"Don't know how it would work," replied Frank, smiling a little, however, at the faith Andy seemed to have in a blazing brand, now that he could look back to his late experience with the jaguar. "Never heard that snakes were afraid of fire. And besides, there's no need. Now keep quiet, and watch. You'll see something worth while; but be ready to jump clear."

He had already dropped down on one knee. The Marlin stock rested against his cheek, and his eyes sighted along the barrel. Andy fairly held his breath, his startled eyes glued on that swaying head of the monster.

Then came the sharp report as Frank pulled the trigger. He instantly jumped back, and by a rapid motion of his hand sent another cartridge into the chamber, the clever mechanism of the gun proving that it was built so as never to fail in an emergency.

Andy had accompanied his chum in that backward movement; but never for an instant did he remove his eyes from the strange spectacle that was taking place there in front of them both.

Undoubtedly the well aimed bullet had crashed through the fearful head of the suspended anaconda. Instantly it released its many coils above, and a tremendous length of writhing snake could be seen whipping over the ground. Nothing in the way of small vegetation could stand in the path of those powerful springy coils, as they shot this way and that.

"Oh! my!" gasped the astounded Andy, as he moved farther back, so as to avoid any chance contact with the flying destructive force that was leveling everything in the glade for twenty feet around. "Did you ever see anything to equal that? Talk to me about your harvesting machines, here's one that's got 'em all beat to a frazzle. Ain't he ever going to give up the ghost, Frank? Guess these anacondas must have the nine lives of a cat!"

"Well," remarked Frank, "you must have forgotten that among boys it's said that a snake won't die till sundown. I've seen one's tail wiggle hours after we thought the thing was stone dead. There, he's moving off into the forest, and a good riddance. While I'd like to measure the serpent just from curiosity, we've got no time to waste waiting for him to kick the bucket."

"That's right," a.s.sented Andy. "And as for going anywhere near such a whirlwind, you'd have to excuse me."

They watched the dying anaconda gradually vanish in the depth of the forest; and both boys were glad that it had turned out that way, since they were anxious to depart from the place.

"Don't I wish I'd had my little camera along, so I could have snapped a shot at that dandy chap! The fellows would believe me then, when I told about what happened to us here. And anyway, Frank, I don't think we'll forget this camp, do you?"

"Well, hardly," replied his chum, smiling broadly. "Because we've sure had enough happen to us here to make us remember. But I'm glad to find there's going to be more s.p.a.ce for the run than I thought at first."

"We'll need every inch of it," declared Andy, as he looked dubiously at the tops of the lower trees about the place where the snake had held forth. "Don't I wish we'd brought a few sticks of dynamite along, though."

"For goodness' sake, what would we want with dynamite? Think you could have blown up that snake, do you?" asked Frank, as they started to cross the glade toward the waiting monoplane.

"Oh! shucks, no. I was thinking how we could plant 'em under a bunch of those trees and enlarge the gap!" declared Andy.

At that Frank burst out into a hearty laugh.

"What a fellow you are for wild notions. Think of us blowing up the forest to make an aviation field! I reckon, however, seeing that you haven't got the dynamite, Andy, we'll have to do the best we can. Take hold here and we'll push the machine just as far back as it will go. Perhaps we can gain a few yards at this end that will count in the long run."

Frank was particularly careful about every little detail. He knew just what he had to depend on. In the past he had made it a pet hobby to rise in as short a s.p.a.ce as possible; and now this faculty seemed destined to prove a valuable a.s.set in their speedy climbing up.

"All ready?" he asked, grimly.

Andy took one last look at the face of his chum. He saw that Frank's mouth was compressed in that firm way that stood for so much; and somehow Andy's wavering confidence returned in full measure. When Frank Bird looked like that, things always had gone according to his will; and they must now!

"Yes, I'm fit, Frank," he said, quietly. "Let her go when you're ready!"

In the many times that the two boys had made ascents, Andy could never remember that his pulses throbbed with one-half the suspense they did now. Not even on that never to be forgotten initial performance, when for the first time they felt the strange sensation of leaving the solid ground in a flying machine, had he been so excited, so nervous, so filled with alternate hope and fear.

Frank had taken every possible precaution. He had thoroughly studied the ground, and made sure that no obstacle would be apt to cause the running gear of the aeroplane to swerve, and thus throw them off their course.

All he could do was to start the machinery, get a rise at the quickest possible second, and be ready to shut off power if he realized that the feat they were about to attempt were impossible, so as to avoid smashing the planes against a tree.

"Then here goes!" he said, calmly.

Andy held his breath as he heard the engine start off at a tremendous speed. He felt as though a giant hand had plucked them from the spot where the aeroplane had been planted for the start. Across the glade they went speeding. His heart almost jumped into his mouth he believed, as he felt the little craft start to leave the ground, as Frank manipulated the planes, and elevated them so as to catch the air under the broad blades.

They were rising rapidly now! Would they manage to clear those terrible treetops that stood like a grim barrier in their path?

Higher yet did Frank throw the planes, so that they actually seemed to be climbing straight upward, according to the vivid imagination of Andy; who, clutching the upright at his side, waited for what was going to happen.

It was too late now to retreat! They had gone too far to stop, and try again! No matter whether for good or ill, their kite had been tossed to the winds of heaven, and they must abide by the consequences.

Andy gave one little squeal, for it could not be termed anything else under the sun. This was when they shot past the most prominent branch of the tree that happened to stand directly in the way of the rising aeroplane. Andy believed that the wheels below must have actually brushed through the foliage, for he always declared that he heard a fierce "swish" as they pa.s.sed.

Had they caught even one little bit, something dreadful might have happened, and the precious aeroplane, on which everything depended, meet its sad fate; not to speak of the nasty fall the Bird boys would have suffered.

But Fortune was once more kind to the young adventurers. They pa.s.sed safely through the peril, and were speedily fully launched upon the wide open expanse of s.p.a.ce!

"Hurrah!" shouted the exultant Andy; but it might be noticed that his voice was a bit husky, even as his face seemed chalky white.

"A close shave," remarked Frank; who himself had been rigid while they were thus taking such desperate chances; "but we made it, thank goodness! I hope that will be a lucky token of what the day has in store for us."

"Amen!" echoed his chum; and there was no levity in his tones, either.

The sun was just rising. Below them lay the dense foliage of the almost impenetrable forests, from which they had just made this almost miraculous escape. And both young aviators, as if by common consent, started to sweep the horizon around with their eyes.

"See anything of it?" asked Andy, eagerly.

"I thought I did away over yonder toward the mountains; but I guess it must be a big bird hovering high up, a condor perhaps," Frank replied.

"Well, there isn't any sign of the biplane, that's sure," Andy went on in a relieved voice. "Perhaps they didn't have as good luck in landing as we did, and had a nasty spill. Don't I hope they busted some of the planes, or part of the little old Gnome engine, so we won't have to be bothered with 'em again?"

Frank made no remark. While as a rule he refused to let anything like bitterness dwell in his heart, still, this was a case where everything was at stake; and if the bothersome revolutionists kept chasing them in the biplane they were apt to give a great deal of trouble. And secretly he could echo Andy's wish that the biplane might be temporarily crippled, so as to be unfit for flying.

"Now, what's the programme?" asked Andy, when they had covered several miles.

"We've just got to head for the mountains yonder," replied his chum. "You know, he declared it was a valley that lay among the mountains; and it must be, to be surrounded by high cliffs. Once we get among the hills, we'll sail back and forth, combing the whole region, and hoping sooner or later to discover his queer prison."

Andy lapsed into a state of silence; but he kept watching ahead as they drew gradually nearer the uplifts. Doubtless but one thought held dominion in his mind, and this was that somewhere amidst those same mountains the father whom he loved so dearly was waiting, and hoping for an answer to his appeals for aid.

CHAPTER XXI.

THE LAST LITTLE HOT AIR BALLOON.

"Did you ever see a wilder region?" asked Frank, about the middle of the morning, when they had alighted on a broad, level plateau, so as to allow him to look over some little matters connected with the engine, that he believed needed attention.

Andy had been using the binoculars pretty much all the time they were aloft, but without any success. Many times be began to think he had sighted something that looked like cliffs rising up, and a wild hope had seized upon his devoted heart; but upon Frank bringing the airship in that quarter, in answer to his frantic appeals, it had proven to be a false clue.

Cliffs they saw in plenty, but as yet none enclosing a valley so as to imprison an unfortunate aeronaut, whose runaway balloon had dropped with him into its depths.

Still, the day was not nearly half over. And the monoplane behaved splendidly; so that they could hope to continue the search as long as their supply of gasolene held out.