The city lights were springing up block after block along Pennsylvania Avenue as Detective Ferguson left that busy thoroughfare and hurried to the Saratoga. He stepped inside the lobby of the apartment house a full minute before his appointment with its manager, and went at once to look him up. Before he could carry out his purpose he was joined by Harry Kent.

“Finley had to go out,” the latter explained. “I told him I would go up to Rochester's apartment with you.”

Ferguson thoughtfully caressed his clean-shaven jaw for a second, then came to a rapid decision.

“Lead the way, sir,” he said. “I'll follow.” Kent found him a silent companion while in the elevator and when walking down the corridor to Rochester's apartment, but once inside the living room, with the outer door tightly closed, Ferguson tossed down his hat and his whole demeanor changed.

“Sit down, Mr. Kent.” He selected a chair near Rochester's desk for himself, as Kent found another. “Let's thrash this thing out; are you working with me or against me?”

“Why do you ask?” Kent's surprise at the question was evident.

“Because every time I arrange to examine this apartment or inquire into Rochester's whereabouts you show up.” Ferguson's small eyes were trying to out-stare Kent, but the latter's clear gaze did not drop before his. “Are you aiding Philip Rochester in his efforts to elude arrest?”

“I am not,” declared Kent emphatically. “What prompts the question?”

“The fact that you are Rochester's partner,” Ferguson pointed out; his manner was still stiff. “It would be only natural for you to help him disappear out of friendship, or”—with a sidelong glance—“from a desire to hush up a scandal.”

“On the contrary I want Rochester found and every bit of evidence against him sifted out and aired,” retorted Kent. “Two heads are better than one, Ferguson; let us work together. Rochester must be located within the next twenty-four hours.”

Ferguson debated a moment, but Kent's speech as well as his manner indicated his sincerity, and the detective shook off his suspicions. “Have you had any further news of your partner?” he asked.

“No; that is”—recalling the scene in the bank early that afternoon—“nothing that relates to Rochester's present whereabouts. Now, Ferguson, to put your charges against Rochester in concrete form, you believe that he was insanely jealous of Jimmie Turnbull, that he recognized him in the Police Court in his burglar disguise, slipped a dose of aconitine in a glass of water which Turnbull drank, and after declaring that his friend had died from angina pectoris, disappeared. Is that all the case you have against him?”

“At present, yes,” admitted the detective cautiously.

“All circumstantial evidence—”

“But it will hold in court—”

“Ah, will it?” questioned Kent. “There's one big flaw in your case, Ferguson; the poison used to kill Turnbull.”

“Aconitine?”

“Exactly. Your theory is that Rochester slipped the poison in the glass of water on recognizing Turnbull in the police court; now, it is stretching probability to suppose that Rochester, a strong healthy man, was carrying that drug around in his vest pocket.”

Ferguson sat forward in his chair, his eyes glittering. “Do you mean to say that you think the murder of Turnbull was premeditated and not committed on the spur of the moment?” he asked.

“The fact that aconitine was used convinces me of that,” answered Kent.

Ferguson thought a moment. “If that is the case,” he said, grudgingly, “it sort of squashes the charge against Philip Rochester.”

“It would seem to,” agreed Kent. “But every shred of evidence I find points to Rochester as the guilty man.”

Ferguson edged his chair forward. “What have you discovered?” he demanded eagerly.

“This,” Kent spoke with increased earnestness. “That Philip Rochester is apparently a bankrupt, that he has over-drawn his private account at the Metropolis Trust Company, and withdrawn our partnership funds from the same bank.”

“Your partnership funds!” echoed the detective, eyeing Kent sharply. “How did you come to let him do that?”

“I was not aware that he had done so until Mr. Clymer told me of the transaction this afternoon,” answered Kent.

“You did not know”—Ferguson looked at him in dawning comprehension. “You mean Rochester absconded with the funds?”

“Some one forged my name to checks drawn on the firm's account,” Kent continued. “I understood they were made payable to cash and presented by Rochester on the day of Turnbull's death.”

Ferguson whistled as a slight vent to his feelings. “So you suspect Rochester of being a forger?” Kent made no reply, and he added; after a moment's deliberation, “What bearing has this discovery on Turnbull's death, aside from Rochester's need of funds to make a clean disappearance?”

“If it is true that Rochester was financially embarrassed and forged checks on the Metropolis Trust Company, it establishes another motive for the killing of Turnbull,” argued Kent. “Turnbull was cashier of that bank.”

“I see; he may have discovered the forgeries—but hold on.” Ferguson checked his rapid speech. “When were these forged checks presented at the bank?”

“Tuesday afternoon.”

Ferguson's face fell. “Pshaw! man; that was after Turnbull's death—how could he detect the forgeries?”

Kent did not reply at once; instead, he glanced keenly about the living room. The detective had only switched on one of the reading lamps and the greater part was in shadow. It was a pleasant and home-like room, and Kent was conscious of a keener pang for the loss of Jimmie Turnbull and the disappearance of Philip Rochester, as he gazed around. The lawyer and the bank cashier had been, until that winter, congenial comrades, sharing their business success and their apartment in complete accord; and now a shadow as black as that enveloping the unlighted apartment hung over their good names, threatening one or the other with the charge of forgery and of murder. Kent sighed and turned back to the silent detective.

“I can best answer your question by telling you that the day after Jimmie Turnbull died Mr. Clymer sent for me,” he began. “I found Colonel McIntyre with him and was told that the Colonel had lost valuable securities left at the bank. These securities had been given by the treasurer of the bank to Jimmie Turnbull when he presented a letter from Colonel McIntyre instructing the bank to surrender the securities to Jimmie.”

“Well?” questioned Ferguson. “Go on, sir.”

“That letter was a forgery.” Kent sat back and watched the detective's rapidly changing expression. “And no trace has been found of the Colonel's securities, last known to be in the possession of Turnbull.”

“Great heavens!” ejaculated Ferguson. “Which was the forger—Turnbull or Rochester?”

Kent shook a puzzled head. “That is for us to discover,” he said soberly. “Colonel McIntyre contends that Turnbull forged the letter and stole the securities, then fearing his guilt would become known, committed still another crime—that of suicide, he could have swallowed a dose of aconitine while at the police court.”

“Well, I'll be—blessed!” ejaculated Ferguson. “But if he was the forger how does that square with Rochester's peculiar behavior? The checks bearing your forged signatures were presented, mind you, by Rochester after Turnbull's death?”

“It doesn't square,” acknowledged Kent frankly. “There is this to be said for Turnbull: he was the soul of honor, his affairs were found to be in excellent condition, he was drawing a good salary, his investments paying well—he did not need to acquire securities or money by resorting to forgery.”

“Whereas Philip Rochester was on the point of bankruptcy,” remarked Ferguson. “Do you suppose he forged Colonel McIntyre's letter and gave it to Turnbull, and the latter got the securities from the bank treasurer and handed them over to Rochester in good faith, supposing his room-mate would give the papers to Colonel McIntyre?”

Kent nodded in agreement. “It looks that way to me,” he said gloomily. “Philip Rochester stood well in the community, his law practice is large and lucrative, and if it had not been for his periods of idleness and—and”—hesitating—“passion for good living, he would never have run into debt.”

“But he got there.” Ferguson's laugh was contemptuous. “A desperate man will do anything, Mr. Kent.”

“I know,” Kent looked dubious. “I would believe him guilty if it were not for the use of aconitine—that shows premeditation on the part of the murderer.”

“And why shouldn't Rochester plan Turnbull's murder ahead of the scene in the police court?” argued Ferguson. “Wasn't he living in deadly fear of exposure? If he did not commit the murder, why did he run away? And if he is innocent, why doesn't he come forward and prove it?”

“He may not know that he is suspected of the crime,” retorted Kent, rising. “It is for us to find Rochester, and I suggest that we search this apartment thoroughly.”

“I have already done so,” objected Ferguson. “And there wasn't the faintest clew to his hiding place.”

“For all that I am not satisfied.” Kent walked over and switched on another light. “When I came here on Wednesday night I had a tussle with some man, but he escaped in the dark without my seeing him. I believe he was Rochester.”

“You are probably right.” Ferguson crossed the room. “And if he came back once, he may return again. Come ahead,” and he plunged into the first bedroom. The two men subjected each room to an exhaustive search, but their labors were their only reward; except for an accumulation of dust, the apartment was undisturbed. They had reached the kitchenette-pantry when the gong over their heads sounded loudly, and Kent, with a muttered exclamation hastened toward the front door of the apartment. Ferguson, intent on studying the “L” of the building as seen from the window, was hardly conscious of his departure, and some seconds elapsed before he turned toward the door. As he gained it, he saw a dark shape dart down the hall. With a bound Ferguson started in pursuit, and the next second grappled with the flying man just as the electric lights went out and they were plunged in darkness.

Suddenly Kent's voice echoed down the hall. “Come here quick, Ferguson!”

There was a note of urgency about his appeal, and Ferguson straining his muscles until the blood pounded in his temples, threw the struggling man into a tufted arm-chair which stood by the entrance to the small dining room, and drawing out his handcuffs, slipped them on securely. “Stay there,” Ferguson admonished his prisoner. “Or there will be worse coming to you,” and he thrust the muzzle of his revolver against the man's heaving chest to illustrate his meaning; then as Kent called again, he sped down the hall and brought up breathless at the front door. The light was still burning in the corridor, though not very brightly, and he saw Kent hand the grinning messenger boy a shiny quarter. Touching his battered cap the boy went whistling away. “Tell the elevator boy to report that a fuse has burned out in Mr. Rochester's apartment,” Ferguson called after him, and the lad waved his hand as he dashed into the elevator.

Paying no attention to the detective's call, Kent showed him a white envelope which bore the simple address:

“It's the identical envelope I found in your safe,” declared Ferguson.

“And which disappeared last night at the Club de Vingt.” Kent turned over the envelope. “See, the red seal.”

For a minute the men contemplated the seal with the large distinctive letter “B” in the center.

“Open the letter, sir,” Ferguson urged and Kent, his fingers fairly trembling, jerked and tore at the linen incased envelope; the flap ripped away and he opened the envelope—it was empty.

Instinctively the two men glanced down at the parquetry flooring; nothing but a thin coating of dust lay there, and Kent looked up and down the corridor; it was deserted.

“Do you recognize the handwriting?” asked Ferguson.

“No.” Kent regarded the envelope in bewilderment. “What shall we do?”

“Do? Call up the Dime Messenger Service and see where the envelope came from; but first come and see my prisoner.

“Your prisoner?” in profound astonishment.

“Yes. I caught him chasing up the hall after you,” explained Ferguson as they hurriedly retraced their steps. “I put handcuffs on him and then went to you. Ah, here's the light!”

“The light, yes; but where's your prisoner?” and Kent, who was a trifle in advance of his companion in reaching the dining room, stood aside to let Ferguson pass him.

The detective halted abruptly. The chair into which he had thrust his prisoner was vacant. The man had disappeared.

With one accord Ferguson and Kent advanced close to the chair, and an oath broke from the detective. On the cushion of the chair, still bearing the impress of a human body, lay a pair of shining new handcuffs.

Dazedly Ferguson stooped over and examined them. They were still securely locked. Wheeling around Kent dashed through the door to his right and Ferguson, collecting his wits, searched the rest of the apartment with minute care. Five minutes later he came face to face with Kent in the living room. “Not a trace of any kind,” declared Kent. “It's the same as the other night; the man's gone. It's—it's positively uncanny.”

Ferguson's face was red from mortification and his exertions combined.

“The fellow must have slipped from the room by that other door and out through the living room as we came down the hall,” he said. “Did you shut the door of the apartment, Mr. Kent, before coming down here to look at the prisoner?”

“Yes.” Kent led the way back to the dining room. “Did you recognize the man, Ferguson?”

“No.” The detective swore softly as he stared about the room. “The lights went out just as I tackled him.”

“It was beastly luck that the fuse burned out at that second,” groaned Kent. “Fortune was with him in that; but how did the man get free of the handcuffs?” pointing to them still lying in the chair. “We can't attribute that to luck, unless”—staring keenly at Ferguson—“unless you did not snap them on the man's wrists, after all.”

“I did; I swear it,” declared Ferguson. “I'm no novice at that business. Here, don't touch them, Mr. Kent,” as his companion bent toward the chair. “There may be finger marks on the steel; if so”—he drew out his handkerchief, and taking care not to handle the burnished metal, he folded the handcuffs carefully in it and put them in his coat pocket. “There's no use lingering here, Mr. Kent; this apartment is vacant now except for us. I must get to Headquarters.”

“Hadn't you better telephone for an operative and station him here?” suggested Kent.

“I did so while you were searching the back rooms,” replied Ferguson. “There,” as the gong sounded. “That's Nelson, now.”

But the person who stood in the outer corridor when they opened the front door was not Nelson, the operative, but Dr. Stone.

“Can I see Mr. Rochester?” he asked, then catching sight of Kent standing just back of the detective, he added, “Hello, Kent; I thought I heard some one walking about in here from my apartment next door, and concluded Rochester had returned. Can I see him?”

“N-no,” Kent spoke slowly, with a side-glance at the silent detective. “Rochester has been here—and left.”