AS the ship moved slowly into port, Mr. Lewis, standing anxiously on the deck, caught sight of his friends and waved wildly. Obviously he was exceedingly glad to see them again.

Others of the expedition who recognized Mr. Holton or the boys also waved a friendly greeting, which was returned by those on shore.

When the boat had come to a standstill, a huge crane swung out and up to the deck. At the end, attached by a massive hook, was a chair. Into this the boat’s passengers were to sit and be hoisted down to the dock.

“Funny way of unloading passengers,” laughed Bob, as he watched a woman rather nervously sit down in the chair.

“No other way, I guess,” came from Mr. Wallace. “The surf billows roll too high for the conventional method.”

The onlookers watched closely as the chair was raised off the deck and suspended over to the shore.

The woman who was carried in this manner laughed as she left the chair and turned to see the motion repeated. From the look on her face, it had been an exciting experience.

“Here comes Dad!” observed Joe happily. “Wonder how he’ll like it?”

Mr. Lewis had seated himself in the chair and was being carried high in the air to the dock.

When he set foot on the ground, he rushed toward the others, on his face a look of intense joy.

Words fail to describe the meeting that followed. Mr. Lewis was literally mauled by his son and friends, who were overjoyed to have him again with them. Especially was Joe happy.

“I worried from the time you left Washington,” the naturalist told them, throwing an arm over Joe’s shoulder. “The more I thought about that airplane trip the more anxious I became. You didn’t have any trouble, did you?”

“It’s according to what you call trouble,” laughed Bob. “If you mean accidents, we didn’t have any. But if you mean just common bad luck, we had plenty.”

“Could have been worse, though,” his father reminded him. “And let me tell you that Karl is an excellent pilot. If he weren’t, we probably wouldn’t be here now.”

“As if I didn’t know it,” smiled Mr. Lewis, glancing at the blushing aviator. “If anyone else had offered to take you to Peru, I wouldn’t have thought much of the idea. Karl Sutman, though——”

At this moment a group of men came up, to be recognized by Mr. Lewis and Mr. Holton.

The youths, Mr. Wallace, and Karl were introduced to them as members of the archÆological and geological divisions of the expedition. Dr. Rust, Professors Allan and Kelley, and Mr. Dunn, as their names were, had come to this region to search for additional Inca ruins and to study the land in the mountain section.

Two other men completed the personnel of the expedition. They were Mr. Buenagel, assistant, and Dr. Brown, physician, both of whom had been on numerous expeditions with the others. They now came up and received the same hearty welcome.

“Now that we’re all together,” began Dr. Rust, “we want to decide where we’ll make our headquarters. Is everyone in favor of having our base in or near Cuzco?”

“I should say yes,” came from Professor Kelley. “Cuzco, after all, is a very strategic point, and is quite easily accessible from all parts of this section. So why not locate there?”

As everyone agreed, the question was settled. Now came the problem of transporting the expedition’s supplies, of which there were many.

Karl generously offered the services of the monoplane in getting the trunks and bags over to Cuzco. He explained that he would be glad to do this for them, even though it might be necessary to make two or three trips.

But Dr. Rust, leader of the expedition, stoutly refused.

“We don’t wish to put you to that trouble,” he said. “As long as there is a railroad running up to Cuzco, we’ll make use of it and have our stuff shipped, even though it may take a few days longer.”

Karl wondered afterwards if the scientist secretly feared an accident. The tall young man remarked to Bob and Joe several days later that perhaps Dr. Rust did not wish to take a chance on the monoplane crashing with the expedition’s supplies on board.

As had been suggested, the supplies, including those of Mr. Holton and Mr. Lewis, were placed on board the first train that left for Cuzco. The boxes and trunks would not reach their destination until several days later, however, since it was necessary for them to be changed around several times.

Except for the three naturalists, the scientists boarded the same train for Cuzco. Mr. Wallace and the youths’ fathers were to accompany Karl and Bob and Joe in the monoplane. With Mr. Lewis in the cabin, there would be an added load, but Karl told them it would not be dangerous.

“Just have to watch the take-offs and the landings more closely,” the aviator explained. “Outside of that, we’ll never know that another person is inside, as far as the ride goes.”

“Won’t ride any easier?” queried Joe, trying to appear innocent.

“Quit your kidding!” snapped Karl with a laugh. “This bus isn’t an automobile.”

“But a bus is an automobile,” said Joe persistently.

He dodged a pass that Karl swung at him. Then, seriously, he turned to the others, who were busy attending to minor tasks about the airplane.

“Everything’s ready,” announced Mr. Wallace, stepping inside the cabin. “Suppose we get started at once, so as to get there and look around some before the others arrive by train.”

Karl was willing. He climbed into the cockpit and started the engine. Mr. Holton, the last to enter the cabin, closed the door tightly just as the monoplane began rolling over the field.

“We’re off for Inca land!” shouted Bob excitedly, raising a motion-picture camera to his shoulder. “And won’t we have fun!”

“We’ll also have a little work,” said his father quietly. “If we get enough specimens from this region to satisfy the museum heads we’ll have to go some.”

Flying over this interesting land was exciting to the youths, who viewed the sights curiously. Before long they could make out the town of Arequipa away over to their right, and just behind it, El Misti volcano, whose sides sloped up to a point.

Karl guided the ’plane as near the ground as possible, knowing that he and his friends could not stand the rare air of several thousand feet higher without the use of oxygen. A few tanks of this valuable gas were now on the train en route to Cuzco. Karl had not thought it necessary to use them in the ’plane so soon.

At the speed they traveled, it did not take them long to sight Cuzco in the distance. Several miles away they could also see the town of Anta, which was a mere village compared to its neighbor city.

When they came nearer, Karl flew straight for the central plaza, so as to get a fine view of all the buildings and places of importance.

“Look at the people swarming to see us,” said Joe. “I guess it isn’t often that an airplane comes here.”

At about three hundred feet they soared leisurely over the central plaza, where natives were gathering rapidly. Directly below them was the huge cathedral, which, as far as they could see, was the most imposing building in the city. All about were low structures, with an occasional higher building dotting the landscape.

It was a wonderful view. Even from that low altitude, the explorers could easily make out the surrounding mountains, on many of which were Inca ruins, including the “staircase farms.”

Joe considered it a wonderful opportunity to take several hundred feet of motion pictures. He pointed the camera first at the city below them, then at the near-by mountains, turning the crank continuously.

When he had flown a few times around the town, Karl picked out a level stretch to the east and began the dangerous task of landing. Well he knew at that altitude it would be easy to crash.

The monoplane headed downward at high speed, the wheels touched the ground, bumped back into the air, touched the ground again. The machine rolled ahead at fifty miles an hour, forty, thirty, and finally came to a stop dangerously near a large pile of stones.

“All out,” called Karl, when he had switched off the motor. “We’re here. And we came down without a smash-up.”

Directly across the river Almodena the adventurers could see Cuzco, looking strangely quaint in its pocket in the mountains.

“Here come more natives,” observed Mr. Holton, as a horde of twenty or thirty men, women, and children rushed toward the Americans.

As they came nearer, they uttered something that none of the newcomers understood.

“They’re speaking in Quichua—that’s the native tongue in this part of Peru,” explained Mr. Lewis. “It’s the same language that was used by the ancient Incas.”

Although the natives scrutinized the airplane carefully, they were not bothersome, staring rather in awe at the great “bird” that had come mysteriously to their city.

Karl thought it best to have the craft guarded against possible marauders. But how he could secure a guard was a problem, since none of the Indians could understand English or Spanish. And the aviator knew not one word of Quichua.

“Suppose we take turns watching it,” suggested Mr. Holton. “I’ll take the first watch of, say, two hours. Bob, you can take the second, and so on until we can make some other arrangements.”

“And while Dad’s staying here with the ’plane,” began Bob, “I’d like to look around a bit. Anybody want to go with me?”

“Sure.” Joe was anxious to see the sights in this strange land.

“Don’t be gone long, boys,” cautioned Mr. Lewis. “We all want to be on hand when the train arrives from Mollendo.”

The chums walked south over a level plain, hoping to see something of interest before long.

They had not long to wait. In a little open grassy stretch beside a wall of rock was a herd of ten or twelve llamas, grazing peacefully. These animals were about 4 feet high, with long necks and a head like that of the camel.

“Let’s go up and see them,” said Bob, moving over to the herd.

“Better not,” warned Joe. “They might be dangerous.”

“Dangerous? Those things dangerous? Wait a minute and I’ll show you how peaceful they are.”

Bob had walked up to the foremost black animal and now began to stroke its woolly back.

Then an unexpected and unpleasant thing happened. The llama turned suddenly on Bob and spat violently in the youth’s face.