The Danites were marching their captives out to execution!

In a very few moments the professor and the boy were tied to the death-posts.

Uric Dugan directed the movements of the Danites.

"Where is Miskel?" hoa.r.s.ely breathed Frank. "Will she do nothing to prevent this?"

"She has done all she could," muttered Old Solitary. "It is probable she was not aware the tribunal was in progress. She will be prevented from interfering now."

And now six men, with rifles in their hands, formed a line in front of the prisoners.

Everything was done with startling swiftness.

Frank Merriwell was trembling with eagerness and excitement, and he appealed to Old Solitary:

"Are we to remain inactive and see this frightful deed? Are we to do nothing now that we are here?"

"We will do what we can," declared the strange man. "The time has come for Dugan's career to end! I feel that I must strike. He shall never give the fatal signal!"

The man lifted his old rifle, and the hammer clicked as he c.o.c.ked it.

Dugan stepped forth to give the signal, and his harsh voice rang out distinctly:

"Ready!"

The firing squad lifted their rifles.

"Take aim!"

The fatal moment was at hand.

The b.u.t.t of Old Solitary's rifle came to the man's shoulder. He was resting on one knee, and the weapon was held as steady as the hills.

"One!" counted Dugan.

It was the last word he ever uttered, for a spout of flame leaped from the muzzle of Old Solitary's weapon, and the bullet sped on its fatal mission.

Without a cry or a groan, Dugan flung up his hands and plunged headlong upon his face.

There was a wild shriek, and the form of a girl rushed into the firelight. Down beside the fallen man she dropped, lifting his head and staring wildly into his face.

It was Miskel, but she could not save her wicked father, for the aim of Old Solitary had been accurate.

The Danites were thrown into the greatest confusion, and Frank Merriwell held back no longer.

"Come on, Barney!" he shouted.

"Oi'm wid yez!" a.s.sured the undaunted Irish lad.

Forward they rushed, each firing a shot as they did so, and adding to the dismay of the Danites.

Straight up to Professor Scotch ran Frank, and, with one slash of a sharp knife he had drawn, he released the man.

Barney did the same thing for Walter Clyde, and the two were set at liberty before the Danites realized what was happening. Then bullets began to whistle around them.

At that moment a wild, strange cry cut the night air, filling the hearts of the Danites with the utmost terror.

It was the war cry of the Navajoes!

A hundred dusky forms seemed to materialize from the darkness, and a hundred savage warriors, deadly enemies of the Danites, came charging into the camp.

Old Solitary had rushed to the side of Uric Dugan, into whose face he glared, as he cried:

"Look, Dugan, look! You robbed me of reason, of memory, of everything I held dear; but I have been avenged, for it was my hand that laid you low!"

"He is dead!" screamed Miskel, and she fainted on her father's body.

"Yes, he is dead!" said the avenger, in a half-regretful tone. "And he never knew who killed him."

Then he suddenly caught up the girl and rushed away into the darkness, with her flung over his shoulder.

How Frank and his companions escaped from that spot without falling before the Danites or the savages they scarcely knew. A dozen times they fancied all was lost. They emptied their weapons, they struck down every one who blocked their way, and they finally succeeded in getting out of the pocket.

That they did so at all was due to the fact that the Navajoes, who had surprised and overcome the guard in the pa.s.s, believed they held the only exit from the canyon, which made it impossible for any one to get away, even though they might escape temporarily. If two or three were to escape for the time, the Indians felt that it was impossible for them to get away entirely.

But Professor Septemas Scudmore, with his air ship, was in the canyon, and the boys, half lugging the exhausted Professor Scotch, found him waiting for them, greatly alarmed and excited by the sounds of the battle.

"What does it mean?" cried the lank professor, as the party rushed up.

"What is all that shooting and yelling?"

"There is no time to explain now," said Frank. "Get in, everybody, and let's get out of this infernal place as soon as we can! There is not a moment to lose."

"I am bewildered," declared Scudmore. "A moment ago an old man with white hair and beard rushed up to me, bearing a girl in his arms. She had fainted, and he thrust her into the car, telling me to wait for you, and take her away with us."

"It was Old Solitary, and the girl must be Miskel. Is she in the car now?"

"Yes."

"And the man?"

"He is gone."

"It was Old Solitary, sure enough, and he will be able to hide from the savages. We cannot wait for him."

"The _Eagle_ would not carry so many, even if we could wait. I have her inflated, and she is tied down. Get in, get in! We'll throw out every bit of ballast, and make the attempt to rise out of the canyon. It may be a failure, but I think it will succeed, if we can get high enough to strike the strong wind which is blowing above us. We can try."

They got into the car, and the bags of ballast were tossed overboard.

Then the ropes were cut, and the air ship rose slowly with its heavy burden.