This was good strategy, as it was apparently only a matter of time before the mine defenders would have to surrender, and it was little use to sacrifice lives in a mad rush against their rifles.

The attack had splintered the stockade in a score of places, but, thanks to the toughness of the seasoned wood, the bullets that had penetrated had lost most of their strength. Beyond a few scratches from flying splinters, none of the defenders were injured.

"What can they be up to?" wondered Pete, as half an hour passed and no further sign came from the besiegers.

Ramon's figure had now vanished. Perhaps he realized that the fangs of their enemies were by no means drawn, and deemed it more prudent not to take chances on the strength of his "charmed life."

And so the time passed. The sun was well on his march toward the western horizon before there came a move on the part of the enemy, and when it did come it was a startling one. Taking advantage of every bit of cover, the astute mestizos had crept around the stockade till they were in a position exactly behind the defenders. So that, in fact, for the last half hour, the alert rifles of Coyote Pete and his companions had been covering emptiness.

A yell as the attackers charged from the direction into which they had covertly worked themselves apprised the besieged of what had happened. Bitterly blaming his stupidity in not foreseeing such a move, Pete, followed by the others, darted across the stockade. As they were halfway across, however, a dozen or more heads appeared upon the undefended top.

The insurrectos had determined on a bold rush, and unmolested they had succeeded in scaling the walls on each other's shoulders.

"Good Lord!" groaned Pete, as he saw.

Despair was in the countenances of the others, but, even as they halted in dismay at what seemed certain annihilation, a strange thing happened.

With a screaming, earsplitting roar, a white cloud swept from the direction of the boiler house at the clustering forms on the top of the stockade.