"These thoughts came to the mind of our reporter with lightning rapidity. Mrs. Middlemore had opened the street door, had closed it again, and was now ascending the stairs. What should he do with the dagger? "To retain it would be an unwarranted act, and might be construed into a theft. To take Mrs. Middlemore into his confidence might thwart his operations in the future. He put his hand behind the sideboard, and let the dagger fall. It was now safely hidden from sight, and its presence behind the sideboard could only be discovered, by any other person than himself, by the shifting of that piece of furniture. "Mrs. Middlemore re-entered the room. "'It was a runaway knock,' she said, 'The boys and girls take a pleasure in it. If I could ketch one of 'em I'd bang their head agin the wall.' "'Did you see no one at all?' asked our reporter. "'Only some people staring up at the winders,' replied Mrs. Middlemore. 'The 'ouse 'as become a regular show since that dreadful night. What do they expect to see?' "'Perhaps the ghost of M. Felix,' suggested our reporter, with, it must be confessed, a rather feeble attempt at humor. "'Don't mention sech a thing, sir,' said Mrs. Middlemore, piteously. 'It makes my flesh creep.' "'I only said it in joke; there are no such things as ghosts and spirits.' "'Some people believe otherwise sir.' "'The more fools they. Well, Mrs. Middlemore, there is nothing more I wish to ask you just now; I must get back to my duties. But I must not waste your time for nothing.' "He pressed into her willing palm another half-sovereign, making the second he had given her. "'I'm sure you're very kind, sir,' said Mrs. Middlemore, after furtively glancing at the coin, to see that it was not a sixpence. 'Shall I see you agin?' "'Yes. Good-night, Mrs. Middlemore.' "'Good-night, sir,' she responded, as they went down-stairs. 'I 'ope Sophy won't be gone long.' "'She'll be back soon, I daresay.' He paused in the passage. 'Mrs. Middlemore, are you satisfied that I am your friend?' "'Yes, sir, I am.' "'Then, if anything new occurs, you will let me know at once.' "'I will, sir.' "'And if it should happen,' said our reporter, 'that you remember anything you have forgotten to tell me, you will come and let me know it?' "'I'll be sure to, sir.' "Wishing her good-night again, he left the house, and heard her close the street door behind him with a bang. "It was not without a motive that our reporter had addressed his last words to her. He had an idea that she had not been quite frank with him respecting M. Felix's visitors feeling assured that she could not be so entirely in the dark regarding them as she professed to be. His visit had not been fruitless; he had become acquainted with the loss of the desk, and he had discovered the dagger with its curiously shaped handle. Two steps advanced in the mystery, which might lead to something of importance.