When the Flying Road Racer took the air the weight that the craft carried was distributed as follows:

Aluminum body, wheels, motor, suspension wires, etc. 900 pounds.

Five passengers. (approx.) 800 pounds.

Provisions, water, etc. 250 pounds.

(The provisions included canned goods, preserved butter, tea and cocoa, flour, sugar, salt and a few delicacies.)

Radolite crystals, instruments, etc. 275 pounds.

Other articles,—including Ned’s last-minute contributions. 300 pounds.

Total 2,525 pounds.

This left lifting power to raise 2,475 lbs., which, however, could be increased to a considerable extent by utilizing the reserve sections of the gas bag.

Jack roughly estimated the combined weights of those they were to rescue,—his father, his uncle, Abner Jennings and the two sailors,—at a little over one thousand pounds. Thus, it will be seen, that there was no reason why the Flying Road Racer should not be able to perform all that was required of her, with some lifting power left over for emergencies.

The boy inventors’ craft had been in the air about an hour when Tom descried, far below them, the gleam of a light. In that wild country it was not likely to betoken anything else but the site of Herrera’s plantation houses.

They all agreed on this, and Jack, after a consultation with his comrades, decided that the time had come to descend. The plan they arrived at, after threshing the situation over in all its bearings, was to drop in the most suitable place they could find, adjacent to the plantation buildings.

Then the gas bag was to be reinflated, ready for emergencies, and two of the party were to reconnoiter the ground as carefully as possible. The remainder of the rescue was to be left to circumstances. At one hour and ten minutes after midnight. Jack started the exhaust engine up.

Instantly the Flying Road Racer began to drop downward through space with her planes set at a slight angle, as Jack did not want to coast to earth too rapidly. This course soon brought the craft above the summits of the forest trees, at a safe distance from the light they had perceived from aloft. To make assurance of being unnoticed doubly sure. Jack had shut off the motor. Silently as a night bird the great bulk of the flying auto settled earthward.

All this time their eyes had been strained to sight an open space in which they might land without risk of damaging the balloon bag. Tom was the first to see, through the night glasses, such an area of cleared land amid the forest.

It was a tract about ten acres in extent, and formed, as they surmised later, one of the outlying fields of Herrera’s plantation. It had not yet been put into cultivation, however, and afforded as fine a spot for an air craft to ground as could be imagined. Half an hour after the descent had begun the Flying Road Racer settled as lightly as a bit of breeze-blown down on earth once more.

Thanks to her shock absorbers, hardly a jar was felt by those on board as she landed with her bag half deflated and limp and wrinkled. No time was lost in alighting and throwing out the anchors, contrived by Jack, used for securing the craft to earth in case of a sudden wind springing up. These anchors differed considerably from the sea type of “mud hook.” They consisted, in fact, merely of discs of iron shaped like an inverted mushroom. One edge of the disc was driven into the ground, and the shape of the holding appliances was such that an upward tug merely served to force them more deeply into the earth.

The adventurers figured that they were about half a mile to the west of the spot where they had seen the light, which they believed marked the site of Herrera’s plantation houses. They also estimated that there were left to them about two hours and a half more of darkness. There was urgent necessity then for immediate action.

Much to the chagrin of Tom and Ned, but to the huge delight of Jupe, who had no great fancy for the work in hand. Jack and Captain Andrews were to be the ones to do the reconnoitering. Tom and Ned were ordered to stand by the Flying Road Racer and be ready for any sudden development that might occur.

While Captain Andrews and Jack were absent, it would be the others’ duty also to refill the gas bag, so that the aero-auto might be ready for an instant ascent in case of need.

These preparations completed, the two who were to assume the most risky part of the night’s work each selected a fully loaded gas-gun. In addition. Captain Andrews carried an automatic revolver; but it was on the former weapons that they would largely depend.

There remained nothing more but the leave-takings, and the fervent wishes for success in the daring enterprise, coming from the lads who were to be left behind. These final ceremonies being disposed of, the grizzled old sailor and his young companion set off. Tom and Ned watched them till the shadows of the forest swallowed them up.

By good fortune, the two, upon whom so much depended, struck a trail almost immediately after their first plunge into the blackness that prevailed under the tropical trees. The path had evidently been used by the laborers who had made the clearing beyond. It was a broad, well-defined track, and their progress was rapid and almost noiseless.

Neither of them spoke as they made their way along the path. The situation was too critical for words, and Jack crept along behind Captain Andrews, hardly daring to breathe.

He was on the tip-toe of excitement and anxiety, as was natural. At the end of the trail they were following’ lay either success or dire failure. There was no middle ground. In the event of their failing in their mission. Jack could not disguise from himself that the consequences would be awful indeed. He had come in contact with Herrera only once, but that single occasion had amply sufficed to show him the character of the man.

From time to time, as they advanced, they paused and listened intently. But, except for the drone of the night insects of the jungle, and the occasional scream of a nocturnal bird, there was no sound other than the sighing of the breeze in the tree tops far above.

There is no place more mysterious than the jungle at night. The dense thickets seem to the nervous traveler to hold all manner of hidden perils. Some of these are not altogether imaginary, either. The cunning, cruel jaguar, the huge serpents, and a score of other dangers lurk in the shadows.

Fortunately, neither of our friends was burdened with sensitive nerves, and it was well they were not, for their errand was not one for timid folk to embark upon.

They glided along after all these pauses, making as fast time as possible. All at once Captain Andrews, who was in the lead, as we know, stopped abruptly.

So abruptly, in fact, that Jack almost collided with him.

“What’s the——” began Jack.

But instantly the Captain clapped a hand over his mouth. He raised the other in a gesture that Jack read instantly: “Silence!”

Just ahead of them. Jack now perceived, the path broadened and emerged on a considerable clearing. The black outlines of several buildings, were scattered about this open space.

From one of them hung a lantern, shedding a yellow patch of light all about it. This, evidently, was the light they had seen from above.

As they stood, still as graven images in the protecting shadows of the forest, a stalwart figure, with a rifle over its shoulder, paced into the circle of light and then vanished again.

“A sentry!” huskily breathed Captain Andrews. “If we thought we’d catch them napping we’ve been badly mistaken.”