Never did paper look so dazzlingly white, or letters so intensely black, before Mr. Longcluse's eyes, as those of this ominous letter. He crumpled it up, and thrust it in his trousers pocket, and gave to the position a few seconds of intense thought. His first thought was, what a fool he was for not having driven Davies to the wall, and settled the matter with the high hand of the law at once. His next, what could bring him to Paris? He was there for something. To see possibly the family of Lebas, and collect and dovetail pieces of evidence, after his detective practice, a process which would be sure to conduct him to the Baron Vanboeren! Was this story of the boot and the tracing of the bloodstained foot-print true? Had this scoundrel reserved the strongest part of his case for this new extortion? Was his trouble to be never ending? If this accursed ferret were once to get into his warren, what power could unearth him, till the mischief was done? His eye caught again the words, on which, in the expressive phrase which Mr. Davies would have used, his "sight spred" as he held the letter before his eyes--"Mister Loncluse, i do not want to have your life." He ground his teeth, shook his fist in the air, and stamped on the floor with fury, at the thought that a brutal detective, not able to spell two words, and trained for such game as London thieves and burglars, should dare to hold such language to a man of thought and skill, altogether so masterly as he! That he should be outwitted by that clumsy scoundrel! Well, it was now to begin all over again. It should all go right this time. He thought again for a moment, and then sat down and wrote, commencing with the date and address-- "PAUL DAVIES, "I have just received your note, which states that you have succeeded in obtaining some additional information, which you think may lead to the conviction of the murderer of M. Lebas, in the Saloon Tavern. I shall be most happy to pay handsomely any expense of any kind you may be put to in that matter. It is, indeed, no more than I had already undertaken. I am glad to learn that you have also written on the subject to Mr. David Arden, who feels entirely with me. I shall take an early opportunity of seeing him. Persist in your laudable exertions, and I shall not shrink from rewarding you handsomely. "Yours, "WALTER LONGCLUSE." He addressed the letter carefully, and went himself and put it in the post-office. By this time Sir Richard Arden was awaiting him at home in his drawing-room, and as he walked homeward, under the lamps, in inward pain, one might have moralised with Peter Pindar-- "These fleas have other fleas to bite 'em And so on _ad infinitum_." The secret tyrant had in his turn found a secret tyrant, not less cruel perhaps, but more ignoble. "You made your visit?" asked Mr. Longcluse. "Yes." "Anything to report?" "Absolutely nothing." A silence followed.