Entering Tom Swift’s private laboratory from a room farther down the hall, Ned Newton, who seemed somewhat out of breath, glanced at the young inventor and asked: “Do you seem to be getting anywhere with it, Tom?” For a moment there was no reply. Tom, who had been leaning over a complicated apparatus of wires, switches, and radio bulbs that glowed dimly, was slowly turning a dial. Ned repeated his question, adding: “What seems to be the trouble?” “Trouble?” queried Tom, looking at Ned with eyes, however, that did not see him. “There must be some trouble,” insisted Ned, “or you’d have been capering around here on one leg when I came in after doing my stuff back there,” and he nodded toward the room farther down the hall. “How about it?” Tom Swift glanced away from the apparatus, which very much resembled a radio receiving set, to a yard-square burnished sheet of metal hanging in front of him and connected to the other mechanism by several wires. This burnished sheet appeared to be made of a mirror of some metal with a square of heavy plate glass covering it. “Can’t you answer?” inquired Ned, with a chuckle. “Boy, I certainly did some acting back there all by myself! And I’d like to know whether I got it through to you. Did I? Bet I did that song and dance for the fiftieth time just now. Come on—wake up—did it come through? What’s the matter, anyhow?” “I—I’m thinking,” said Tom slowly. “Don’t need an interpreter to tell me that!” and again Ned chuckled. “I can see it with half an eye. But was it a success?” “Yes, and no,” replied Tom, turning a switch which seemed to cut off some electrical current, for at once a faint hum that had been audible in the laboratory ceased. “Yes, and no. It came through all right; that is, part of it did, but the rest——” Tom ceased speaking and bent over his apparatus. He adjusted some set screws, turned a couple of dials, and changed three of the radio tubes which, now that the power was cut off, no longer glowed with light beneath the quicksilver coatings on the thin glass. “Do you want me to go back there and do it over?” asked Ned. “I’m willing, if you say so,” and he started for the room he had just left—a room wherein, under the focused rays of a battery of powerful lights and close to a box containing a strange assortment of tubes and transmitters, Ned had done his “stunt,” which consisted of singing and dancing about on a small stage. He performed alone—there was no audience but the distant one of Tom Swift in his laboratory several hundred feet away.