But for Gale the marvel of that endless period of watching was the purpose of the bandit Rojas.  He had now no weapon.  Gale’s glass made this fact plain.  There was death behind him, death below him, death before him, and though he could not have known it, death above him.  He never faltered—­never made a misstep upon the narrow, flinty trail.  When he reached the lower end of the level ledge Gale’s poignant doubt became a certainty.  Rojas had seen Mercedes.  It was incredible, yet Gale believed it.  Then, his heart clamped as in an icy vise, Gale threw forward the Remington, and sinking on one knee, began to shoot.  He emptied the magazine.  Puffs of dust near Rojas did not even make him turn.

As Gale began to reload he was horror-stricken by a low cry from Thorne.  The cavalryman had recovered consciousness.  He was half raised, pointing with shaking hand at the opposite ledge.  His distended eyes were riveted upon Rojas.  He was trying to utter speech that would not come.

Gale wheeled, rigid now, steeling himself to one last forlorn hope —­that Mercedes could defend herself.  She had a gun.  He doubted not at all that she would use it.  But, remembering her terror of this savage, he feared for her.

Rojas reached the level of the ledge.  He halted.  He crouched.  It was the act of a panther.  Manifestly he saw Mercedes within the cave.  Then faint shots patted the air, broke in quick echo.  Rojas went down as if struck a heavy blow.  He was hit.  But even as Gale yelled in sheer madness the bandit leaped erect.  He seemed too quick, too supple to be badly wounded.  A slight, dark figure flashed out of the cave.  Mercedes!  She backed against the wall.  Gale saw a puff of white—­heard a report.  But the bandit lunged at her.  Mercedes ran, not to try to pass him, but straight for the precipice.  Her intention was plain.  But Rojas oustripped her, even as she reached the verge.  Then a piercing scream pealed across the crater—­a scream of despair.

Gale closed his eyes.  He could not bear to see more.

Thorne echoed Mercedes’s scream.  Gale looked round just in time to leap and catch the cavalryman as he staggered, apparently for the steep slope.  And then, as Gale dragged him back, both fell.  Gale saved his friend, but he plunged into a choya.  He drew his hands away full of the great glistening cones of thorns.

“For God’s sake, Gale, shoot!  Shoot!  Kill her!  Kill her!...Can’t —­you—­see-Rojas—­”

Thorne fainted.

Gale, stunned for the instant, stood with uplifted hands, and gazed from Thorne across the crater.  Rojas had not killed Mercedes.  He was overpowering her.  His actions seemed slow, wearing, purposeful.  Hers were violent.  Like a trapped she-wolf, Mercedes was fighting.  She tore, struggled, flung herself.

Rojas’s intention was terribly plain.

In agony now, both mental and physical, cold and sick and weak, Gale gripped his rifle and aimed at the struggling forms on the ledge.  He pulled the trigger.  The bullet struck up a cloud of red dust close to the struggling couple.  Again Gale fired, hoping to hit Rojas, praying to kill Mercedes.  The bullet struck high.  A third—­fourth—­fifth time the Remington spoke—­in vain!  The rifle fell from Gale’s racked hands.