David Curtis was not far behind Leonard McLane in reaching the hall and instinctively swung in the direction the latter was headed. Anne Meredith turned back from the head of the circular staircase at their approach.

“Oh, Doctor McLane!” she exclaimed. “I found poor Gretchen stretched out here in a dead faint. She is coming to, now. Thank you,” addressing Inspector Mitchell who, seated on the top step, supported the chambermaid’s head on his broad shoulder. “You were very kind.”

“Not at all, Miss Meredith.” Mitchell, considerably embarrassed by his role of nurse, gladly relinquished his place to McLane and Susanne, who at a sign from Anne helped to support the half-conscious Dutch girl.

Herman, standing in the square hall at the foot of the circular staircase, had heard the commotion and, with forethought, instantly provided himself with a glass of water and a smaller glass containing whisky.

Armed with these he appeared on the scene just as McLane, with the assistance of Susanne, had gotten Gretchen stretched out on a broad settee which stood in a window alcove off the corridor. Susanne placed a pillow under Gretchen’s head and loosened her black gown with a deftness which won an approving word from McLane. It took some persuasion to induce Gretchen to swallow some of the whisky and she made a wry face as the powerful stimulant slipped down her throat. It quickly dispelled the deadly faintness which had overcome her. Finally, satisfied that Gretchen would be able to go to her room, supported by Susanne, McLane left her and went over to the small group at the head of the staircase.

“What brought on Gretchen’s attack?” asked McLane, taking care to speak so as not to be overheard by either Susanne or the Dutch girl.

“I don’t know, doctor,” answered Anne. “She has been very nervous and unlike herself ever since the inquest.”

Inspector Mitchell, who had been regarding David Curtis as the latter stood by Anne’s side, with fixed scrutiny, broke into the conversation.

“I may have startled your maid unintentionally,” he said apologetically. “Herman told me that Doctor McLane was with Doctor Curtis and I came upstairs unannounced. It isn’t my custom to make much noise,” he smiled. “And your maid did not apparently know that I was near her. When she turned and saw me, she dropped where she stood.”

“Pardon, mademoiselle.” Susanne had left Gretchen and drawn nearer in time to catch Mitchell’s remark. “All las’ night and to-day have what you call ‘shadows’ followed poor Gretchen.”

“Shadows?” questioned Anne, frowning in her perplexity.

“Spies, if monsieur permits the word,” with a spiteful look at Inspector Mitchell. “The poor girl is distracted with fear.”

“What is she afraid of?” demanded Mitchell quickly.

Susanne partly turned her back on him without answering.

“Please, mademoiselle,” she began, addressing Anne, “Gretchen must have peace, or she be ill. She is a good girl.”

“She is!” Anne spoke with sudden energy. “Come, Inspector, there is no law which permits you to introduce spies into our household.”

“I beg your pardon,” Mitchell spoke stiffly. “We have not exceeded our rights. Investigations have to be conducted when a crime has been committed.”

“A crime?”

“Yes, madam; and the greatest crime of all—murder, cold-blooded premeditated murder.”

Curtis, standing close beside Anne, heard her sudden intake of breath, but she faced Mitchell with no other indication of emotion.

“You still contend that my uncle was murdered?” she asked. “And that it was not a case of suicide in a moment of mental aberration.”

“I do; the medical evidence establishes that fact.” Mitchell would have added more, but Anne turned swiftly to Curtis.

“Can you tell with absolute accuracy from the wound that it was not self-inflicted, Doctor Curtis?” she demanded.

All eyes were turned toward the blind surgeon. McLane, as well as Curtis, had caught the unconscious note of appeal in Anne’s voice, and he waited with interest for Curtis’ answer. It took the form of a question.

“Was John Meredith by chance ambidexterous?” he asked.

“He was.”

An exclamation escaped Mitchell. “Why didn’t you state that fact at the inquest?” he inquired with warmth.

“Because I was not questioned on the subject,” she responded, and again addressed Curtis. “Doesn’t that prove that Uncle John could have killed himself?”

Curtis’ hesitation was imperceptible except to McLane.

“I believe that the fact that Meredith was ambidexterous will enable experts to cast sufficient doubt on the medical testimony to render it practically valueless,” he said.

“Perhaps an expert can tear it to pieces,” broke in Mitchell. “But you can’t get over the fact that no weapon was found near the body. If John Meredith killed himself, what did he do with the weapon?”

“I can tell you.” A new light shone in Anne’s eyes and her voice held an unaccustomed ring, a note of hope, mixed with relief. “I read your testimony in the morning paper, Doctor Curtis, as given at the inquest. You said that Uncle John lay partly on his right side, his hands outflung, and his head resting against the banisters which circle this part of the corridor.”

As she spoke she left the head of the stairs and walked to the spot where Meredith’s body had lain, the others trooping after her.

“Suppose,” she began, addressing Inspector Mitchell who was watching her with eager attention, “suppose Uncle John carried the weapon—shall we say a knife,” her voice faltered, then recovering herself, she spoke with more composure, “carried the knife down this corridor with him, what could have become of it?”

“Blessed if I know,” muttered Mitchell. “We have searched every available spot. There are no cracks and crannies or corners in this corridor which we have overlooked, and have found absolutely no trace of a weapon of any kind. Come, Miss Meredith, did some one,” his voice grew harsh, “carry away the weapon before we got here?”

“No.”

Mitchell turned an angry red as he faced her. He was sensitive to ridicule, and the conviction was growing upon him that Anne was poking fun at him.

“Quit kidding us!” he exclaimed, roughly. “And answer your own question, if you can. If Meredith did carry a weapon in his hand, what became of it?”

“The most natural thing in the world happened to it,” she replied, and this time her note of triumph was plainly discernible in her voice. “As Uncle John fell forward, the knife could have slipped from his outflung hand and fallen through the banisters to the hall beneath. Look—” and she leaned far over the railing.

With one accord the men with her followed her example, even Curtis, in the excitement of the moment, forgetting his blindness as he bent forward and hung over the railing.

The wide circular staircase, with its railing of solid mahogany, was colonial in design. It started from the square hall beneath and, the treads being of unusual width, required a larger “well” than was customary. The banisters did not stop at the stairhead, but circled the “well,” thus protecting the bedroom floor, and allowing a general view of the entrance hall and the front door.

Commencing from the base of the staircase in the entrance hall were boxes of hothouse plants which ran almost to the library door. John Meredith had liked the green foliage against the white wainscoting and, the previous winter, had the boxes put there in place of the cushioned benches which had occupied the space formerly.

“That’s a good theory of yours, Miss Meredith,” admitted Mitchell. “If the knife did drop between one of these banister posts, it must have lighted in that flowerbox. Let’s see.” He whirled around and hurried down the staircase, McLane hotfoot after him.

Anne started forward, then stopped. The next instant a small hand was slipped into Curtis’ as he turned to follow the others.

“Come this way,” she said softly. A pretty color dyed her white cheeks as she saw his face light up. His expression altered quickly to one of concern as his grasp tightened over her icy fingers.

“Are you having a chill?” he asked, halting abruptly.

“Oh, no. It is nerves.” Her smile was a bit piteous. “I will be all right. Please don’t worry. I wonder—I—” She checked her incoherent ejaculations as they went down the staircase and stopped by McLane’s side.

Regardless of the danger of injuring the costly ferns and other plants which filled the boxes, Mitchell and McLane ran their hands among them, feeling with feverish haste among the leaves and the moss which formed a dense covering. Rapidly the two men worked their way down the boxes. A short, excited cry from Inspector Mitchell, who had made more speed than either McLane or Curtis, brought the others to his side. Withdrawing his hand from a box completely filled with ferns, he held up a small, discolored knife.

“Found!” he shouted. “Don’t touch it, doctor.” He laid the knife, which he held gingerly between two fingers, in a clean handkerchief, and extended it so that McLane could get a good look at it. “Those are bloodstains.”

“Probably.” McLane bent closer. “A chemical test will be necessary though, Mitchell, to distinguish bloodstains, rust, and fingerprints.”

“Sure. Hold it a moment, doctor, in the handkerchief, but don’t let it get out of your possession.” Mitchell thrust the handkerchief into McLane’s eager hand, and rushing back to the pantry, appeared a second later with Detective Sergeant Brown at his back, and hastened up the staircase.

“Describe the knife, Leonard,” directed Curtis, as McLane stepped closer to his side.

McLane did not reply at once. Anne, who stood watching the two men with eager eyes, was about to speak when McLane broke the pause.

“A curious weapon,” he said slowly, “but a most effective one, Dave. It is a scalpel.”

“A scalpel,” repeated Curtis.

“Yes, one manufactured by Meinicke.” McLane lowered his hand. “Where do you suppose John Meredith obtained a surgical knife?”

Curtis’ face was alight with interest. “A surgical knife,” he muttered. “Strange!” He paused, then spoke more quickly. “However, the fingerprints will tell us—”

“Of murder,” broke in Mitchell’s harsh voice behind them and they wheeled about. “Miss Meredith,” his eyes never left the young girl’s face, “you have led us to the weapon and thereby proved conclusively that your uncle did not commit suicide. It is a case of cold-blooded murder.”

“Explain your meaning,” directed Curtis, before either of his startled companions could speak.

Mitchell stepped back a few paces. “Look up there,” he pointed, as he spoke, to the next floor where Detective Sergeant Brown stood leaning over the railing gazing down at them. “The sergeant is standing exactly where John Meredith’s dead body was found by Doctor Curtis. Now,” he spoke with significant impressiveness, “if John Meredith carried that surgical knife, as you cleverly suggested, Miss Meredith, and it dropped out of his hand and fell between the posts of the banisters it would have alighted in that box of ferns,” indicating one further down the hall. “By no freak of chance or possibility could it have fallen from there into the box where I found it.”

Anne gazed dazedly at the Inspector. “I don’t understand,” she faltered. “You found the knife—”

“In the wrong place to establish your theory—of suicide.” Mitchell’s covert smile was ominous, and Anne shivered involuntarily.

“One moment.” Curtis changed his cane from one hand to the other, and stepped closer to the Inspector. “Mitchell, suppose you have the sergeant drop a penknife or ordinary knife through the banisters.”

Mitchell looked at him keenly. “You mean—?”

“To reenact the scene of Sunday night, or rather Monday morning,” replied Curtis. “Tell the sergeant to stagger and fall. As he does so we will see if the knife flies out of his hand, and through the banisters, and thus know,” his voice deepened, “exactly where it falls.”

“A capital idea!” declared McLane. “Go to it, Mitchell. I’ll stay here and you watch the proceedings from above. Wait, though,” as Mitchell started for the staircase. “To make the test as complete as possible I’ll give you a scalpel from my surgical bag. It’s here with my hat. First, however, take this,” and he handed the handkerchief and the discolored scalpel, which Mitchell had found concealed among the ferns, back to the Inspector.

As McLane took another scalpel from his surgical kit, Gerald Armstrong ran down the staircase and joined Anne. He was followed more leisurely by Lucille Hull. She shuddered slightly as Mitchell displayed the discolored scalpel before wrapping it securely in his handkerchief and placing it in his pocket. To Anne the minutes seemed endless as she waited for Mitchell to mount the staircase and instruct Detective Sergeant Brown in the role he was to assume.

“What is going on?” demanded Armstrong. He made no attempt to modify his naturally strident voice and it grated on Anne. McLane caught her sudden start, and guessing the strain she was under, explained the situation in a few words. Lucille listened with close attention, her eyes following the movements of the two men on the floor above as far as she could see them.

“Watch out, down below,” called Mitchell. “Stand back a little further, Doctor Curtis; you are too near.”

Curtis retreated a few steps. Anne put out her hand to guide him but dropped it hurriedly on catching her cousin’s gaze; there was a mocking gleam in Lucille’s eyes which brought the hot color to Anne’s pale cheeks with a rush. It had not faded when the silence was broken by the sound of a heavy fall.

A piece of glittering steel came flying through the air. It fell without sound among the ferns and was lost to sight.

Leonard McLane was the first to speak. He waited until Mitchell and Sergeant Brown reached them.

“You were right, Mitchell,” he said, addressing the Inspector. “The scalpel fell directly into this box,” laying his hand upon it. “It is the fourth box from the one where you found the discolored scalpel.”

“Then our theory is correct,” declared Mitchell. He bowed gravely to Anne. “Thank you, Miss Meredith.”

Before she could reply Herman appeared from the pantry.

“You are wanted on the telephone, Doctor Curtis,” he announced. “This way, sir,” and in silence Curtis accepted the butler’s guidance.

A second more and the little group in the square reception hall broke up; Anne accompanying her cousin to her bedroom, and Armstrong, at a quiet word from Inspector Mitchell, led the way into the library, followed by the two police officials.

Left to himself Leonard McLane repacked his surgical kit and took up his hat and overcoat; then he paused before opening the front door and stood in thought. Fully two minutes passed before he moved. Replacing his hat, overcoat and bag on the hall table he turned around and went slowly upstairs, and entered David Curtis’ bedroom. Except for himself the bedroom was empty.

McLane walked directly over to the bedstead and halted by it. Bending down he closely scanned the spotless linen. It was unwrinkled, immaculate.

McLane straightened up with a jerk; his eyes wide with wonder.

“I’ll be—!” he gasped. “The counterpane has been changed.”