Purchase one of 1st World Library's Classic Books and help support our free internet library of downloadable eBooks. Visit us online at www.1stWorldLibrary.ORG - - "Boys! B-o-y-s!" There was no response to the imperative summons. Professor Zepplin sat up in his cot, listening intently. Something had awakened him suddenly, but just what he was unable to decide. "Be quiet over there, young men," he admonished, adding in a lower tone, "I'm sure I heard some one moving about."