He looked at van Heerden thoughtfully, then picked up the phial again. It bore the label of a well-known firm of wholesale chemists, and the seal had apparently been broken for the first time when van Heerden opened the tiny bottle. "You have sent for the police?" Beale asked the agitated manager. "Oui, m'sieur--directly. They come now, I think." He walked to the vestibule to meet three men in plain clothes who had just come through the swing-doors. There was something about van Heerden's attitude which struck Beale as strange. He was standing in the exact spot he had stood when the detective had addressed him. It seemed as if something rooted him to the spot. He did not move even when the ambulance men were lifting the body nor when the police were taking particulars of the circumstances of the death. And Beale, escorting the shaken girl up the broad staircase to a room where she could rest and recover, looked back over his shoulder and saw him still standing, his head bent, his fingers smoothing his beard. "It was dreadful, dreadful," said the girl with a shiver. "I have never seen anybody--die. It was awful." Beale nodded. His thoughts were set on the doctor. Why had he stood so motionless? He was not the kind of man to be shocked by so normal a phenomenon as death. He was a doctor and such sights were common to him. What was the reason for this strange paralysis which kept him chained to the spot even after the body had been removed? The girl was talking, but he did not hear her. He knew instinctively that in van Heerden's curious attitude was a solution of Predeaux's death. "Excuse me a moment," he said. He passed with rapid strides from the room, down the broad stairway and into the palm-court. Van Heerden had gone. The explanation flashed upon him and he hurried to the spot where the doctor had stood. On the tessellated floor was a little patch no bigger than a saucer which had been recently washed. He beckoned the manager. "Who has been cleaning this tile?" he asked. The manager shrugged his shoulders. "It was the doctor, sare--so eccentric! He call for a glass of water and he dip his handkerchief in and then lift up his foot and with rapidity incredible he wash the floor with his handkerchief!" "Fool!" snapped Beale. "Oh, hopeless fool!" "Sare!" said the startled manager. "It's all right, M'sieur Barri," smiled Beale ruefully. "I was addressing myself--oh, what a fool I've been!" He went down on his knees and examined the floor. "I want this tile, don't let anybody touch it," he said. Of course, van Heerden had stood because under his foot he had crushed the digitalis tablet he had taken from the phial, and for which he had substituted something more deadly. Had he moved, the powdered tablet would have been seen. It was simple--horribly simple. He walked slowly back to where he had left Oliva.