"You see? Brains are all right, he says, but the white race needs new bodies. If he isn't suggesting brain substitution, what is he suggesting? Though I confess I never thought of your story until your name was sent in to me a while ago. For the world thinks of Barter as having been killed by the great apes." "Yes, I told newspaper reporters that. I thought it was true. But this Mind Master must be Barter. There couldn't be two persons in the world with mental quirks so much alike." "Tell me what Barter looks like. Oh, there are plenty of pictures extant of the famous Professor Caleb Barter who disappeared from the world some years ago, but he'll know that, of course, and he won't look like the pictures. "Alteration of his own features should be easy for a man who juggles brains." "He may have changed his features since I saw him, too," said Bentley. "But I'm sure I'd know him." Tyler's telephone rang stridently. He took down the receiver. His mouth fell slackly open as his eyes lifted to Bentley's face. But he recovered himself and slapped his hand over the transmitter. "Anybody know you came here?" asked Tyler. Bentley shook his head. "Well," went on Tyler, "I don't know how it happens, but this telephone message is for you!" Bentley's heart seemed to jump into his throat. One of those hunches which sometimes were so valuable to him had struck him, as though it were a blow between the eyes. His lips tightened. His face was pale, but there was a grim light in his eyes. He hesitated for a second, the receiver in his hand, his mouth against the transmitter. "Well, Professor Barter?" he said conversationally. - - - There came a gasp from Thomas Tyler. He jumped to the door and motioned to someone. A man in uniform came to his side. Bentley distinctly heard Tyler tell the man to have this telephone call traced. From the receiver came a well-remembered chuckle. "So you were expecting me, eh, Bentley? You never really believed that one of my genius would fall such easy prey to the great apes did you?" "Of course not, Professor," said Bentley soothingly. "It would be an insult to your vivid mentality." "_Vivid_ mentality! _Vivid_ mentality! Why, Bentley, there isn't another brain in the world to compare with mine. And you of all people should know it. The whole world will know it before I'm finished, for I have made tremendous strides since you helped me to perform that crowning achievement in Africa. By the way, tell your friend Tyler, who just called the officer to the door, that it's useless to try to trace this call!" Bentley jumped as though he had been stung. How had Barter known what Tyler was doing? How had he guessed what Tyler had told the man in uniform? How had Barter known Bentley was visiting Tyler? How had he discovered even that Bentley was back in the United States? Why, besides, was he so friendly with Bentley now?