And here was something upon which, for all he knew, he might learn his first lessons. In the sunk hangar located on the wide upper deck of the airship lay a machine which might well have attracted the attention of some of our expert flyers. For Joe Gresson was no ordinary inventor. As we have endeavoured to convey to the reader, the silent Joe was indeed a genius, a young man thoroughly well trained in the principles of engineering, and gifted with a brain of unusual capacity. Hence his great airship. Hence also this adjunct to it. Dick and his friends looked upon a machine differing only in form and size and engine from those common at the moment. The principle was precisely the same, and yet the perfection of engineering and design incorporated in the machine in question made of it an article of astonishing efficiency. "Same as many others at first sight, but different," observed the Major, while Dick had his head thrust almost into the very heart of the machinery. "Why, there's the Colonel. Well, Steven, what do you think of the vessel which brought us out to Adrianople just in time to snatch you from that extremely uncomfortable city?" There was a glow on the bronzed, if somewhat pinched, face of the one addressed; for, as we have said, Colonel Steven was an enthusiast where modern advancement was in question, while the science and art of the flyer was as attractive to him as to any. "Think, my dear Major!" he observed. "What can one think? One is absolutely and positively astounded. I can now scarcely believe that I am really on the top of an enormous airship, bigger even than a Zeppelin, and suspended some hundreds of feet in the air." "Pardon--thousands, Colonel," said Joe's quiet voice. "Here is the exact reading--ten thousand two hundred and eighty-five feet." He stepped across to one of the posts that supported the rail running round the deck and consulted an instrument affixed to it. "Ten thousand feet! But----" gasped the Colonel, "you'll explode." "Bust, in other words," Dick whispered to Alec. "Call a spade a spade, my boy. That's the worst of getting senior in any service, for you have to choose and pick your words, which is a bit of a nuisance. 'Bust' here is the correct and proper description." "A Zeppelin would," added the Colonel, failing to hear Dick's grinning aside. "Pardon once more: a Zeppelin would be incapable of ascending much above six thousand feet. At least, that is their record so far, and it is for that reason that, though a menace to all nations who have none, supposing Germany were to declare war, and such nations were within the six hundred miles radius, the Zeppelin is still not entirely mistress of the air. There is always the speedy, powerful aeroplane, capable with ease of ascending infinitely higher, far out of range of her deck guns, for Zeppelins carry weapons above just as you see here, and from that point dropping bombs upon her."