“It is very interesting,” she said, with a sigh, and then, suddenly; “Look, Ghek!” and pointed quickly back in the direction of the tower.  The kaldane, still holding her turned half away from her to look in the direction she had indicated and simultaneously, with the quickness of a banth, she struck him with her right fist, backed by every ounce of strength she possessed—­struck the back of the pulpy head just above the collar.  The blow was sufficient to accomplish her design, dislodging the kaldane from its rykor and tumbling it to the ground.  Instantly the grasp upon her wrist relaxed as the body, no longer controlled by the brain of Ghek, stumbled aimlessly about for an instant before it sank to its knees and then rolled over on its back; but Tara of Helium waited not to note the full results of her act.  The instant the fingers loosened upon her wrist she broke away and dashed toward the hills.  Simultaneously a warning whistle broke from Ghek’s lips and in instant response the workers leaped to their feet, one almost in the girl’s path.  She dodged the outstretched arms and was away again toward the hills and freedom, when her foot caught in one of the hoe-like instruments with which the soil had been upturned and which had been left, half imbedded in the ground.  For an instant she ran on, stumbling, in a mad effort to regain her equilibrium, but the upturned furrows caught her feet—­again she stumbled and this time went down, and as she scrambled to rise again a heavy body fell upon her and seized her arms.  A moment later she was surrounded and dragged to her feet and as she looked around she saw Ghek crawling to his prostrate rykor.  A moment later he advanced to her side.

The hideous face, incapable of registering emotion, gave no clue to what was passing in the enormous brain.  Was he nursing thoughts of anger, of hate, of revenge?  Tara of Helium could not guess, nor did she care.  The worst had happened.  She had tried to escape and she had failed.  There would never be another opportunity.

“Come!” said Ghek.  “We will return to the tower.”  The deadly monotone of his voice was unbroken.  It was worse than anger, for it revealed nothing of his intentions.  It but increased her horror of these great brains that were beyond the possibility of human emotions.

And so she was dragged back to her prison in the tower and Ghek took up his vigil again, squatting by the doorway, but now he carried a naked sword in his hand and did not quit his rykor, only to change to another that he had brought to him when the first gave indications of weariness.  The girl sat looking at him.  He had not been unkind to her, but she felt no sense of gratitude, nor, on the other hand, any sense of hatred.  The brains, incapable themselves of any of the finer sentiments, awoke none in her.  She could not feel gratitude, or affection, or hatred of them.  There was only the same unceasing sense of horror in their presence.  She had heard great