He gave an evil chuckle and walked to the far side of the cave and opened a secret panel. He drew from a recess a flask and carefully emptied a portion of the contents of the syringe into it. He replaced the flask and closed the panel, and with another chuckle he limped over to a chair and threw himself down in it. For an hour he sat motionless and Dr. Bird carefully worked his way back along the branch and climbed the rope and started for the hollow. * * * * * A faint whirring noise attracted his attention, and he could see the faintly luminous globe in the distance, rapidly approaching. It came to a stop at the spot where it had previously landed and four men got out. Instead of going toward the cave, they towed the globe, which floated a few inches from the earth, toward the side of the hill farthest from where the doctor stood. Three of them held it, while the fourth went forward and bent over some controls on the ground. A creaking sound came through the night and the men moved forward with the globe. Presently its movement stopped and men reappeared. Again came the creaking sound and the glow faded out as though a screen had been drawn in front of it. The four men walked toward the door of the cave. Dr. Bird dropped flat on the ground and saw them pause a few yards below him on the hill and again work some hidden controls. A glare of light showed for an instant and they disappeared and everything was again quiet. Dr. Bird debated the advisability of returning to the window but decided against it and moved down the face of the hill. Inch by inch he went over the ground, but found nothing. In the darkness he could not locate the door and he made his way around to the back of the hill. The precipice loomed above him and he swept it with his gaze, but he could locate no opening in the darkness and he dared not use a flash-light. As he turned he faced the east and noted with a start of surprise that the sky was getting red. He glanced at his watch and found that Carnes had been gone for nearly three hours. "Great Scott!" he exclaimed in surprise. "Time has gone faster than I realized. He ought to be back at any time now." * * * * * He mounted the highest point of the hill and sent three long flashes, followed in turn by three short and three more long to the south and watched eagerly for an answer. He waited five minutes and repeated the signal, but no answering flashes came from the empty hills. With a grunt which might have meant anything, he turned and made his way toward the opposite side of the hollow where the globe had disappeared. Here he met with more luck. He had marked the location with extreme care and he had not spent over twenty minutes feeling over the ground before his hand encountered a bit of metal. As he pulled on it his eyes sought the side of the hill.