Dick started; he recognized one of the three men as Von Kettler. He moved slowly forward, very softly, his feet making no sound on the fiber matting that covered the floor. * * * * * "Did that feel good, American swine?" asked Von Kettler softly, and Dick saw, with horror, a red weal on the old man's forehead. "Now you are perhaps in a more gracious mood, Professor? The unknown isotope in that black gas of yours--you are disposed to give us the chemical formula?" "I'll see you in hell first," raved old Luke Evans, writhing in his chair. Von Kettler turned to the man holding the white-hot metal, and nodded. But at that moment a door behind Evans's chair opened, and Fredegonde Valmy appeared in the entrance. Von Kettler turned hastily, snatched the pliers from the man's hand, and laid the metal in a receptacle. But the girl had seen the action. She looked at the weal on Luke's forehead, and clenched her hands; her eyes dilated with horror. "You have been torturing him, Hugo!" she cried. "Freda, what are you doing in here? Oblige me by withdrawing immediately!" cried Von Kettler. "Where is Captain Rennell?" the girl retorted. "I will know!" "He is upstairs, watching the approaching Yankee fleet, and waiting to see its destruction," returned the other. "You are lying to me! He has been killed, and this old man has been tortured!" cried Fredegonde. "I tell you, Hugo Von Kettler, you are no longer a half-brother of mine! I am through with you!" "Unfortunately," sneered Von Kettler, "it is not possible to dispose of a family relationship so easily." * * * * * "It is cheap to sneer," the girl retorted. "But you sang a very different song when you were in the penitentiary, in terror of death, and you begged me to come and throw you the invisible robe through the bars. You promised me then that you would abandon this mad enterprise and come away with me. You swore it!" "I have sworn allegiance to my Emperor, and that comes first," retorted Von Kettler. "Oblige me by retiring." "I shall do nothing of the sort," cried the girl hysterically. "When you used me as a tool in your enterprises in Washington, you played upon my patriotism for my conquered country. I thought I was undertaking a heroic act. I didn't dream of the villainy, the cold-blooded murder that was to be wrought.