"What do you mean, boy?"

"That we can a.s.semble the Golden Eagle in a couple of hours if you will give us the men to help."

Captain Hazzard thought a minute.

"It seems to be the only chance," he said at last, "but I don't know that I ought to let you a.s.sume such responsibility."

"We will be in no greater danger than the professor is; much less, in fact," urged Frank. "Please let us go. If we can save his life it is worth running the risk."

"Perhaps you are right, my boy," said Captain Hazzard at length, "at any rate, promise me to run no unnecessary danger."

The promise was readily given and with a cheer the men set to work to hoist the cases containing the sections of the aeroplane over the side and row them ash.o.r.e. The work was carried on under the glare of the searchlights of the two ships. In two hours' time the Golden Eagle was ready for an engine test which showed her machinery to be in perfectly good trim.

"She is fit for the flight of her life," declared Frank, as he stopped the engine.

"Is everything ready?" asked Captain Hazzard.

"Yes," was the reply, "except for two canteens of water, some condensed soup tablets and two tins of biscuit."

"You have your weapons?"

"I have sent to the ship for two 'Express' rifles, each carrying a heavy charge and explosive bullets. In addition we have our revolvers and some dynamite bombs--the ones that were designed to be used in blasting polar ice," said Frank.

"One moment," said Captain Hazzard. He turned and hailed the ship: "Bring over six of the naval rockets from the armory!" he ordered.

"If you should need help," he said, in explanation of his order, "send up a rocket. They are made so that they are visible by day as well as night. In the daylight their explosion produces a dense cloud of black smoke visible at several miles. They also make a terrific report that is audible for a long distance."

The same boat that brought the boys' weapons carried the rockets and their provisions and at about four a. m. they were ready for their dash through the air. At the last minute it was decided to take Billy Barnes along as he knew something about handling an aeroplane and in a pinch could make himself useful.

"Good-bye and good luck," said Captain Hazzard fervently as the engine was once more started, with a roar like the discharge of a battery of gatling guns. From the exhausts blue flames shot out and the air was filled with the pungent odor of exploding gasolene.

With a wave of the hand and amid a cheer that seemed to rend the sky the Golden Eagle shot forward as Frank set the starting lever and rushed along over the level plane like a thing of life. After a short run she rose skyward in a long level sweep, just as the daylight began to show in a faint glow in the east.

It rapidly grew lighter as the boys rose and as they attained a height of 1,500 feet and flew forward at sixty miles an hour above the vast level tract of gravelly desert, by looking backward they could see the forms of the two ships, like tiny toys, far behind and below them. On and on they flew, without seeing a trace of the professor or the band that had undoubtedly made him prisoner.

"We must have overshot the mark," said Frank, as he set a lever so as to swing the aeroplane round. "We shall have to fly in circles till we can locate the spot where the Patagonians have taken him."

They flew in this manner for some time, sometimes above rugged broken land with great sun-baked clefts in it, and sometimes above level plains overgrown with the same dull colored brush they had noticed fringing the coast.

Suddenly Billy called attention to a strange thing. All about them were circling the forms of huge birds. Some of them measured fully ten feet from wing tip to wing tip. They had bald, evil-looking heads and huge, hooked beaks.

"They are South American condors, the largest birds in existence,"

cried Harry, as the monstrous fowls, of which fully a hundred were now circling about the invaders of their realm, seemed to grow bolder and closed in about the aeroplane.

"They mean to attack us," cried Frank, suddenly.

[Ill.u.s.tration: "They Mean to Attack Us."]

As he spoke one immense condor drove full at him, its evil head outstretched as if it meant to tear him with its hooked beak. The boy struck at it with one arm while he controlled the aeroplane with the other and the monstrous bird seemed nonplussed for a moment. With a scream of rage it rejoined its mates and they continued to circle about the aeroplane, every minute growing, it seemed, more numerous and bold.

"We shall have to fire at them," cried Frank at last. "If they keep on increasing in numbers they may attack us all at once and wreck our airship."

Hastily Harry and Billy unslung their heavy "Express" rifles and began firing. Ordinarily it is no easy task to hit a bird on the wing with a rifle, but so large a target did the huge bodies present that four fell at the first volley. As they dropped some of their cannibal companions fell on them and tore them to ribbons in midair. It was a horrible sight, but the boys had little time to observe it. Their attention was now fully occupied with beating off the infuriated mates of the dead birds, who beat the air about the aeroplane with their huge wings until the air-storm created threatened to overbalance it.

Again and again the boys fired, but failed to hit any more of the birds, although feathers flew from some of the great bodies as the bullets whizzed past them.

All at once the condors seemed to come to a decision unanimously.

Uttering their harsh, screaming cries they rushed at the aeroplane, tearing and snapping with beak and claws. The machine yawed under their attack till it seemed it must turn over. Still, so far, Frank managed to keep it on an even keel.

"Bang! bang!" cracked the rifles again and again, but the loud angry cries of the birds almost drowned the sharp sound of the artillery.

It was a battle in the clouds between a man-made bird and nature's fliers.

Suddenly Frank gave a shout.

"The dynamite bombs!"

Swiftly and cautiously Harry got one of the deadly explosives ready.

They were provided with a cap that set them off when they encountered any solid substance, as, for instance, when they struck the earth, but a small, mechanical contrivance enabled them to be adjusted also so that they could be exploded in midair.

"Isn't there danger of upsetting the aeroplane?" gasped Billy, as he saw the preparations.

"We'll have to chance that," was Harry's brisk response, "the birds are too much for us."

As he spoke he leaned out from the cha.s.sis and hurled the bomb high in the air. As he cast it out there was a slight click as the automatic exploder set itself.

"Hold tight," shouted Frank, setting the sinking planes.

The aeroplane rushed downward like a stone. Suddenly a terrific roar filled the air and the boys felt as if their ear drums would be fractured. The aeroplane swayed dizzily and Frank worked desperately at his levers and adjusters.

For one terrible moment it seemed that the Golden Eagle was doomed to destruction, but the brave craft righted herself and soared on.

The bomb had done its work.

Of the huge flock of condors that had attacked the Golden Eagle only a bare dozen or so remained. The rest had been killed or wounded by the bomb. The survivors were far too terrified to think of pursuing the boys and their craft further.

"Thank goodness we have escaped that peril," exclaimed Harry, as they sailed onward through the air; "who would ever have thought that such birds would have attacked an aeroplane."

"They frequently, so naturalists say, carry off babies and small animals to their rocky nests," was Frank's response, "and birds as bold as that I suppose resented the appearance of what seemed another and larger bird in their realm."

For an hour more the aeroplane soared and wheeled above the baking hot plains intersected by their deep gullies, but without result. The boys with sinking hearts were beginning to conclude that the professor had been carried off and hidden beyond hope of recovery, when Harry, who had been peering ahead through the gla.s.ses, indicated a distant spot behind a ridge with much excitement.

"I can see a horse tethered there," he cried.

The aeroplane was at once shot off in that direction and soon all doubt that they were in the vicinity of a band of Patagonians vanished. As the air craft rushed forward several tethered horses became visible and a column of smoke was seen rising from a deep gully behind the ridge. No doubt the Patagonians thought themselves well hid.

So secure did they feel, seemingly, that not even a sentry was visible.

"Do you think they are the same band that kidnapped the professor?"