“Oh, we know everything that’s going on,” the goblin grinned; “we get wireless telephone messages from all over the world. Whenever anybody says anything—or thinks anything, even—we learn of it; and if they’re in trouble some one of us good little goblins sets off to help them.” “Why, how good of you!” Bob murmured, in sincere admiration. “You chaps are a bully lot!” “Yes, indeed,” the goblin giggled; “we’re a good-hearted lot—_we_ are. Oh, you’ll just love and worship us when you learn all about us!” And the little green sprite almost choked with some suppressed emotion. “I’m going with you,” the boy said, with sudden decision. “Will your balloon carry two, though?” “We can manage that,” said the goblin. “Come here to the window and take a squint at my aërial vehicle.” [Illustration] Bob crawled to the foot of the bed and peeped out the window. There hung the goblin’s balloon, anchored to the window-sill by means of a rope and hook. The bag looked like a big fat feather bed and the car resembled a large Willow clothes-basket. The boy was surprised, and not a little disappointed. “And you came here in that thing?” he asked, unable to conceal the contempt he felt for the primitive and clumsy-looking contraption. “Of course I did,” Fitz Mee made answer. “And how did you get from the basket to the window here?” “Slid down the anchor-rope.” “Oh!” Bob gave an understanding nod. “And you’re going to climb the rope, when you go?” “Yes; can you climb it?” “Why, I—I _could_ climb it,” Bob replied, slowly shaking his head; “but I’m not going to.” “You’re not?” cried the goblin. “No.” “Why?” “I’m not going to risk my life in any such a balloon as that. It looks like an old feather bed.” “It _is_ a feather bed,” Fitz answered, complacently. “What!” The goblin nodded sagely. “Whee!” the lad whistled. “You don’t mean what you say, do you? You mean it’s a bed tick filled with gas, don’t you?” “I mean just what I say,” Fitz Mee replied, positively. “That balloon bag is a feather bed.” “But a feather bed won’t float in the air,” Bob objected. “Won’t it?” leered the goblin. “No.” “How do you know? Did you ever try one to see?” “N—o.” “Well, one feather, a downy feather, will fly in the air, and carry its own weight and a little more, won’t it?” “Yes,” the lad admitted, wondering what the goblin was driving at. “Then won’t thousands of feathers confined in a bag fly higher and lift more than one feather alone will?” “No,” positively. “Tut—tut!” snapped the goblin. “You don’t know anything of the law of physics, it appears. Won’t a thousand volumes of gas confined in a bag fly higher and lift more than one volume unconfined will?” “Why, of course,” irritably. “Well!”—triumphantly,—“don’t the same law apply to feathers? Say!” “I—I don’t know,” Bob stammered, puzzled but unconvinced. “To be sure it does,” the goblin continued, smoothly. “I know; I’ve tried it. And you can see for yourself that my balloon’s a success.”