motor reached their ears. Doc, with all his keenness of hearing, could detect but the faintest drone of the motor. But he knew the explanation. The terrific winds that comprised the air currents over the chasm were sweeping the sound waves aside.
'I am worried!' benign King Chaac confided in shaky tones. 'My people and the warriors are being whipped into a religious frenzy by Morning Breeze. I fear they will attack you.'
Doc nodded. He could see that very thing impending. There was certain to be violence unless he did something to prevent
'The blue bird you see above is supreme!' Morning Breeze was shrieking. 'It is all-powerful. It is the chosen of your gods! It has no white-skinned worms inside it! Therefore, destroy these white worms in your midst!'
Doc reached a decision.
'Stand by your guns!' he directed his men. 'If you have to, shoot a few red-fingered men. But try holding them off a while. Renny, you come with me!'
Doc's friends' whipped out automatic pistols, which they had kept under their clothing. These automatics were fed by sixty-cartridge magazines, curled in the shape of compact rams' horns below the grips. The guns were what is known as continuously automatic in operation — they fired steadily as long as the trigger was held back. Both guns and magazines were of Doc's invention, infinitely more compact than ordinary submachine guns.
At the display of firearms, excited cries arose from the populace. Ample proof this, that they understood what guns were.
Doc and Renny sprinted for their plane.
Amid a great splashing, Doc and Renny waded out to the low-wing craft and hoisted themselves into the cabin. Doc planted his powerful frame in the pilot's bucket.
'Now if the engines haven't been tampered with!' Renny grated, anxiety on his long, puritanical face.
Doc stepped on the electro-inertia starter buttons. The port motor popped black smoke out of the stacks, then started turning over. Nose engine, starboard — both functioned.
Vastly relieved, Renny lunged back in the cabin. His monster, flinty hands tore the top from a metal case as another man would open a cigarette pack. Out of the case came the latest model of Browning machine gun, airplane type. An ammo box gave way to his iron fingers. The cartridges were already in long snakes of metal link belt.
The low-wing speed plane was going down the narrow lake now. Renny threaded a belt into the Browning. The gun was fitted with a rifle-like stock.
At the lake end, Doc jacked the ship about with sharp bloops of the engines. The craft gathered speed, a run of the whole lake length ahead of it. On step, it went. Then into the air.
With a touch little short of wizardry, Doc banked the speedy plane before it shattered itself against the sheer stone sides of the chasm. In tight, corkscrew turns, climbing, using all the power of the motors, Doc mounted out of the great cut.
Overhead the blue monoplane still lurked.
The treacherous air currents seized Doc's plane, worried it like a Kansas whirlwind would a piece of paper. Once, despite his expertness, Doc found himself doing a complete wingover. He recovered, continued to climb out of the Valley of the Vanished.
The air currents, after an interminable battle, became less violent. Doc pointed the great ship's nose up more steeply.
Suddenly the blue monoplane came hoicking down the sky lanes to the attack. Grayish wisps like spectral ropes suddenly streaked past Doc's ship. Tracer bullets! The monoplane was evidently fitted with a machine gun synchronized to shoot through the propeller blades!
Doc had not expected that — the blue plane had not possessed such armament when it attacked him in Belize. But he was not greatly perturbed. At his back was Renny, whose equal with a machine gun would be hard to find. Renny knew just how to lean into the firing weapon so as to withstand the recoil and still maintain an accurate aim.
Renny's Browning abruptly released a long, ripping burst. The blue monoplane rolled wildly to get clear of the slugs that searched horribly for its vitals.
'Good work!' Doc complimented Renny.
Then it was Doc's turn to sideslip-skid his ship out of the procession of slugs that were eating vicious holes in the left wing end. The pilot of the blue plane was no tyro.
Warily the ships jockeyed. Doc's plane was infinitely the larger, but that was certainly no advantage. And its control surfaces were not designed for combat flying. The two crafts were nearly evenly matched, with Doc having the great edge in speed on a straightaway. But this was no straightaway.
Lead from the other ship chewed at the fuselage, well to the rear.
'Now, Renny!' Doc breathed — and stood his ship on one wing tip.
Renny's Browning hammered and forked one long tongue of red from the barrel.
The burst punctured the pilot of the blue plane! The ship careened over, motor full on. It bored in a howling, unguided dive for the craggy mountaintop.
Its antics were even wilder as the air currents gripped it. Far to one side it skittered, then back. A gigantic suction drew it down into the Valley of the Vanished.
Striking in the deeper part of the lake, it raised a great geyser of foam.
By the time Doc had battled the rigorous air down to the lake surface, not a trace of the blue monoplane was to be seen.
Doc taxied over to the beach below the pyramid. He sprang ashore and ran up the sloping floor of the valley. Directly for Morning Breeze Doc raced. Now was the time for slam-bang stuff!
Long Tom, Johnny, Ham, and Monk had not been harmed as yet. But they were ringed around with agitated Mayans. The Mayans seemed to want to attack the white men as Morning Breeze advised, but at the same time were afraid of Doc's wrath. For the resurrection had given them the idea Doc was a superior being. He had killed the blue bird, too.
Morning Breeze saw Doc bearing down on him. Terror seized the squat, ugly-faced culprit. He shouted for his fellow warriors to protect him. Four of these advanced. Two had short spears. Two had the terrible clubs with razor-sharp flakes of obsidian embedded in the heads. Emboldened by Morning Breeze's shrieked orders, they rushed Doc. And fully fifteen more warriors, all armed, joined the attack.
What followed went into Mayan history.
Doc's bronzed body seemed to make a single move — forward. His great, powerful arms did things with a blurred, unbelievable speed.
The two spearsmen reeled away without making a thrust. One had a face knocked almost flat by Doc's fist; the other's right arm was broken and nearly jerked from his body.
The two club wielders found themselves suddenly pushed forcibly together by two hands which apparently possessed the power of a hundred ordinary hands. Their heads banged; they saw stars — and nothing else.
Doc grasped each of these unconscious warriors by the woven leather mantles they wore secured about their necks. He slung them, blue girdles flopping, into the midst of the other attackers. A full half dozen of these went down, mightily bruised and bewildered. The others milled, all tangled up with each other.
Suddenly Doc was among them! Not satisfied with overpowering the four, he pitched into the whole crew. Terrific blows came from his flashing fists. Red-fingered men began to drop in the milling, fighting mob. Piercing yells of pain arose.
As one, the mob of warriors fled! They couldn't fight this bronze being who moved too quickly for them to land a single blow.
Morning Breeze, tremendously chagrined, spun to flee with his satellites. One leap, two, he took. Then Doc, with a great spring, had him by the neck.
Doc took Morning Breeze's sacred knife, his only weapon, away from him.
'Have you some place we can lock him up so he won't give more trouble?' Doc asked King Chaac. Doc was not even breathing heavily.
The Mayan sovereign was both amazed and highly elated. 'I have!' he declared.
To one side, entrancing Princess Monja of the Mayans had been an admiring observer. Her dark eyes, as
