So much young Blacklock noted at the moment of uprushing. In the next breath he had wrapped the mackintoshed bomb-firer in a wrestler's hug from behind, and the knife raised to be driven into Ballard's back clattered upon the stones of the path. There was a gasping oath in a strange tongue, a fierce struggle on the part of the garroted one to turn and face his new a.s.sailant, and then the collegian, with his chin burrowing between the shoulder-blades of his man, heard swift footsteps approaching and a deep-toned, musical voice booming out a sharp command: "Manuel! you grand scoundrel!--drop that thah gun, suh!"

Something else, also metallic, and weightier than the knife, clicked upon the stones; whereupon Blacklock loosed his strangler's grip and stepped back. Ballard stooped to pick up the knife and the pistol.

Wingfield, who had been the colonel's second in the race along the hazardous mine path, drew aside; and master and man were left facing each other.

The Mexican straightened up and folded his arms. He was breathing hard from the effect of Blacklock's gripping hug, but his dark face was as impa.s.sive as an Indian's. The white-haired King of Arcadia turned to Ballard, and the mellow voice broke a little.

"Mistuh-uh Ballard, you, suh, are a Kentuckian, of a race that knows to the fullest extent the meaning of henchman loyalty. You shall say what is to be done with this po' villain of mine. By his own confession, made to me this afte'noon, he is a cutthroat and an a.s.sa.s.sin. Undeh a mistaken idea of loyalty to me"--the deep voice grew more tremulous at this--"undeh a mistaken idea of loyalty to me, suh, he has been fighting in his own peculiah fashion what he conceived to be my battle with the Arcadia Company. Without compunction, without remo'se, he has taken nearly a score of human lives since the day when he killed the man Braithwaite and flung his body into the riveh. Am I making it cleah to you, Mistuh Ballard?"

How he managed to convey his sense of entire comprehension, Ballard scarcely knew. One thought was submerging all others under a mounting wave of triumphant joy: Colonel Adam, the father of the princess of heart's delight, was neither a devil in human guise nor a homicidal madman. Elsa's trouble was a phantom appeased; it had vanished like the dew on a summer morning.

"I thank you, suh," was the courtly acknowledgment; and then the deep voice continued, with an added note of emotion. "I am not pleading for the murderer, but for my po' liegeman who knew no law of G.o.d or man higheh than what he mistakenly took to be his masteh's desiah. How long all this would have continued, if I hadn't suhprised him in the ve'y act of trying to kill you as you were lowering that thah stop-gate to-day, we shall neveh know. But the entiah matteh lies heavy on my conscience, suh. I ought to have suspected the true sou'ce of all the mysterious tragedies long ago; I should have suspected it if I hadn't been chin-deep myself, suh, in a similah pool of animosity against Mr. Pelham and his fellow-robbehs. What will you do with this po' scoundrel of mine, Mistuh Ballard?"

"Nothing, at present," said Ballard, gravely, "or nothing more than to ask him a question or two." He turned upon the Mexican, who was still standing statue-like with his back to the low cliff of the path ledge.

"Did you kill Macpherson?--as well as Braithwaite and Sanderson?"

"I kill-a dem all," was the cool reply. "You say--he all say--'I make-a da dam.' I'll say: '_Caramba!_ You _no_ make-a da dam w'at da Colonel no want for you to make.' Da.s.s all."

"So it was you who hit Bromley on the head and knocked him into the canyon?"

The statuesque foreman showed his teeth. "Dat was one bad _mees_take.

I'll been try for knock _you_ on da haid, dat time, for sure, Senor Ballar'."

"And you were wearing that rain-coat when you did it?"

The Mexican nodded. "I'll wear heem h-always w'en da sun gone down--same like-a da Colonel."

"Also, you were wearing it that other night, when you heaved a stone down on my office roof?"

Another nod.

"But on the night when you scared Hoskins and made him double up his train on Dead Man's Curve, you didn't wear it; you wore a shooting-coat and a cap like the one Braithwaite used to wear."

The posing statue laughed hardily. "Dat was one--w'at you call heem?--one beeg joke. I'll been like to make dat 'Oskins break hees h'own neck, _si_: hees talk too much 'bout da man w'at drown' heself."

"And the Carson business: you were mixed up in that, too?"

"Dat was one _mees_take, al-so; one ver' beeg _mees_take. I'll hire dat dam'-fool Carson to shoot da ditch. I t'ink you and da beeg h-Irishman take-a da trail and Carson keel you. Carson, he'll take-a da money, and make for leetle scheme to steal cattle. Som' day I keel heem for dat."

"Not in this world," cut in Ballard, briefly. "You're out of the game, from this on." And then, determined to be at the bottom of the final mystery: "You played the spy on Mr. Wingfield, Bromley, Blacklock and me one afternoon when we were talking about these deviltries. Afterward, you went up to Castle 'Cadia. That evening Mr. Wingfield nearly lost his life. Did you have a hand in that?"

Again the Mexican laughed. "Senor Wingfiel' he is know too moch. Som'

day he is make me ver' sorry for myself. So I'll hide be'ind dat fornace, and give heem one leetle push, so"--with the appropriate gesture.

"That is all," said Ballard, curtly. And then to the colonel: "I think we'd better be moving over to the other side. The ladies will be anxious. Jerry, take that fellow on ahead of you, and see that he doesn't get away. I'm sorry for you, Colonel Craigmiles; and that is no empty form of words. As you have said, I am a Kentuckian, and I do know what loyalty--even mistaken loyalty--is worth. My own grudge is nothing; I haven't any. But there are other lives to answer for. Am I right?"

"You are quite right, suh; quite right," was the sober rejoinder; and then Blacklock said "_Vamos!_" to his prisoner, airing his one word of Spanish, and in single file the five men crossed on the dam to the mesa side of the rising lake where Bigelow, with Elsa and Miss Cantrell and a lately awakened Mrs. Van Bryck, were waiting. At the rea.s.sembling, Ballard cut the colonel's daughter out of the storm of eager questionings swiftly, masterfully.

"You were wrong--we were all wrong," he whispered joyously. "The man whom you saw, the man who has done it all in your father's absolute and utter ignorance of what was going on, is Manuel. He has confessed; first to his master, and just now to all of us. Your father is as sane as he is blameless. There is no obstacle now for either of us. I shall resign to-morrow morning, and----"

It was the colonel's call that interrupted.

"One moment, Mistuh Ballard, if you please, suh. Are there any of youh ditch camps at present in the riveh valley below heah?"

Ballard shook his head. "Not now; they are all on the high land." Then, remembering Bromley's report of the empty ranch headquarters and corrals: "You think there is danger?"

"I don't think, suh: I _know_. Look thah," waving an arm toward the dissolving mine dump on the opposing slope; "when the wateh reaches that tunnel and finds its way behind the bulkhead, Mistuh Ballard, youh dam's gone--doomed as surely as that sinful world that wouldn't listen to Preachuh Noah!"

"But, Colonel--you can't know positively!"

"I do, suh. And Mistuh Pelham knows quite as well as I do. You may have noticed that we have no pumping machinery oveh yondeh, Mistuh Ballard: _That is because the mine drains out into youh pot-hole below the dam!_"

"Heavens and earth!" e.j.a.c.u.l.a.t.ed Ballard, aghast at the possibilities laid bare in this single explanatory sentence. "And you say that Mr.

Pelham knows this?"

"He has known it all along. I deemed it my neighbo'ly duty to inform him when we opened the lower level in the mine. But he won't be the loseh; no, suh; not Mistuh Howard Pelham. It'll be those po' sheep that he brought up here to-day to prepare them for the shearing--if the riveh gives him time to make the turn."

"The danger is immediate, then?" said Bigelow.

The white-haired King of Arcadia was standing on the brink of the mesa cliff, a stark figure in the white moonlight, with his hand at his ear.

"Hark, gentlemen!" he commanded; and then: "Youh ears are all youngeh than mine. What do you heah?"

It was Ballard who replied: "The wind is rising on the range; I can hear it singing in the pines."

"No, suh; that isn't the wind--it's wateh; torrents and oceans of it.

There have been great and phenomenal storms up in the basin all day; storms and cloud-bursts. See thah!"

A rippling wave a foot high came sweeping down the gla.s.sy surface of the reservoir lake, crowding and rioting until it doubled its depth in rushing into the foothill canyon. Pa.s.sing the mine, it swept away other tons of the dump; and an instant later the water at the feet of the onlookers lifted like the heave of a great ground-swell--lifted, but did not subside.

Ballard's square jaw was out-thrust. "We did not build for any such brutal tests as this," he muttered. "Another surge like that----"

"It is coming!" cried Elsa. "The power dam in the upper canyon is gone!"

and the sharer of the single Cantrell Christian name shrieked and took shelter under Bigelow's arm.

Far up the moon-silvered expanse of the lake a black line was advancing at railway speed. It was like the ominous flattening of the sea before a hurricane; but the chief terror of it lay in the peaceful surroundings.

No cloud flecked the sky; no breath of air was stirring; the calm of the matchless summer night was unbroken, save by the surf-like murmur of the great wave as it rose high and still higher in the narrowing raceway.

Instinctively Ballard put his arm about Elsa and drew her back from the cliff's edge. There could be no chance of danger for the group looking on from the top of the high mesa; yet the commanding roar of the menace was irresistible.

When the wave entered the wedge-shaped upper end of the Elbow it was a foam-crested wall ten feet high, advancing with the black-arched front of a tidal billow, mighty, terrifying, the cold breath of it blowing like a chill wind from the underworld upon the group of watchers. In its onrush the remains of the mine dump melted and vanished, and the heavy bulkhead timbering at the mouth of the workings was torn away, to be hurled, with other tons of floating debris, against the back-wall of the dam.

Knowing all the conditions, Ballard thought the masonry would never withstand the hammer-blow impact of the wreck-laden billow. Yet it stood, apparently undamaged, even after the splintered ma.s.s of wreckage, tossed high on the crest of the wave, had leaped the coping course to plunge thundering into the ravine below. The great wall was like some ma.s.sive fortification reared to endure such shocks; and Elsa, facing the terrific spectacle beside her lover, like a reincarnation of one of the battle-maidens, gave him his rightful meed of praise.

"You builded well--you and the others!" she cried. "It will not break!"

But even as she spoke, the forces that sap and destroy were at work.

There was a hoa.r.s.e groaning from the underground caverns of the zirconium mine--sounds as of a volcano in travail. The wave retreated for a little s.p.a.ce, and the white line of the coping showed bare and unbroken in the moonlight. Silence, the deafening silence which follows the thunderclap, succeeded to the clamour of the waters, and this in turn gave place to a curious gurgling roar as of some gigantic vessel emptying itself through an orifice in its bottom.

The white-haired king was nearest to the brink of peril. At the gurgling roar he turned with arms outspread and swept the onlooking group, augmented now by the men from Garou's cook camp, back and away from the dam-head. Out of the torrent-worn pit in the lower ravine a great jet of water was spurting intermittently, like the blood from a severed artery.

"That is the end!" groaned Ballard, turning away from the death grapple between his work and the blind giant of the Boiling Water; and just then Blacklock shouted, s.n.a.t.c.hed, wrestled for an instant with a writhing captive--and was left with a torn mackintosh in his hands for his only trophy.