed the last door into the room.

"Run!" shouted Clutching Hand, as they opened a secret gate disclosing a spiral flight of iron steps.

A moment later all had disappeared except Clutching Hand himself. The last door would hold only a few seconds, but Clutching Hand was waiting to take advantage of even that. With a last frantic effort he sought to direct the terrific ray at us. Elaine acted instantly. With all her strength she rushed forward, overturning the machine.

Clutching Hand uttered a growl and slowly raised his gun, taking aim with the butt for a well-directed blow at her head.

Just then the door yielded and a policeman stuck his head and shoulders through. His revolver rang out and Clutching Hand's automatic flew out of his grasp, giving him just enough time to dodge through and slam the secret door in the faces of the squad as they rushed in.

Back of the house, Clutching Hand and the other crooks were now passing through a bricked passage. The fire had got so far beyond control by this time that it drove the police back from their efforts to open the secret door. Thus the Clutching Hand had made good his escape through the passage which led out, as we later discovered, to the railroad tracks along the river.

"Down there—Mr. Kennedy—and Mr. Jameson," cried Elaine, pointing at the trap which was hidden in the stifle.

The fire had gained terrific headway, but the police seized a ladder and stuck it down into the basement.

Choking and sputtering, half suffocated, we staggered up.

"Are you hurt?" asked Elaine anxiously, taking Craig's arm.

"Not a bit—thanks to you!" he replied, forgetting all in meeting the eager questioning of her wonderful eyes.