For one thing, the sides, instead of drawing inward in a series of steplike shelves, were smoothed as glass from top to bottom. Only in the front was there a flight of steps. Not more than twenty feet wide was this flight, and the steps were less high and deep than those in an American home. The stairway was like a ribbon up the glittering, sleek side of the pyramid.

The top of the structure was flat, and on this stood a sort of temple, a flat stone roof supported by square, wondrously carved pillars. Except for the pillars, this was open at the sides, permitting glimpses of fantastically wrought idols of stone.

Strangest of all, perhaps, was the color of the pyramid. Of a grayish-brownstone, yet it glowed all over with a strange yellow, metallic aurora of tiny lights caught and cast back.

"Priceless!" murmured Johnny, the archaeologist.

"You said it!" grunted Renny, the engineer.

"From a historical standpoint, I mean!" corrected Johnny.

"I meant from a pocketbook standpoint!" Renny snorted. "If I ever saw quartz absolutely full of wire gold, I see it now. I'll bet the stone that pyramid is made of would mill fifty thousand dollars to the ton in free gold!"

"Forget the gold!" snapped Johnny. "Don't you realize you're looking at a rare sample of ancient Mayan architecture? Something any archaeologist would give both hands and a leg to inspect!"

As the plane dived closer, another thing about the pyramid became noticeable. This was a sizable volume of water which poured steadily down the pyramid side, coursing in a deep trough inlaid near the steps.

This water came out of the pyramid top by some artesian effect. Continuing away from the structure, it fed a long, narrow lake. This body of water in turn emptied into the stream that ran down the chasm up which Doc and his friends had flown.

Upon the sides of the egg-shaped valley, not far from the pyramid, stood rows of impressive stone houses. These were lavishly carved, strange of architecture. It was as though the flyers had slipped back into an age before history.

There were people — many of them. They were garbed weirdly.

Doc dropped the plane pontoons on the narrow lake surface.

IT was an awed group of men who peered from the plane as it grounded floats on the clean white sand of the tiny beach.

The natives of this Valley of the Vanished were running down the steep sides to meet them. It was difficult to tell whether their reception was going to be warlike or not.

"Maybe we'd better unlimber a machine gun?" Renny suggested. "I don't like the looks of that gang getting together in front!"

"No!" Doc shook his head. "After all, we haven't any moral right here. And I'll get out rather than massacre some of them!"

"But this land is all yours."

"In the eyes of civilized law, probably so," Doc agreed. "But there's another way of looking at it. It's a lousy trick for a government to take some poor savage's land away from him and give it to a white man to exploit. Our own American Indians got that kind of a deal, you know. Not that these people look so savage, though."

"They've got a pretty high type of civilization, if you ask me!" Renny declared "That's the cleanest little city I ever saw!"

The men fell to watching the on-coming natives.

"They're every one a pure Mayan!" Johnny declared. "No outside races have intermarried with these people!"

The approaching Mayans were going through a strange maneuver. The bulk of the populace was holding back to let a group of men, all of whom were garbed alike, come ahead.

These men were slightly larger in stature, more brute-like, of a thickness of shoulder and chest advertising powerful muscles. They wore a short mantle over the shoulders, a network of leather which had projecting ends rather like modern epaulets. They wore broad girdles of a dark blue, the ends of these forming aprons to the front and rear. Each man wore leggings not unlike football shin guards, and sandals which had extremely high backs.

They carried spears and short clubs of wood into which vicious-looking, razor-edged flakes of stone were fitted in the manner of saw teeth. In addition, each had a knife with an obsidian blade, and a hilt of wound leather.

Every one of these men also had his linger tips dyed scarlet for an inch of their length! None of the other tribesmen seemed to have the red fingers.

Suddenly the man who led this group halted. Turning, he lifted his hands above his head and harangued his followers in a voice of vast emotion and volume. This man was more stocky than the others. Indeed, he had Monk's anthropoid build without Monk's gigantic size. His face was dark and evil.

Doc listened with interest to the Mayan dialect as shouted by the speaker.

"That fellow is Morning Breeze, and the gang he is talking to are the sect of warriors, his followers!" Doc translated for his men, giving his own accurate deductions rather than the gist of Morning Breeze's speech.

"He looks more like an alley wind at midnight to me!" Monk muttered. "What's he ribbin' 'em up to do, Doc?"

Angry little lights danced in Doc Savage's golden eyes. "He is telling them the blue plane is a holy bird."

"That's what we wanted them to think!" said Renny. "So it's all right if — "

"It's not as right as you think," Doc interposed. "Morning Breeze is telling his warriors we are a human offering the holy blue bird has brought to be sacrificed."

"You mean — "

"They're going to kill us — if Morning Breeze has his way!"

Monk instantly whirled for the plane, rumbling: "I'm gonna meet 'em with a machine gun in each hand!"

But Doc's low voice stopped him.

"Wait," Doc suggested. "Morning Breeze's warriors haven't worked up their nerve yet. I have a scheme to try."

Doc stepped forward, advancing alone to meet the belligerent fighting sect of this lost clan of the ancient Mayans. There were fully a hundred red-fingered men in the conclave, every one armed to the teeth.

Seized with the insane fervor which comes upon addicts of exotic religions, they would be vicious customers in a fight. But Doc stepped up to them as calmly as he would go before a chamber of commerce luncheon gathering.

Morning Breeze stopped shouting at his followers to watch Doc. The chief warrior's features were even less likeable at close range. They were tattooed in colored designs, making them quite repulsive. His little black eyes glittered like a pig's.

Doc dropped his right hand into his coat pocket. Here reposed the obsidian knife he had taken from the Mayan who had killed himself in New York. Doc knew, from what he had heard in the Blanco Grande hotel room, that great significance attached to these knives.

With dignity, Doc elevated both bronze hands high above his head. In doing so, he carefully kept the sacred obsidian knife hidden from the Mayans. He had palmed it like a magician.

"Greetings, my children!" he said in the best Mayan he could manage.

Then, with a quick flirt of his wrist, he brought the knife into view. With such expert sleight-of-hand did he accomplish this that it looked to the Mayans like the obsidian blade had materialized in thin air.

The effect was noticeable. Red-fingered hands moved uncertainly. Feet shod in high-backed sandals shifted about. A low murmur arose.

While the time was opportune, Doc's powerful voice vibrated over the group.

"Myself and my friends come to speak with King Chaac, your ruler!" he said.

Morning Breeze didn't like this at all. A variety of emotions played on his unlovely face.

Watching the warrior chief, Doc catalogued the man's character accurately. Morning Breeze was hungry for power and glory. He wanted to be supreme among his people. And for that reason, he was an enemy of King Chaac, the ruler. The darkening of Morning Breeze's countenance at mention of King Chaac apprised Doc of this last state of affairs.