octave-"he's dead. Oh-oh! my father-my father!" and she tried to break from Mrs. Bolstreath's arms to fling herself on the dead once more. "Lillian darling, don't cry," said Dan, placing his hand on her shoulder. "You have not lost the dearest and best of fathers!" she sobbed violently. "Your loss is my loss," said Halliday in a voice of pain, "but we must be brave, both you and I." He associated himself with her so as to calm her grief. "It's not your fault that your dear father is dead."
"I persuaded him to see Mrs. Brown. And she-she-she-"
"We can't say if this woman is guilty, as yet," said Durwin hastily, "so do not blame yourself, Miss Moon. But did you smell any scent on this Mrs. Brown?" Lillian looked at him vacantly and shook her head. Then she burst once more into hard and painful sobbing, trying again to embrace the dead man. "Don't ask her any questions, sir," said Halliday, in a low voice to Mr. Durwin, "you see she is not in a fit state to reply. Lillian," he raised her up from her knees and gently but firmly detached her arms from the dead. "My darling, your father is past all earthly aid. We can do nothing but avenge him. Go with Mrs. Bolstreath and lie down. We must be firm."
"Firm! Firm! – and father dead!" wailed Lillian. "Oh, what a wretch that Mrs. Brown must be to kill him. Kill her, Dan-oh, make her suffer. My good, kind father, who-who-oh" – she flung herself on Dan's neck-"take me away; take me away!" and her lover promptly carried her to the door. Mrs. Bolstreath, who had been talking hurriedly to Inspector Tenson, came after the pair and took the girl from Dan. "She must lie down and have a sleeping-draught," she said softly. "If the doctor will come-" The doctor was only too glad to come. He was a young man beginning to practise medicine in the neighborhood, and had been hurriedly summoned in default of an older physician. The chance of gaining a new and wealthy patient was too good to lose, so he quickly followed Mrs. Bolstreath as she led the half-unconscious girl up the stairs. Dan closed the door and returned to the Inspector and the official from Scotland Yard. The former was speaking. "Mrs. Bolstreath did not smell any perfume on Mrs. Brown," he was saying, "and ladies are very quick to notice such things. Miss Moon also shook her head."
"I don't think Miss Moon was in a state of mind to understand what you were saying, Mr. Inspector," said Halliday, drily. "However, I am quite sure from my own observation that Mrs. Brown did not use the perfume. I would have noticed it at once, for I spotted it the moment I examined the body."
"So did I," said Durwin once more; "but I thought Sir Charles might have used it. You say he did not, therefore the scent is a clue." "It does not lead to the indictment of Mrs. Brown, however, sir," said Tenson thoughtfully, "since she had no perfume of that sort about her. But she must have killed Sir Charles, for she was the last person who saw him alive."
"She may come forward and exonerate herself," suggested Dan after a pause, "or she may have left her address with Sir Charles."
"I have glanced through the papers on the desk and can find no address," was the Inspector's reply; "yet, if she gave it to him, it would be there." Durwin meditated, then looked up. "As she was the mother of the man in Sir Charles's employment who was drowned," he said in his harsh voice, and now very official in his manner, "in the offices of the company who own the steamers-Sir Charles was a director and chief shareholder, I understand from his secretary, Mr. Penn-will be found the drowned man's address, which will be that of his mother."
"But I can't see what motive Mrs. Brown had to murder Sir Charles," remarked Dan in a puzzled tone. "We'll learn the motive when we find Mrs. Brown," said Tenson, who had made a note of Durwin's suggestion. "Many people think they have grievances against the rich, and we know that the late Sir Charles was a millionaire. He doubtless had enemies-dangerous enemies."
"Dangerous!" The word recalled to Dan what Moon had said at the dinner-table when Lillian had playfully offered him a penny for his thoughts. "Sir Charles at dinner said something about dangerous people."
"What did he say?" asked the Inspector and again opened his note-book. Dan reported the conversation, which was not very satisfactory as Moon had only spoken generally. Tenson noted down the few remarks, but did not appear to think them important. Durwin, however, was struck by what had been said. "Sir Charles asked me here to explain about a certain gang he believed was in existence," he remarked. "What's that, sir?" asked the Inspector alertly. "Did he tell you anything?"
"Of course he didn't. How could he when he was dead when I arrived," retorted Durwin with a frown. "He simply said that he wished to see me in my official capacity about some gang, but gave me no details. Those were to be left until I called here. He preferred to see me here instead of at my office for reasons which he declared he would state when we met in this room."
"Then you think that a gang-"
"Mr. Inspector," interrupted Durwin, stiffly, "I have told you all that was said by the deceased. Whether the gang is dangerous, or what the members do, or where they are, I cannot say. Have you examined those windows?" he asked suddenly, pointing to three French-windows at the side of the room. "Yes," said Tenson promptly, "as soon as I entered the apartment I did so. They are all locked."
"And if they were not, no one would enter there," put in Dan quickly. "Outside is a walled garden, and the wall is very high with broken bottles on top. I suppose, Mr. Durwin, you are thinking that some one may have come in to kill Sir Charles between the time of Mrs. Brown's departure and your coming?"
"Yes," assented the other sharply, "if the perfume is a clue, Mrs. Brown must be innocent. Penn, as we know from the statement of the typewriter girl, was in his room all the time, and the servants have fully accounted for themselves. We examined them all-the Inspector and I did, that is-when you were at the theatre," he waved his hand with a shrug. "Who can say who is guilty?"
"Well," said Tenson, snapping the elastic band round his note-book and putting it into his pocket, "we have the evidence of the fly and of the perfume."
"What do you think about the fly?" asked Dan, staring. "I don't know what to think. It is an artificial fly, exquisitely made and has been gummed on the dead man's neck behind the left ear. The assassin must have placed it there, since a man would scarcely do such a silly thing himself. Why, it was placed there I can't say, any more than I can guess why Sir Charles was murdered, or who murdered him. The affair is a complete mystery, as you must admit." Before the inquest and after the inquest, more people than the three men who had held the discussion in the presence of the dead, admitted that the affair was a mystery. In fact the evidence at the inquest only plunged the matter into deeper gloom. Tenson, acting on Durwin's advice, sought the office of the tramp-steamer company-The Universal Carrier Line-in which the late Sir Charles was chief shareholder and director, to learn without any difficulty the whereabouts of Mrs. Brown, the mother of the drowned man. She proved to be an entirely different person to the woman who had given the name on the fatal night, being lean instead of stout, comparatively young instead of old, and rather handsome in an elderly way in place of being wrinkled and worn with grief. She declared that she had never been near Moon's house on the night of the murder, or on any other night. Mrs. Bolstreath, Lillian, the footman, and Dan all swore that she was not the Mrs. Brown who had sought the interview with Sir Charles. Therefore it was argued by every one that Mrs. Brown, taking a false name and telling a false story, must have come to see Moon with the deliberate intention of murdering him. Search was made for her, but she could not be found. From the moment she passed out of the front door she had vanished, and although a description was published of her appearance, and a reward was offered for her apprehension no one came forward to claim it. Guilty or innocent, she was invisible. Inspector Tenson did not speak at the inquest of the gang about which Sir Charles had intended to converse with Mr. Durwin, as it did not seem to have any bearing on the case. Also, as Durwin suggested, if it had any bearing it was best to keep the matter quiet until more evidence was forthcoming to show that such a gang-whatever its business was-existed. Then the strange episode of the fly was suppressed for the same reason. Privately, Tenson informed Dan that he would not be surprised to learn that there was a gang of murderers in existence whose sign-manual was a fly, real or artificial, and instanced another gang, which had been broken up some years previously, who always impressed the figure of a purple fern on their victim. But the whole idea, said Tenson, was so vague that he thought it best to suppress the fact of the artificial fly on the dead man's neck. "If there's anything in it," finished the Inspector, "there's sure to be other murders committed, and