"Huh! Sky train! Sounds foolish to me, but go on!"

"Well, it isn't quite as foolish as it may sound," Tom said, trying to keep his temper. "As you probably have heard, there is to be held, shortly, on the Pacific coast one of the biggest air meets in history. I have sent some exhibits out there and I am planning to send another, my big dirigible, Sliver Cloud. All those are perfected inventions -- they all work -- and so does my experimental sky trainÖ"

"In brief, my sky train will consist of a powerful airplane, of a cabin typer, capable of carrying say a score of passengers," Tom said. "If this was all there was to it I wouldn't be troubling you. But while planes carrying passengers from coast to coast are not uncommon, my plan of attaching to the towing plane a number of smaller planes, without motors, which are called gliders, is new. And my plan of having the towing plane pick up gliders, filled with passengers, at various flying fields between here and the coast, and taking them along, dropping them off as a railroad train drops off coaches at local points, is also new."

"Do you mean to say," burst out the bank president, "that you propose to fly a train of gliders through the air, starting here in the east, pick up other gliders at intermediate points, dropping off some, picking up others and like that?"

"That's exactly what I propose to do," said Tom, smiling.

"It can't be done!"

"Excuse me, but it has been done," Tom said. "I have just come from a test of my new invention. You realize, Mr. William, that it is comparatively easy for a towing plane to start from the ground, towing motorless gliders -- any reasonable number of them. But by my plan, the last glider in the train can be cut loose at any determined point, and will go down to the ground say at Chicago, Denver, or any place between here and the Pacific coast."

"You mean you just cut loose those gliders filled with passengers and let the drop?" asked Mr. William. "That's foolishness! Dangerous! They'll all be killed."

"No," went on Tom. "The Gliders will land as gently as any regular airplane. Each glider will be in charge of a competent pilot who will ease it down to earth. But that is only of my plan. I want to make my coast to coast sky train a sort of express, without stops. And I plan to have it pick up loaded gliders at certain points and pull them out to the coast."

"You mean you're going to dip down in that big airplane of yours, with a string of gliders for a tail, like a kite, and hook on to some other glider, or gliders, waiting on the ground? That can't be done! There would be a grand smash! You needn't think I'll lend you money on such a wild scheme!"

"You don't quite understand," Tom went on, patiently. "I don't propose to pick up gliders from the ground with my sky train. The glider, or gliders, at intermediate points, filled with passengers, will be hauled into the air by an auxiliary motored plane at each landing field, and will be coupled to the rear of my sky train while it is in full flight."

Ö"Let me see if I get you, he said to Tom. "You propose to start a sky train, consisting first, of a big motored air[plane, say from New York, and head for San Francisco. Towed by the big plane will be several gliders, carrying passengers. One glider will have in it passengers who, we'll say, want to land at Chicago. When your sky train gets there, you'll drop off the last glider. Is that it?"

"I won't exactly drop it off," Tom said with a smile. "I will simply uncouple it, as a brakeman would uncouple a railroad coach from the rear of a train. The glider, guided by a pilot, will make the landing safely. At the same time an auxiliary-motored plane on the Chicago field will soar aloft, towing a glider of passengers who want to go to San Francisco. The glider will be coupled to the rear of my sky train in place of the one lef off over Chicago, and the plane that brought it up will circle back to the field."

"Well, I can understand the principle of the thing," grudgingly admitted the bank president. "It sounds all right in theory and I'll admit that we're getting to be quite an air-minded country. But will your plan work and will it pay?"

"It will work," said Tom, with more confidence than he felt since the accident. "And I'm sure it will pay. There is a growing demand for rapid transportation between here and the Pacific Coast,"

"Yes, I admit that. But a sky train! All nonsense, I should say!"

Ö

"Yes. You know, up to now, and before, the tail glider could be released by either the pilot in it or by me, or some one else in the hauling plane. That is, after a signal was given. But this was the weak spot in my invention. You see, I, or someone in the plane, might forget to give the signal, and cur the glider loose, or the pilot in the glider might do the same thing. But with dual double control it isn't possible."

"Why not?"

"For the same reason you can't open your bank safe deposit box all by yourself. A clerk from the bank has to turn half the lock with his key, and you, or he, has to turn the other half with your key. You can't get in with your key alone and the bank clerk can't get in with his key alone. It means dual double control and makes for safety."

"Now if I can change this magnetic coupler a bit, no glider can get loose from my sky train until the pilot in the glider and the pilot, or some responsible party in the same plane, act in concert. That will end all accidents, I think."

Ö

The descent of the sky train glider was the signal for the plane on the ground to start upward with its glider in tow. Getting off to a good fine start in the wind, the small plane rapidly gained height and speed until it was flying after the Eagle that now had but one glider in its "tail."

"The idea," Tom explained to Ned, "is for the lifting plane to come after us, and a little above, regulating her speed until she is flying evenly with us, keeping her glider on a level with our rear one. Then she gradually goes a bit faster until the nose of the raised glider couples to the tail of the other glider. As soon as contact is made the plane cuts loose, zooms up and goes back to the ground."

Ö