On the cot at Philo Gubb's side lay a copy of that day's morning Chicago paper, with a two-column spread headline reading, "Wife Offers $5000 Reward," and it was this that had driven Philo Gubb, the paper-hanger detective, to renewed study of Lesson Eleven--"Procedure in Abduction and Missing Men Cases." Mr. Custer Master, of Chicago, had mysteriously disappeared. One paragraph in the article had caught Mr. Gubb's particular attention:-- Mrs. Master feels that her husband is still alive, and insists that Mr. Master will be found in one of the Iowa towns on the Mississippi River. The police of these towns have been notified, and detectives have gone to investigate. The Masters stand high in South-Side society. Mr. Master, it is understood, recently inherited $450,000 from a maternal uncle. At the time the will was probated considerable interest was aroused by the fact that the legacy was to go to Mr. Master only on condition that he carried out certain provisions contained in a sealed envelope, to be read only by the executors and Mr. Master. And so on. The paper pointed out that Mr. Master had been a sufferer from dyspepsia for many years, but this had not had a permanently depressing effect on his mind. His home relations were most satisfactory. His own business--he was a dealer in laundry supplies and laundry machinery--was doing well, and no trace of outside troubles could be discovered. On the morning of his disappearance, Mr. Master had shown some signs of mental eccentricity. A neighbor, happening to be at her window, saw Mr. Master come hurriedly from the door of his house. An hour later a friend passed him as he was standing on a corner six blocks from home. Mr. Master seemed greatly distressed. "I can't do it! It kills me; I can't do it!" he was muttering to himself. "I never could do it. I said so." The next news of Mr. Master was gained from the keeper of a bath-house and swimming-pool known as the Imperial Natatorium. About ten o'clock, Mr. Master entered the Natatorium hurriedly, asked the price of baths, and chose to pay for a plunge in the big swimming-pool. He paid in advance, removed his garments in one of the small dressing-rooms, put on a swimming-suit and went to the edge of the big pool. Here he grasped the rail and extended one foot until his toes touched the cold water, when he uttered a cry, rushed to the dressing-room, and, as soon as he had thrown on his clothes, dashed from the building. That was the last seen of Mr. Master. Philo Gubb, having finished reading Lesson Eleven for the third time, had picked up the Chicago paper when the silence of the Opera House Building was disturbed by the sound of feet ascending the brass-clad stairs.