Other arrests were made, Rupprecht's maid reported that three troopers belonging to the regiment in garrison had called on her master the very day of the murder; one of them owed him money which he could not pay, and the others, it was thought, had joined him in trying to intimidate the usurer. But the case of these troopers, men who could handle the very weapon that did the deed, broke down on clear proof that they were elsewhere at the time of the murder. The one flaw in the otherwise acute investigation was that the sabres of all the troopers had not been examined before so much noise had been made about the murder. But from the first attention had been concentrated on axes, wielded by woodcutters, and the probable use of a sabre had been overlooked. After the troopers, two other callers had come, and Rupprecht had given them a secret interview. One proved to be the regimental master-tailor, who was seeking a loan and had brought with him a witness to the transaction. Their innocence also was clearly proved; and although many other persons were arrested they were in all cases discharged. [Illustration: "HER BODY ... WAS FOUND IN THE WATER" (p. 40).] The murder of this Rupprecht has remained a mystery. The only plausible suggestion was that he had been murdered by some aggrieved person, some would-be borrower whom he had rejected, or some debtor who could not pay and thought this the simplest way of clearing his obligation. The authorities could not fix this on anyone, for Rupprecht made no record of his transactions; he could neither read nor write, and kept all his accounts "in his head." Only on rare occasions did he call in a confidential friend to look through his papers when there was question of arranging them or finding a note of hand. No one but Rupprecht himself could have afforded the proper clue; and, as it was, he had led the police in the wrong direction. Numerous murder mysteries have been contributed by American criminal records. Special interest attaches to the case of Mary Rogers, "the pretty cigar seller" of New York, who was done to death by persons unknown in 1840, because it formed the basis of Edgar Allan Poe's famous story, "The Mystery of Marie Roget." The scene of that story is Paris, but the murder was actually committed near New York. Mary Rogers had many admirers, but her character was good, her conduct seemingly irreproachable. She was supposed to have spent her last Sunday with friends, but was seen with a single companion late that afternoon at a little restaurant near Hoboken. As she never returned home her disappearance caused much excitement, but at length her body, much maltreated, was found in the water near Sybil's Cave, Hoboken. Many arrests were made, but the crime was never brought home to anyone.