After the green man had swung up beside them without mishap, the three climbed the ropes to the scaffolding above and then lowered themselves down to the ground beside the pit.

"Thank Issus," breathed the girl as they sat down to regain their breaths. Her beautiful head was cushioned upon Carter's shoulder, and he stroked her lovely black hair reassuringly.

Presently the earthman rose to his feet. Tars Tarkas had motioned him across the arena.

"There are some malagors left inside here," Tars Tarkas called from the entrance to the cavern inside the crater from where had come Pew mogel's mounts.

"Good!" exclaimed Carter. "There may be a chance yet to reach and help Helium."

A moment later they had caught two of the birds and had risen over the ancient city of Korvas.

They spotted their planes on the outskirts of the city where they had left them the night they were tricked into being captured by Pew Mogel.

But to their disappointment, the controls had been destroyed irreparably, so they were forced to continue their journey on the backs of the malagors.

However, the malagors proved speedy mounts. By noon the next day the trio had reached the City of Thark, inhabited by a hundred thousand green warriors over whom Tars Tarkas ruled.

Gathering the warriors together in the marketplace, Tars Tarkas and John Carter explained the peril that confronted Helium and asked for their support in marching to their allies' aid.

As one man, the mighty warriors shouted their approval. The next day dawned upon a long caravan of thoat-mounted soldiers streaming out from the city gates towards Helium.

A messenger was sent on a malagor to the Toonolian Marshes in an attempt to locate Kantos Kan and urge him to return home with his fleet to aid in the defense of Helium.

Tars Tarkas had abandoned his malagor to this messenger, in favour of a thoat upom which he rode at the head of his warriors. Directly above him, mounted on the other malagor rode Dejah Thoris and John Carter.

Chapter 9 ATTACK ON HELIUM

John Carter and Dejah Thoris, mounted upon their malagor, were scouting far ahead of the main column of advancing warriors when they first came in sight of the besieged City of Helium.

It was bright moonlight. The princess voiced a little, disappointed cry when she looked out across the spacious valley towards Helium. Her grandfather's city was completely surrounded by the besieging troops of Pew Mogel.

"My poor city!" The girl was crying softly, for in the bright moonlight below could be easily discerned the terrific gap in the ramparts and the many crushed and shattered buildings of the beautiful metropolis.

John Carter telepathically commanded the malagor to land upon a high peak in the mountains overlooking the Valley of Helium.

"Listen," cautioned John Carter. Pew Mogel's light entrenched cannon and small arms were commencing to open fire again by moonlight. "They are getting ready for an air attack."

Suddenly, from behind the two foothills between the valley and the towering peaks, there rose the vast, flying army of Pew Mogel.

"They are closing in from all sides," Dejah Thoris cried.

The great winged creatures and their formidable ape riders were swooping down relentlessly upon the city. Only a few of Helium's airships rose to give battle.

"Kantos Kan must have taken nearly all Helium's fleet with him," the earthman remarked. "I am surprised Helium has withstood the attack as long as this."

"You should know my people by now, John Carter," replied the princess.

"The infantry and anti-aircraft fire entrenched in Helium are doing well," Carter replied. "See those birds plummet to the ground."

"They can't hold out much longer, though," the girl replied. "Those apes are dropping bombs squarely into the city, as they swoop over, wave after wave of them—oh, John Carter, what can we do?"

John Carter's old fighting smile, usually present at times of personal danger, had given way to a stern, grave expression.

He saw below him the oldest and most powerful city on Mars being conquered by Pew Mogel's forces. Armed with Helium's vast resources, the synthetic man would go forth and conquer all the civilized nations on Mars.

Fifty thousand years of Martian learning and culture wrecked by a power-mad maniac, himself the synthetic product of civilized man!

"Is there nothing we can do to stop him, John Carter?" came the girl's repeated question.

"Very little, I'm afraid, my princess," he replied sadly, "All we can do is station Tars Tarkas's green warriors at an advantageous point in preparation for the counterattack and trust to fate that our messenger reached Kantos Kan in time that he may return and aid us."

"Without supporting aircraft, our green warriors, heroic fighters that they are, can do little against Pew Mogel's superior numbers in the air."

When John Carter and Dejah Thoris returned to Tars Tarkas, they reported what they had seen.

The great Thark agreed that his warriors could avail but little in a direct attack against Pew Mogel's air force. It was decided that half their troops be concentrated at one point and at dawn attempt to rush into the City.

The remaining half of the warriors would scatter into the mountains in smaller groups and engage the enemy in guerilla warfare.

Thus they hoped to forestall the fate of Helium until Kantos Kan returned with his fleet of speedy air fighters.

"Helium's fleet of trim, metal fighting craft will furnish Pew Mogel's feathered bird brigade a worthy enemy," remarked Tars Takas.

"Provided, of course," added John Carter, "Kantos Kan's fleet reaches Helium before Pew Mogel has entrenched himself in the City and returned his own anti-aircraft guns upon them."

All that night in the mountains, under cover of semi-darkness, John Carter and Tars Tarkas reorganized and restationed their troops. By dawn, all was ready.

John Carter and Tars Tarkas would lead the advance half of the Tharks in a wild rush toward the gates of Helium, the other half would remain behind, covering their comrades' assault with long range rifles.

Much against the earthman's will, Dejah Thoris insisted she would ride into the City beside him upon their malagor.

It was just commencing to grow brighter.

"Prepare to charge," John Carter ordered. Tars Tarkas passed the word down and across by his orderly to his unit commanders.

"Prepare to charge! Prepare to charge!" echoed down and across the battalions of magnificent, four-armed green fighters astride their eight-legged, massive, restless Throats.

The minutes dragged by as the troop lines swung around. Steel swords were drawn from scabbards. Hammers, on short deadly ray-pistols, clicked back as they cocked over saddle pommels.

John Carter looked around at the girl sitting so straight and steady behind him.

"You are very brave, my princess," he said.

"It's easy to be brave," she replied, "when I'm so close to the greatest warrior on Mars."

"Charge!" came John Carter's terse, sudden order.

Down the mountain and across the plain toward Helium streaked the savage hoard of Tharks. Out ahead raced Tars Tarkas, his sword held high.

Far ahead and above, on speedy wings, streaked the malagor bearing John Carter and the Princess of Helium.

"John Carter, thank Issus!" Dejah Thoris cried in relief and pointed toward the far mountain skyline.

"The Helium fleet has returned," shouted John Carter. "Our messenger reached Kantos Kan in time!" Over the mountains, with flying banners streaming, sailed the mighty Helium fleet.

There was a moment's silence in the entrenched guns of the enemy. They had seen the charging Tharks and the Helium fleet simultaneously.

A great cry of triumph rose from the ranks of the charging warriors at the sight of the Helium fleet streaking to their aid.

"Listen," cried Dejah Thoris to Carter, "the bells of Helium are tolling our victory song!" then it seemed as though all of Pew Mogel's guns broke loose at once and from behind the protecting hills rose his flying legions of winged malagors. Upon their backs rode the white apes with men's brains.

Down upon the legions of Tharks came wave after wave of Pew Mogel's feathered squadrons. In true blitzkrieg fashion, the birds would swoop down just out of sword's reach over the green warriors. As each bird pulled out of its dive, the ape on its back would empty its death-dealing atomgun into the mass of warriors beneath.

The carnage was terrific. Only after Tars Tarkas and John Carter had led their warriors into the first lines of entrenched apes did the Tharks find an enemy with whom they could fight effectively.

Here, the four-armed green soldiers of Thark fought gloriously against the great white apes of Pew Mogel's ghastly legions.

But never for a second did the horrible death-dealing squadrons cease their attacks from above. Like angry hornets, the thousands dove, killed, climbed again, always killing.

John Carter masterfully controlled his frightened bird while he issued orders and directed attacks from his vantage point immediately above the center of battle.

Bravely, efficiently, the Princess of Helium protected her chieftain against countless side and rear attacks from the air. The barrel of her radium pistol was red-hot with constant firing and many were the charging birds and shrieking apes she sent catapulting into the melee below.

Suddenly a hoarse shout rose again from Pew Mogel's legions on ground and in the air.

"What is it, my chieftain?" cried the girl. "Why are the enemy shouting in triumph?"

John Carter looked toward the advancing ships now over the mountains only half a mile away, then his blood ran cold.

"The giant—Joog the giant!"

The creature had risen up from behind the shelter of a low hill, as the ships approached above him. The giant grasped a huge tree trunk in his mighty hand.

Even from where they were, John Carter could discern the head of a man sitting in an armor-enclosed, steel howdah strapped to the top of Joog's helmet.

From the giant's lips there suddenly issued a thunderous, shrieking roar that echoed in the mountains and across the plain.

Then he clambered swiftly to the top of a small hill. Before the astonished Heliumites could swerve their speeding craft, the giant struck out mightily with the great tree trunk.

The great, synthetic muscles of Pew Mogel's giant swung the huge weapon full into the advancing craft.

The vanguard of twenty ships, the pride of Helium's airfleet met the blow head-on-went smashing and shattering against the mountain-side, carrying their crews to swift, crushing death!

Chapter 10 TWO THOUSAND PARACHUTES

Kantos Kan's flagship narrowly escaped annihilation at the first blow of the giant.