Catching up his rifle, Frank started on a run in the direction taken by the guide.

Down into the valley he went, his eyes wide open. Suddenly, a short distance before him, there was a hissing, rushing roar, and a column of mud and water shot into the air.

There were the mud geysers Old Rocks had started out to look for.

Toward the geyser hurried Frank, still looking for his companion.

Before the column of mud and water had ceased shooting into the air, Frank came upon a startling spectacle.

Not far from the geysers Old Rocks was engaged in a hand-to-hand encounter with a huge grizzly bear!

On the ground near by lay the body of another bear, telling how accurate had been the guide's first shot.

The guide was using his bowie knife, which was already stained with blood to the hilt.

Frank did not hesitate about rushing straight toward the battling man and beast, and Old Rocks saw him coming.

"Keerful, boy!" panted the man; "keerful with thet thar rifle! Don't shoot yere, fer yer might bore me."

"I won't hit you," promised Frank. "I will shoot the bear."

"You don't know whar ter put yer lead, an' yer might fire a dozen bullets inter this varmint 'thout finishin' him."

It was evident that the old man was badly winded.

Thus far he had avoided the bear's hug, but he could not hold out long.

Barely had he uttered the last words when, with a sudden blow of one paw, the grizzly struck him to the ground.

Frank rushed in, seeing the monster settle on all fours over Old Rocks.

"I'll fix him!" grated the boy, as he thrust the muzzle of his rifle almost against bruin's head and pulled the trigger.

For the first time on record the weapon missed fire.

With a fierce growl, the bear whirled and knocked the rifle out of Frank's grasp.

In a dazed manner, Old Rocks saw everything.

"Ther kid's a goner!" thought the guide. "We're both done fer!"

Out Frank snapped a revolver, and then, taking a step toward the bear, he fired five bullets into the creature in marvelously rapid succession.

A roar came from the bear's throat, and the beast reared on its hind feet, its jaws dripping blood and foam, and rushed upon the dauntless boy.

Frank flung aside the revolver, just as Rocks struggled to a sitting posture, thickly crying:

"Run, kid! run fer yer life!"

"Not much!" came through Frank's set teeth. "Think I'd run and leave you to the bear! I guess not!"

"Dog my cats!" murmured the guide, weakly.

The bear, dripping blood from its many wounds, still fierce as a raging tiger, came at Frank. The boy dodged, managed to avoid the rush, and gave the beast a wicked stab with the knife.

"Dog my cats!" murmured the dazed guide once more.

Frank Merriwell's face bore a look of fearless determination, and he was ready for the bear to charge again.

It came.

Frank tried to repeat the trick, slipped a bit, saw he could not escape, and then met the formidable beast.

"Now he is a goner!" gurgled Old Rocks, faintly.

With outstretched paws the bear closed in.

Frank saw he was not going to be able to escape the hug, and he placed the haft of the knife against his own breast, with the point directed toward the bear.

The grizzly folded Frank in his embrace, crushing the lad against his s.h.a.ggy breast, and, in this way, the creature drove the knife home to its own heart.

Uttering a great groan, it relaxed its hold, dropped on all fours, hung its head, and then sunk in a heap upon the ground, dying.

Frank felt as if his ribs had been crushed, and he was covered with blood, but he had conquered.

Old Rocks was so dazed that he sat on the ground, staring at the "tenderfoot kid," and faintly gasping:

"Dog my cats!"

Frank flung the knife to the ground, and then sat down, panting, in a desperate endeavor to get a full breath.

Old Rocks got up very slowly, stood looking at the dead bear some moments, and then looked at the boy.

"This beats me!" he grunted. "Whoever heard o' a tenderfut doin' sech a thing! An' he didn't seem ter be scart a tall!"

Then he came nearer Frank, at whom he still stared.

"It ain't a mistake, none whatever. This yar kid done it, and he done it in great shape! Say, youngster."

"What?"

"I wants ter 'polergize."

"What for?"

"Fer sayin' tenderfeet never has sand. I'll take it all back. You've got sand enough fer anything, you hev! Do you know whut you done? Wa-al, a grizzly is harder ter kill then a hull tribe o' Injuns! I wuz dead lucky ter kill t'other one by a chance shot, an' I'd never done it ef I hedn't been so nigh ther muzzle o' my rifle wuz right up ag'in' ther varmint.

You worked an old hunter's trick on him. Thet fust jab you gave ther whelp kinder spruced him up, an' he wuz ready ter crush ther stuffin'

outer yer. By holdin' ther knife ez yer did, yer made him kill hisself.

Guv us yer hand! I'll swar by you through thick and thin!"