"I figured that she'd have the cipher key on her to-night, for it was her first opportunity of passing it along to the man I felt certain she was working for. Sure enough, as she passed him about half an hour ago she tapped her bracelet, apparently absent-mindedly. As soon as he was out of sight I sent one of the maids with a message that some one wanted to see her in one of the smaller rooms. Thinking that it was the ambassador, she came at once. I was planted behind the door, handcuffed her before she knew what I was doing, and then signaled you! "Quite elementary, my dear Melville, quite elementary!" * * * * * "That," added Quinn, "was the last they heard of Mrs. Armitage. Taylor reported the matter at once, but the chief said that as they had the code they better let well enough alone. The following day the woman left Washington, and no one has heard from her since--except for a package that reached Taylor some months later. There was nothing in it except that photograph yonder, and, as Taylor was interested only in his bride, _nee_ Madelaine James, he turned it over to me for my collection." XXIV FIVE INCHES OF DEATH "Quinn," I said one evening when the veteran of the United States Secret Service appeared to be in one of his story-spinning moods, "you've told me of cases that have to do with smuggling and spies, robberies and fingerprints and frauds, but you've never mentioned the one crime that is most common in the annals of police courts and detective bureaus." "Murder?" inquired Quinn, his eyes shifting to the far wall of his library-den. "Precisely. Haven't government detectives ever been instrumental in solving a murder mystery?" "Yes, they've been mixed up in quite a few of them. There was the little matter of the Hallowell case--where the crime and the criminal were connected by a shoelace--and the incident of 'The Red Circle.' But murder, as such, does not properly belong in the province of the government detective. Only when it is accompanied by some breach of the federal laws does it come under the jurisdiction of the men from Washington. Like the Montgomery murder mystery, for example." "Oh yes, the one connected with the postmark that's framed on your wall over there!" I exclaimed. "I'd forgotten about that. Hal Preston handled it, didn't he--the same man responsible for running down 'The Trail of the White Mice'?" "That's the one," said Quinn, and I was glad to see him settle luxuriously back in his old armchair--for that meant that he was preparing to recall the details of an adventure connected with a member of one of the government detective services. * * * * *