charge broke and the riflemen galloped away to reload their weapons, Dick gave the signal to retreat to the second line of defense.

The Taharans fell back, keeping close to the ground and taking shelter at every bush and boulder.

So far the battle had been in their favor. The black-bearded ruffians had been repulsed with dead and wounded, while the Taharans had escaped without loss of a man.

Of course, luck could not favor them always. The raiders had withdrawn to take counsel with Abdul and that ferocious chieftain swore by the beard of the Prophet that he would show no mercy to the "infidel dogs" who had dared to resist him. His hawk eyes stared furiously at the cliffs, then at the boulders, behind each of which lurked a bowman.

"We will not make another charge!" he ordered. "This time each horseman will ride warily, rifle ready for action. Make a detour! Ride to one side of the rocks and try to pick off the archers one by one."

Suli, who rode beside Abdul, searched the horizon with black, angry eyes.

"Where is Slythe?" he muttered. "The winged warrior has failed us!"

Abdul heard him and vented a hearty curse upon the missing airman.

"He has led us into a trap! May he perish and the dogs devour him!"

"He did not warn us that the savages of this tribe would fight like demons!" put in a wounded Arab, knotting a strip of linen about his bleeding arm.

"If we had known that they could fight like tigers, we would have raided them by night when they slept," growled Abdul. "Now it is too late for a surprise or a parley. We must fight it through."

"And first of all we must have water for ourselves and our horses!" grumbled Suli.

"Yes, by the Prophet! First we shall capture the spring. But not by storm! Ride warily and pick off the dogs one at a time!"

Carefully the troop approached and this time Dick used another strategy. As an Arab rider would approach a rock, a Taharan would break and run back to another shelter. But when the Arab chased him, firing his rifle, a second tribesman still hiding behind the rock would take a shot at the Arab at close range.

So keen and clever were the Taharan archers, that few arrows missed. But the tribesmen were not so fortunate as to go unscathed through the second attack. More than one was dropped by an Arab bullet, some to rise no more.

Dick Oakwood directed the running fight, giving orders to Raal, who shouted them to his men in a voice that rang out like the bellowing of a bull. Though he might be frightened at evil magic and things that he did not understand, Raal was brave as a lion when it came to battle.

Dan Carter had stayed in the rear according to Dick's orders until the thrill of watching the fight got his nerves on edge with excitement. Then, armed with a bow and a quiver of arrows, he ran from one shelter to another until he was among the fighting men. At the last rock where he took refuge, a Taharan archer was already hidden, driving his arrows to the mark every time an Arab rider came within range.

Dan saw it was Kurt, one of Dick's most trusted henchmen, and with a word of encouragement, the boy took up his position on the other side of the big rock.

"Let 'em have it!" said Dan.

"Let 'em have it!" Kurt repeated and both marksmen let fly at a Bedouin, mounted on a splendid gray horse that came charging toward the rock.

The arrows whizzed through the air, but the rider was on guard and dropped from his saddle, hanging to the side of his horse and protected by its body.

Then before the archers could shoot again he was right beside the rock and slashing out with his curving sword, struck at Kurt with a blow that laid open the tribesman's shoulder.

Dan was ready with his second arrow by that time and let drive a dart that caught the Arab in the throat and dropped him to the ground. The horse galloped on, while Kurt and Dan ran back toward the cliffs, for now other Arabs were close by and their position was too hot to keep.

"Allah il allah!" shouted the raiders, galloping to head off the fugitives.

"Slay the dogs of unbelievers!"

Their howls of fury rose shrill and high amid the rattling of rifle shots, the whinnying of horses and the war cry of the tribesmen, "Tahara, hal! Tahara!"

Dan was racing for life, when he saw that Kurt was lagging. Loss of blood from the gash on his shoulder had weakened the Taharan warrior and it seemed as if he might fall from exhaustion, so Dan forgot his own danger to help Kurt escape.

The Arab pursuers saw that the two enemies were having a hard time to get away and let out yells of triumph.

"Allah! Down with the unbelievers!"

A couple of horsemen sped toward the fugitives and their rifles sent the echoes flying back from the cliffs, though the bullets missed their mark and sent puffs of dust from the ground to either side.

"Run, Kurt! Run for your life!" gasped Dan Carter.

"Leave me! I grow weak, but I can die like a man," answered Kurt, brave to the last.

"You're not going to die!" said Dan. "Here, put your weight on my shoulder. I'll help you!"

Their situation was desperate. Behind them came the two Arabs, tugging at their scimiters to release them from the scabbards and eager to cut the fugitives to bits.

Before them raced the riderless horse, zig-zagging to avoid the tribesmen who yelled and waved their arms at it. The animal was trying to reach the spring, for it was eager for water after the long trip.

In desperation Dan dragged his wounded comrade back of a small boulder and took up his position beside him. His bow was already sending a swift arrow at the foremost rider when a yell behind him caused him to look over his shoulder.

Dick Oakwood had seen the danger that his friends were in and acted promptly. He had snatched a coiled rope, carried by one of the tribesmen, and now ran toward the riderless horse, loosening the loop as he ran. Then as the animal swerved and passed, not far away, Dick whirled the lariat, sent it flying and braced himself for the shock.

It was a good throw.

The loop settled around the animal's neck and as Dick put his weight against it the noose tightened and the horse came down, half choked and terrified.

Before the animal could scramble to its feet, Dick was in the saddle, loosening the lariat and seizing the reins. A moment later with a new rider on its back, the Arab horse was heading back to where Dan and Kurt were standing off the Bedouin attackers.

CHAPTER IV

THE BATTLE RAGES

"Hold 'em, Dan, I'm with you!"

Dan heard the cry, and at the same moment saw one of his attackers drop with an arrow through the chest.

Dick Oakwood was at home in the saddle and now he drove furiously at the remaining Arab, who was almost on top of Dan with scimiter upraised ready to deliver a fatal blow.

Dan reached for an arrow. But his quiver was empty!

The boy's only weapon was a flint knife, and that was almost useless in fighting a foe armed with a razor-edged sword.

Dan gave a despairing shout for help as he saw Dick Oakwood galloping toward him, and dodged the blow of the scimiter, missing it by such a close margin that the steel whizzed past his ear with a swishing sound.

"Attaboy, Dan!"

At Dick's cry of encouragement, Dan saw the Arab suddenly reel back in the saddle, fling up both arms and slump to the ground in a heap. Dick had no weapon but the rope, but he had learned to use the lariat as well as any cowboy.

The loop had dropped over the Bedouin's body, and as Dick wheeled his horse the Arab was dragged from the saddle and pulled across the desert until he was stunned and helpless.

At this, Dan let out a great shout of relief.

"Hooray, Dick! Fine work!" and he started hot-foot for safety, helping the wounded Kurt as best he could.

They were far from safe, however,