So far in the siege Del Rey had kept under cover, patrolling the streets and plaza and letting the volunteers fight, but now the war had shifted to his territory and his _rurales_ were running like mad. For, matching treachery against deceit, the rebel leaders had sent men around to slip up near the town and at the first fusillade from the hillside they came charging up the creek. Then it was that the ever-watchful _rurales_ proved their worth. As the rebels appeared in the open they ran to the outlying houses and, fighting from the flat roofs, checked the advance until the miners could come to their aid. But in the confusion another party of rebels had rushed down the gulch from the west, and while the fight was going on in the lower town they found lodgment in a big adobe house. And now for the first time there was fighting in earnest--the house-to-house fighting that is seen at its worst in Mexico. While women screamed in the _casa grande_ and the Americans paced to and fro on the hill, the boom of a dynamite bomb marked the beginning of hand-to-hand. With a fearlessness born of long familiarity with explosives the Sonoran miners advanced valiantly with their hand-grenades--baking-powder cans filled with dynamite and studded with fulminating caps. Digging fiercely through wall after wall they approached unperceived by the enemy and the first bomb flung from a roof filled the adobe with wounded and dead. A dense pall of yellowish smoke rose high above the town and, as bomb after bomb was exploded and the yells of the miners grew louder with each success, the stunned invaders broke from cover and rushed helter-skelter up the gulch. Then there was a prodigious shouting from the Sonorans and more than one triumphant grenadier swung his can of giant powder by the sling and let it smash against the hill in a terrific detonation. In the big house all was confusion. Soon the cheers of the defenders heralded victory and, in spite of all efforts to restrain them, the wives of the miners rushed into the open to gaze upon the triumph of their menfolk. On the hilltops the ineffective rebel riflemen rose up from behind their stone wall to stare, until suddenly they, too, were seized with a panic and ran to and fro like ants. Then, around the curve below the concentrator, a tall man came dashing up on a pure white horse, and behind him, charging as he charged, came the swarthy Yaquis of Alvarez, their new rifles gleaming in the sun. Up along the hillside and after the fugitives they ran with vengeful eagerness, racing one another for the higher ground and the first shot at the rebels. First Alvarez on his white horse would be ahead and then, as they encountered rocks, the Yaquis would surge to the front. It was a race and at the same time it was a rout, for, at the first glimpse of that oncoming body of warriors, the cowardly followers of Bernardo Bravo took to their heels and fled.