CHAPTER VIII.
A SAFE RETURN.
Who could blame Billy if he turned ashy pale at that critical second. He could not believe that this was any scheme of Frank’s for showing off what the great seaplane was capable of, though on previous occasions he had known such a thing to happen.
The one terrible conviction that flashed through his mind was that something had happened to stop their motors at this great altitude; and that the Sea Eagle was now, with ever increasing velocity, heading downward to earth.
If they managed, through any degree of dexterity to escape death, there must always be more or less chance of the machine being wrecked; and even though that catastrophe were avoided, it was sure to fall into the hands of the Germans. Then good-by to their hopes of keeping its construction a secret.
But Frank had been busy meanwhile. He was not the one to be caught napping by any sudden happening. Their present predicament had been accurately discounted by the clever mind that had invented many parts of the strange seaplane.
No sooner did Frank realize that the motive power had ceased than, with a quick snap of the hand, he had turned a valve that was within easy reach.
This allowed pure hydrogen gas from one of the cylinders to rush into the buoyancy devices, which might be called the crowning triumph along the line of insurance against accidents connected with Dr. Perkins’ invention.
As if by magic, the upper wings of the aircraft began to swell until they had all the appearance of puffed-out mattresses. How the eyes of those who were watching down below must have grown round with wonder as they realized that here was something altogether new. It was also a hitherto unheard-of device intended to diminish the terrible risk of a fall ever present with those who go up in aircraft.
The swift volplaning had immediately begun to grow less pronounced, and Billy, feeling that after all they were not going to drop to the ground, drew in his first breath since the accident had come about.
Frank was already busily engaged in examining the stalled motors. So reliable had the same brand always proven in connection with the Sea Eagle type of hydro-aëroplane, that Frank could not remember ever having such an accident occur.