The long corridor through which he had just come was deserted. The narrow entry and stairway appeared to be for the use of servants only, and entirely out of use at that hour. Nevertheless, while still only part way up the stairs, Patsy suddenly heard the rustle of skirts and hurried footsteps in the narrow entry on the third floor. He stopped short and listened. The sounds ceased in a moment, and Patsy thought he heard the cautious closing of a door. Uncertain as to the last, however, he remained motionless on the stairs, holding his breath, and listened intently for several moments. “By Jove, that’s mighty strange,” he said to himself. “I certainly heard a woman’s steps and the rustle of skirts. She was in a hurry, too, yet was moving stealthily. That ought to signify something. Have I stumbled upon a rear entrance to Kate Crandall’s suite? Has she eluded the chief by stealing out of a back door? Gee! I’d better look into this.” Patsy’s suspicion was perfectly natural under the circumstances. It acted upon him like a spur, moreover. He crept quickly up to the third landing and glanced through the narrow hall. It was unoccupied. The several doors were closed. A short side entry around a corner, and several feet from the stairs, caught Patsy’s eye. That also was deserted. It contained only a single door, also closed, and Patsy stole nearer to it and listened. He could hear no sound from within, nor detect any sign of light on the threshold. He stole away, retracing his steps, and listened at one of the other doors, then another and still another. Patsy paused longer at the last, then suddenly crouched and tried vainly to peer through the keyhole. He had heard a man’s voice from within, crying curtly: “Come in!” “Gee! he’s not addressing me,” thought Patsy. “He couldn’t have heard my catlike tread.” Then other words reached his ears, and a familiar voice. “Holy smoke! it’s the chief himself,” he muttered. “He just inquired for Sheldon, or Floyd. He has just arrived in Sheldon’s suite, as sure as I’m a foot high, instead of interviewing Kate Crandall. He already has seen her, mebbe, and----” Patsy’s inference was correct, but his rapid train of thought ended abruptly. He heard a sound from the direction of the stairs. He thought some one was ascending them. “Gee! I must not be caught playing the spy here,” flashed through his mind. “Nor must I lose the chance of doing so later. I’ll hide in the side entry.” He darted toward it on the instant, eager to round the corner before the approaching person could arrive at the head of the stairs--on which Patsy still supposed him to be. He had, however, mistaken the precise direction of the sound. He moved like a flash, yet as noiselessly as a shadow. He turned the corner at nearly top speed and collided violently with another--none other than Mr. Philip Floyd.