CHAPTER XI--SPYING ON THE ENEMY

"There is that man again, Mr. Parks."

"Duske? Yes."

"Shall I follow him?"

"I'd like to know just what he is about."

"I would like to try and find out," declared Andy, with more eagerness than his employer suspected.

"All right, Andy; look him up a bit. Watch out for trouble, though, for he is a dangerous man."

It was late in the afternoon of the day succeeding Andy's sensational performance, and Parks and his young assistant were again on the aviation field.

Andy had made out the man whom Parks had called Duske carrying two cans of gasoline past a tent. He did not seem to have observed Parks, and Andy did not believe that he knew him. Andy left the side of his employer, and, circulating around kept Duske in sight from a distance.

The boy had not said anything to Mr. Morse about Duske. He felt certain that Duske was one of the enemies the inventor had described. Just at present, however, Andy considered it would be unwise to disturb Morse. The latter had almost completed the new airship. His mind was absorbed in his task, and he was working day and night.

Duske passed the last tent on the field, and then struck off beyond some old railroad sheds to the side of an abandoned switchyard. Scattered here and there over this space were several tents. They were occupied by aero contestants who had not been able to get a favorable location on the big field, or by those who had sought this seclusion because they wished to be isolated with some fancied new invention, the details of which they did not wish their contestants to learn.

Finally Duske seemed to arrive at his destination. It was where stout canvas had been stretched about fifty feet out from the blank side of an old frame shed. These strips of canvas and the shed cut out completely a view of what was beyond. The front of this enclosure was guarded by a roof set up on posts, this leading into the entrance tent of the main enclosure.

A man about as sinister looking as Duske himself was cooking something on a stove, and two others were lounging on a bench near by. Duske carried the gasoline cans out of sight. Andy got around to the side of the enclosure, way back near its shed end.

It was getting well on toward nightfall, and he felt that he was secure in making some bold, prompt investigations. There was no doubt that the large tent enclosed the airship which Duske and his crowd intended to enter for the race. Andy attempted to lift the canvas at one or two points, but found it securely pegged to the ground.

"Humph!" he soliloquized, "everything nailed down tight. Must make their trial flights at midnight. They must think they have got a treasure in there. I've got to see it."

Finally Andy came to a laced section of the canvas, which he was able to press apart a foot or more by tight tugging. He squeezed through, and stood inside the enclosure.

There was light enough to show outlines, and with a good deal of curiosity Andy walked around and inspected an aeroplane propped up on a platform in the center of the enclosure. He came to a halt at one end of the machine. Two long hollow tubes extended beyond the folding planes.

"Why," breathed Andy, "it's the idea they stole from Mr. Morse. Here's the suction apparatus, and all!"

"Hi, there! who are you?"

The challenge came so sharp and sudden that Andy was taken completely off his guard. Two men had come from the front tent, their footsteps being noiseless on the soft earth floor. One of them was the man Duske.

"Just looking around," replied Andy, edging away and pulling his cap down over his eyes.

"How did you get in here?"

"Slit in the canvas."

"Don't let him go--grab him," ordered Duske's companion quickly, and Andy began to back towards the canvas.

Duske reached out and made a grab at Andy. The latter dodged, but Duske's hand landed on his cap. His glance falling to the inside peak, he could not help reading there the words: "_Eagle_--Andy Nelson."

Nearly everything worn by Parks and Andy, as all the parts of the _Eagle_, were marked, so that in case of an accident identification would be easy.

"_'Eagle'!_" cried Duske, bristling up. "Do you belong to the _Eagle_ crowd?"

"He's a spy--head him off!" shouted the other man.

"_'Eagle'_--'Andy Nelson'," continued Duske. "That's your name, is it? Now then, what are you snooping around here for?"

"What's that, what's that?" challenged the other man quickly. "'Andy Nelson?' Say, Duske, that sounds familiar. I just read that name somewhere--I have it--in a newspaper----"

"Thunder! he's slipped us," exclaimed Duske.

Both men had started for Andy. The latter let them come on, ducked down, dove straight between them, ran to the slitted canvas, squeezed through, and sprinted away from the spot on feet of fleetness.

"I don't know how much I have mixed up affairs," he reflected, as he made for the home camp. "Those fellows know my name and that I am with Mr. Parks. What bothers me most, is what the man said about seeing my name in a newspaper. Some one here--in an automobile."

As Andy reached home he observed an automobile in front of the living quarters. A man came out as Andy stood wondering who the visitor could be. Andy noticed that he carried a small black case.

"A doctor," he decided hastily. "Can any one be sick? What has happened?" he asked, as Scipio came out.

"Hahd luck, chile, hahd luck!" replied the cook very seriously. "Yo bettah see Mistah Parks right away."

Andy hurried to the sitting room. Lying covered up on a couch, his right arm in splints, and looking pale and distressed, was the aeronaut.

"Oh, Mr. Parks! what is the matter?" asked Andy in alarm.

"Everything off, lad," replied his employer, with a wince and a groan. "I've had a bad fall, arm broken in two places, and we can't make the airship race."