"Now move him under that clock!" One of the guards gave a low exclamation, instantly checked at a cold stare from Norbith. And meanwhile the boy was being placed just below, and a little to one side of the big clock. "Remove the lower half of the clock-case!" It was done in a few seconds. The instrument's pendulum now vibrated freely in the air, its weight swinging almost to the boy's head where he sat. "Move him until I drop my hand," said Norbith. A slight push, and instantly the doctor became aware that the heavy pendulum of the clock, on reaching the outward extremity of its swing, was now gently tapping at the boy's left temple. TAP-TAP-TAP-TAP it went, with the peculiar quickness due to the planet's powerful gravity. "Keep him there until I tell you to move him." The tapping continued. To the doctor, of course, the thing was entirely devoid of pain. It made much the same noise the dentist makes with his mallet, only it went on and on, until perhaps two minutes had passed. "Stop!" Instantly the boy was moved away. The student said nothing; neither did the father. Yet the doctor noticed something which meant volumes to his trained senses. The boy's gaze was no longer clear. Instead, dancing lights appeared wherever he looked; tiny flashes of violet and orange, which shimmered before his pupils even though he closed his lids. "Will you ask your father to tell?" inquired Norbith. "No--damn you!" It was the first thing the boy had said. And it came through set teeth, in a voice which the doctor scarcely knew. "Move him back; a little further this time." The tapping began again. This time the boy's head got more of the force of the swing; the tapping was more like a blow. THUD-THUD-THUD came the sound now; and in a few seconds the boy could see nothing for the shivering flames. He gave a faint groan. "Ready to talk now?" "Damn you--no!" in a voice that shook with pain. "Move him closer!" The thud became a pound. The doctor looked for the skull to give way at any moment; he tried his best to control the subconscious, but the boy's agony was too great. The dancing lights had become a continuous flare; the lad moaned steadily. And then quite without warning, the boy broke down and gave out a terrible shriek. Norbith ordered the guards to move him away from the clock. "Ready now?" he inquired calmly. The boy's answer was a snarl. "No!" "Once more!" The thud-thudding began again, and now it had a sharp sound which the doctor instantly recognized. In a moment the boy was shaking the air with cries of such awful agony that the doctor-- "Stop!" cried the father convulsively, his face streaming with tears. "God--the boy doesn't--know! Don't torture him--like that!" The man with the metal heart said: "Will you tell now?" "Don't do it father!" the boy whispered through palsied lips. But no Capellan heard him. The father was saying to Norbith, "I gave the whole outfit to--"