"This was enough to revive old memories and set mother to brooding over it. Her health was not very good, and I am sure that she worried herself to death. Before she died she told me of a dream that had come to her for three successive nights. In that dream she had seen my father, and he was still living, although he was unable to return to her. Just why he could not return was not very clear, but it was because of Dugan. "As she was dying, my mother called me to her side and told me of the dream. 'My boy,' she said, 'I know your father is still living, and I want you to find him. Something has told me that you will be successful. Promise me that when I am gone you will not rest until you have found him or have satisfied yourself beyond the shadow of a doubt that he is dead.' "I gave that promise, and I am here to search for my father and for Uric Dugan. If father is not living, I may be able to avenge him, and that will set me at rest. "By accident I was thrown in with Mr. Merriwell, and we became somewhat friendly. I told him my story, and he was intensely interested in it. He asked me to let him go along. I did not refuse, and he said he would obtain your consent. That is all." "Young man," said Professor Scotch, "I sympathize with you, and I sincerely hope you may be successful; but I do not care to have Frank thrust himself into such perils as you may encounter on that search." "Hold on, professor!" cried Frank. "Just wait and----" Scotch waved his hand. "The time has come for me to assert my authority," he said, sternly; "and I propose to assert it." "You will not let me go?" "No, sir!" "All right. You'll be sorry, professor." "That sounds like a threat, young man. Don't threaten me. This search looks like a wild-goose chase. How do you propose to reach this retreat of the Danites?" he asked, turning to Clyde. "By cruising down the river in a strong boat which I have bought and provisioned for the trip." "And did you boys think of going alone?" "Oh no." "Who was going with you?" "Two explorers." "Their names." "Colton Graves and Caleb Kerney." "What do you know about them?" "Nothing, except that they wish to take a cruise through the canyons." "Young man," said the professor, "let me give you a bit of advice." But before he could do so there came a sharp knock on the door. CHAPTER XV. PROFESSOR SEPTEMAS SCUDMORE. The door opened with a quick, jerky movement immediately after the knock, and, without waiting to be invited to enter, a tall, angular, thin-legged, knock-kneed man walked into the room with a peculiar movement that seemed to indicate that his legs were in danger of breaking at every step.