Captain Bradford and Jerry Hall are about to begin the test flight, which they hope will lay the foundation for their ultimate escape. Then, following the escape, Captain Bradford's formula will be used to gain possession of the Magic Island and force the Euclidians to give up their mad scheme of world terrorism. Down in the strange underwater city of Euclidia, 400 feet below the surface of the ocean, Jerry and the captain are standing in the immense rocket ship chamber, examining one of the thousand mile an hour planes, which is also a submarine. Keops, the master builder of Euclidia, explains something of the weird plane's action. As they wait for Thales, the Euclidean electrical expert, Thales will accompany them on their first ride in the rocket ship. I sure wish that fellow Thales would hurry up and get here. I'd like to take a ride in this thing. Are you going along, Keops? Naturally. As the master builder of Euclidia, my place is with this rocket plane while it is being tested. Thales is responsible for the electrical impulses used. G-47 for the mechanics of the whole. And mine is the responsibility for the construction of the plane. Well, the captain's going to try and find out what's wrong with these things. Well, not exactly that, Jerry. G-47 merely asked me to make some test runs in these ships and see if I could discover any weakness in them. All of which is most ridiculous. If the Euclidians can find no flaw in their work, how can you, a mere engineer in your world, hope to discover what we of Euclidia's great scientific fountainhead have overlooked? Oh, you think Tex isn't as smart as you are, huh? Steady, Jerry. Have no fear, Captain. Nothing this prattling young fool could say would make me angry. It merely annoys me. Okay, I'll keep still. Might be just as well. All right, I won't say anything more about it. But I can go right on thinking the captain's smarter than you are. You'll well confine yourself to thinking at once. Is the rocket plane prepared? How do you do, Thales? The plane is prepared for 500 miles. One half hour of flying. So G-47 puts little trust in our dear captain? Obviously. The orders are to remain within 100 miles of Euclidia, conducting our experiments while circling at altitudes not to exceed 50,000 feet. Excellent. That will make it rather difficult for you to attempt any trickery, Captain. Decidedly so. Hmm. We're not to exceed 50,000 feet in altitude. Correct. But we could exceed that. I mean, these planes will fly at altitudes greater than 50,000 feet. Naturally. These rocket planes cannot attain their maximum speed until they reach the rarefied atmosphere above 50,000 feet. Golly whiskers. What did you say? Oh, nothing. That is probably true. Well, gentlemen, if you've amused yourselves sufficiently at our expense, I suggest we get along with this cruise. Agreed. Thales, will you enter your compartment? I will. Bradford and Hall will sit behind me in the gas chamber. You, K-ops, will occupy the stern section. I want to see everything that goes on. Can I watch it all from here? Easily. Though these interiors give the impression of considerable size, most of that is used for fuel storage and instruments. Well, I'd say there was a big weakness there. You can't carry much of a payload in one of these things. That is indeed worthy of consideration. But perhaps you forget the cruising radius. Yeah. You don't have to carry very much when you can travel 1,000 miles an hour for 10,000 miles. That's true enough, son. Well, are we all set? I am ready. Ready here. You may all relax in your compartments. There is no appreciable sensation involved. What's going on now? We are now moving down an incline into the lock. Must be plenty of pressure on that lock at this depth. As we enter the lock, it will be closed about us and raised within five fathoms of the surface. At that point, the pressures within the lock and without will be equalized, and our rocket plane will slip out into the water. The rocket plane acts as well as a submarine as it does as an airship? Yes, though at moderate speeds. Something slow like 50 or 75 miles an hour underwater, huh? Precisely. That's plenty fast for us. The lock is now being filled with water. In a few seconds, we will be on our way to the surface. Is it all right if I ask a question? Anything within reason will be answered. Well, this is a mighty good question, I think. How does this lock get up to the surface with us? You just beat me to it, Jerry. I was going to ask that. The process is quite obvious. The lock is now full. The walls of this lock are air chambers. These will carry us to the desired depth. But how does it work after we get up there? I will open this visibility slide. You may then see the operator in the lock. Gee, look, Tex. There's a fellow in the corner of the lock with a lot of instruments and gadgets around him. Yep, we're going up. I suppose it's all very simple to you, but I don't understand half I see around here. How does the lock get back down here again after we leave it? That is very simple, Captain Bradford. The air chambers are flooded and the lock sinks slowly. How do you control the return to the landing ramp we've just left? The giant Euclidean magnets will pull the lock back into position and these locks may be used at any of the ramps as their only contact with the ramp is electrical. Boy, this is sure something, isn't it, Tex? It sure is, Jerry. What would the folks back home think of this one? We will now leave the lock. In a few seconds, we will proceed under our own power. Well, let's not waste much time using this thing as a submarine. I want to see how it works as an airship. I'm a little impatient for that myself, kid. We are now free of the lock. Gee, can we go up to the surface now? One moment. It is necessary to observe the surface of the water for a considerable distance. Might be a good idea to make sure no one is watching us at that. I am now using the prism reflectors. The surface is clear of all shipping within a radius of 100 miles. You can see 100 miles in all directions with that thing? Naturally not. Then how does it work? On the principle of the electric eye. This instrument transmits a constant beam in all directions. It has an effective range of 100 miles. If the beam is not interrupted, there is no magnetic or metallic body within that range. Hey, but how about Euclidia? We're not more than a few hundred feet from that place. It's got magnets all over it. This beam is refracted along the surface of the water only. We would receive no impulses from a depth of more than three feathers. How about a submarine? The speed of submarines from your world is so ridiculously low and their clumsy shape so easily identified that the main control room on Euclidia would have notified us when such a vessel was within 200 miles. Are you prepared to rise to the surface? I am prepared. Proceed. Gee, now what's happened? We are now lying on the surface of the water. Did you close that visibility slide? I can't see a thing. Did you think we would burst out of the water for a chance observer to see? I thought you said we were safe. Nothing is left to chance on Euclidia. Well, I still can't figure it out. What is the fact that I can't see anything got to do with our safety? We are surrounded by a ring of magnetic fog. This plane has created its own fog ring instantly? Precisely. I'll say it was precisely. Are you ready for the air fins? Ready. Are the wings going out now? They are. You will be able to see them once we are in the air and there is no further need of the fog ring. The fins are in place. Very well. I will dissolve the fog ring. Gee, Tex, look, the fog's gone. Yes, Jerry, it didn't take long. We are ready for a test flight. I will make such explanations as may be required. Thales, you will navigate. Right. We rise. Oh, boy, we're flying. What's our speed, Keops? We are flying at the rate of 500 miles an hour and gaining altitude at the rate of 4,000 feet per minute. 4,000 feet of climb a minute and we can't even feel it. Well, these chairs of ours are on universal joints, just like they were in the regular submarines. Precisely. Now, if you will watch this instrument panel before me, you will note our progress as I increase our speed to 800 miles an hour and our rate of climb to 10,000 feet per minute. 10,000 feet a minute? Observe the instruments. But hey, 10,000 feet a minute, that's pretty near straight up. It might be, Jerry, if our forward speed wasn't so terrific. Precisely, we progress forward 700, 2,000 feet while climbing only 10,000 feet in 60 seconds. Therefore, our actual rate of climb is something less than 15 degrees. Yes, it all sounds very simple when you figure it like that. But what I can understand is how this compressed gas you use for fuel will drive this huge metal contrivance upward at 15 degrees and forward at 800 miles an hour and do it all noiselessly. The gas is very simple. You are quite aware that hydrogen is inflammable and therefore, under proper conditions, also explosive. Sure, we know that. We merely admit the air through tubes in the nose of the plane. This is properly mixed with a free agent which I must decline to reveal to you. And as the gas is released through tubes in the stern, it mixes with natural hydrogen in the air, causing a series of explosions. But golly, we can't hear these explosions. Well, I'm not enough of a lightning calculator to have it all figured out in my head. But it seems to me that we must be traveling at approximately the speed of sound. You mean we're going as fast as sound travels? The captain is correct. Our speed is almost identical with the speed of sound at this temperature and this altitude. However, even if we could remain stationary during the discharge of the gas, you would not be conscious of it as the explosions are continuous and do not disturb the air within this plane. Boy, this is sure some airship. More than that, Jerry. We're taking a trip we can remember for a long time. Silence. What's the matter? Silence. There is a disturbance on the radiograph. I will establish communications with Euclidia. Straight airplane, X1 reporting. Straight airplane, X1 to Euclidia. There is a disturbance on our radiograph. Instructions. Waiting for instructions. What's this labrador mean? It might mean a number of things. Though in all probability, our course has been crossed by another Euclidean craft. The beam to Euclidia is clear? Precisely. That course signal is steady, but this instrument continues to register disturbance. That can mean but one thing. There is another flying machine of some type on our course. And at greater altitude, we will remain at this course. Come what may.
