CHAPTER I

Hazardous Flight

Flying a mile high above the rolling hills of the countryside, Terry Mapes suddenly put _Skybird_, her little blue-and-gold monoplane, into a series of loops. She was feeling good, her brown eyes were keenly alive and her slight boyish figure sat erect as she handled the controls of her plane. And being a young and lively girl, she wanted to turn somersaults in the sky to express her joy.

Her twin sister, strapped in the rear cockpit, spoke to her through the earphones, "Quit your circus stunts, Terry, and keep going! We've got a long trip ahead of us."

"You guessed it, Prim. That's why I'm feeling so full of pep!" answered Terry and her voice died away as she put _Skybird_ into another loop among the clouds.

The next minute her plane was on an even keel and Prim repeated: "Terry, _will_ you stop clowning? Save that pep! You'll need it before we get to South America."

"Don't I know it! I'll be good and tired before I reach Peru, but right now I feel like a million dollars. I wouldn't change places with the President of the United States or the Prince of Wales," said Terry with a laugh. "I'm perfectly satisfied to be Terry Mapes, airplane pilot on a secret errand to the wilds of South America."

"And I," interrupted Prim, settling back for a comfortable trip, "would rather be just Prim, the twin sister of the cleverest girl flyer who ever did a barrel roll.--But I wish she'd cut out the stunts for the present!"

Dick Mapes, the father of the girls was an old airmail pilot. He had taught both girls to fly. The home-loving Prim had become a good pilot but she was not as fond of the sport as her sister. Prim was a pretty blonde type, inclined to plumpness, easy-going and gay, while Terry was serious, high strung and nervous, Terry loved to fly and now that her father was crippled from an accident and still unable to leave his wheel chair, she was trusted with many important air jobs.

To Terry it was not half so venturesome to cut up antics in the air as it would have been to race in a motor boat or automobile. She always felt perfectly safe and perfectly happy when she could put a thousand feet of air between her plane and the earth.

Prim, in spite of her protests, had perfect confidence in her twin sister's ability to handle her plane and whether she was stunting or flying straight. Prim could feel sure of a happy landing and enjoy herself.

At last Terry had worked off her excitement. She leveled out her plane and throttled the engine down to a steady cruising speed. Terry's success as a flyer was due to the fact that the girl understood her plane thoroughly and treated it with respect. Apart from an occasional burst of speed to work off her excess energy and a few stunts to keep her in practice, Terry kept her plane on a level keel and never overtaxed it.

Mile after mile sped by below them and Terry's mind was racing ahead to the work she had to do, a mission which might be full of perils and thrilling hazards.

Since the day when her father had started out with such high hopes of success in the venture of The Dick Mapes Flying Field, things had gone all wrong with him. He had obtained an option on a large tract of land at Elmwood from the owner, Peter Langley who lived at a small gold mine in the wilds of Peru, and it was this field that had aroused the envy of his business rival, Joe Arnold.

Most of Dick's misfortunes had come through the jealousy of this unscrupulous flyer. Joe Arnold was anxious to get control of Dick Mapes' field, as it was situated near his own and was at a safe point for carrying on his illegal business. If he could once get this field he would be isolated and not run the risk of being seen when loading and unloading his planes.

Joe Arnold was a dangerous rival. He would stop at nothing to carry out his schemes. And for the last two years he had kept Dick Mapes and his helpers in a state of anxiety. At first there had only been slight inconveniences, mishaps that were annoying, but through his agent, Bud Hyslop, who worked as mechanic for Mapes, Joe was able to learn all the plans of the field. He grew bolder and with Bud to carry out his orders, the field was the scene of frequent accidents.

Suspicion pointed to Bud after the crash in which Dick Mapes was injured. Dick was a careful pilot and always checked up on his plane before starting out on a trip. Yet as soon as he was in the air that day, he found that someone had been tampering with his plane. It was too late to save himself. The plane crashed from a height of five hundred feet. It was a miracle that saved Dick from death.

Allan Graham, his young partner, declared that he had seen Bud near the plane just before Dick took off. But no one could say for sure that Bud Hyslop was guilty, although most of the people on the field believed he was. Dick was too tender-hearted to discharge the boy without a reason and it was only after Bud had proven beyond doubt that he was working against the field that Dick let him go.

One thing after another had happened to discredit Dick and for a time it looked as if he might have to give up the field entirely.

And as a final blow word had come from Peter Langley saying that he did not care to extend the option, after he had let it be understood that he would do so. Dick felt as if the struggle was too much for him. Old Peter Langley had gone on to say that he had received reports that Dick was using the field for smuggling purposes, and he did not care to be mixed up with business of that sort.

Dick knew, without being told, who had been the slanderer. His enemy, Joe Arnold was still trying to injure him.

Bennett Graham, his backer, came to the rescue once more and gave Dick the money, but the time limit was almost up. There were only about ten days left. And with Peter Langley believing him to be a crook, there was little hope of taking up the option without a personal interview.

Dick Mapes in his wheel chair, fretted and fumed at the problem facing him. Allan Graham, the son of his backer, and Syd Ames had been his first student-flyers and were now working at the field. They had been gone a week on a trip to Chicago. No one was left to take the long trip to Peru.

Of course he had Terry and Prim! Dick could trust Terry anywhere with a plane, but it was a long flight to Peru and there might be storms and dangers. Dick grew restless and impatient under the misfortune that kept him tied to his wheel chair.

"If I were only well enough to fly!" he fumed.

"But what's the idea, Dad! Don't you think I can _fly_ well enough?" Terry faced her father with flaming cheeks, her large brown eyes were flashing. "Why not send me?"

"Send you? To South America? Alone?"

"Not alone! Prim can go."

"But Terry, don't you realize that Peru is a long way off? You may have to face grave dangers, storms, fevers, savages! And while Peter Langley and his wife may be all right, you never can tell ahead of time what rough characters you may meet there!"

"What of it? I'm not afraid. You wouldn't think twice about sending Allan and Syd," said the girl with a frown.

Dick Mapes shook his head. "That's different," he said. "They are boys!"

"Which means that you don't trust me. You think I'm not a good flyer!"

Dick laughed. "Terry, don't be silly! I'd trust you to fly anything you could get off the ground. That isn't it. But I don't feel as if it would be right for me to let you risk your life."

Terry sat down beside her father's wheel chair and took his hand. "Listen Dad, while I talk. Haven't I proven over and over again that I'm a capable flyer. I'm pretty good at getting out of a jam in the air."

"I've said it often, Terry. I've never seen a better stunt flyer. You're clever and you _think_ when you're in the air! And that's what half the flyers don't do. That's why they crash."

"All right, so far, so good! We've been in lots of jams and got out of them by using our brains. Weren't Prim and I _The Gypsies Of The Air_, and didn't we go after the boys in Newfoundland and get them away from the kidnappers? Nothing terrible happened to us. Of course old Jim Heron kept us locked up and we had to think hard to find a way out of that old fortress, but we escaped without any harm." Terry's eyes were snapping as she recalled their imprisonment in the old fort.

"Oh, I know, Terry. You and Prim can look out for yourselves. But I don't like to send you into a jam deliberately."

"But Dad, you don't know that there _will_ be a jam, this time, and if there is, we can get out of it."

Dick did not answer as Terry hesitated and gave him a chance. The girl went on:

"Now we're in one of the biggest jams we've ever had yet. We're almost sure to lose our flying field, though we have the money to take up the option, because our enemy Joe Arnold has written mean letters to old Peter Langley and set him against us. Now you can see for yourself, if I could get down there before the option expires he would think differently."

"I know he would, Terry. But it's too dangerous. No."

"But it's the only way out. Allan and Syd are not here and may not be for a week. And we are apt to lose our flying field because you still have this one old-fashioned idea. You're up to date in every other way, Dad. What makes you think that girls can't look out for themselves?"

"Terry, you should have been a lawyer. You're wasted in aviation," her father said with a laugh. "You can make a fellow believe that black is white.--All right, if your mother consents, I will."

"That's passing the buck! You've got to answer 'yes' or 'no.' You know it will be a deadlock for mother always says, 'If you can get your father's consent, I suppose I'll have to agree!' and if that argument keeps up, the day for taking up the option will be long past and we'll have to give up the field."

Terry loved a struggle, her eyes were shining as she noted that she had almost reached success.

Dick Mapes slapped her hand playfully. "All right. When do you start?"

"At daybreak tomorrow," answered Terry in a business-like manner. "The plane needs a few repairs, small ones, then we're all set to go!" The girl wasted no time. The next minute she was running to the hangar, and drawing on an overall suit was getting ready to look over her plane.

Her mother, Alice Mapes agreed without a struggle. "In fact I don't feel half as frightened as I did when you went north to find the boys. You'll have a wonderful trip to the south. Your father and I trust you perfectly, we know you'll look over your plane at every stop and never take a chance with it."

"There you see, Dad!" said Terry with a happy laugh. "When mother agrees, it's bound to be all right."

Prim was already busy at their flying togs. There were a few repairs to make and this was left to Prim, who liked to sew and cook and do other domestic jobs while Terry was a good mechanic and kept the plane running without a hitch.

"A born flyer!" said Dick Mapes and he followed his daughter's figure as she tested her plane, listening intently to the hum of the motor, going over every part, making adjustments here and there to bring her plane to the highest pitch of efficiency. And when Terry was satisfied that _Skybird_ was in perfect running order, Dick Mapes could never find a flaw. Terry knew her job.

Bennett Graham had all the necessary legal papers ready and a certified check to close the deal, so there would be no hitch at the last minute. These papers were carried in a small brown leather case and sewn into the lining of Terry's flying coat.

Prim loved stylish clothes and her white flying suit was smartly cut. Terry turned to admire her pretty blonde sister just before they were ready to hop off.

"What's the idea of that necklace?" said Terry with a laugh. "Girl flyers don't wear necklaces with bright red jewels."

"Don't they? Well, this one does! It just suits my fancy, Terry Mapes. I think it looks smart, it adds a bit of color to my white costume."

"All right, Prim, just as you say. Now, is everything set? How about your sweet tooth. Got plenty of cake chocolate?" teased Terry, for Prim was always nibbling at something sweet.

"Sure, my pockets are full. Here put this little package of crackers in your coat. We may get hungry as we fly along. And I've put up a big lunch in case we need it."

At the last minute Prim adjusted the harness of the parachutes about Terry and herself not minding her sister's impatient shrugs of disdain.

For some reason Terry was always impatient of parachutes. She felt like an amateur even though she knew that many of the big flyers never went up without putting one on, as a safeguard in case of accident.

Terry looked with satisfaction at Sally Wyn, the little waif they had brought with them from the far north. The girl was fluttering about the field like a butterfly. She seemed to be in half a dozen different places at the same time, running errands and making herself useful. With Sally there, her father and mother would not be so lonely. The little orphan had found a place in the hearts of Dick and Alice, and they would not hear of her leaving them to go to work. With her happy disposition she kept the household filled with laughter. Alice often wondered how she had ever been happy without this fun-loving girl. And she had a way of making Dick forget that he was a cripple. She amused him.

As the girls said goodbye to her, Sally called out: "Next year Terry Mapes, I'll race you to Peru!"

It was a glorious morning, the sun was just rising as Terry sent her plane into the air and headed south. There were no last minute delays.

Now it remained for Terry and Prim to reach Peru, find old Peter Langley and convince him that he was mistaken and make him want to sell Dick the property. And in Terry's mind there was no doubt that she could accomplish it.

Below them was a vast stretch of fertile country with streams, lakes and broad green valleys. And high in the air, Terry's hand at the controls felt the spring of her little plane and was certain that _Skybird_ was thrilling at the adventure.

Terry held the plane down to a steady speed, hour after hour, only changing the monotony by diving to a lower level or rising to greater heights. They were following along the general line of the airway. They could pick out the landing fields and see the position of the great beacons that would flash at night to guide the flyer to the hangars on the ground.

Terry and Prim had decided to stay all night at the Waverly Field, far to the south. That meant steady flying all day, only coming down to refuel at long jumps.

They saw the lights of the Waverly Field a full half hour before they expected to be there. "Shall we go on?" asked Terry through the earphones. "We can easily reach the next landing field before dark."

"No, let's stay here. You look tired and besides I like the looks of this pleasure beach," replied Prim.

Terry put _Skybird_ into a steep spiral, leveled and circled the field and then put the plane neatly down on the ground.

Little did the girls think as they were greeted by the manager of the flying field that this was where their troubles would begin. That before they reached Peter Langley's mine they were to face an enemy who was desperate with greed and hate. And that at times the girls would despair of escaping with their lives!