During all this time the other occupants of the camp had not been idle. Under the Captain's directions, his gang of Spaniards had formed a bucket line from the ditch to the tents, and they soon had the little dwellings dripping with water. The teamster had got his frightened mules out of the corral and led them to a place of safety on the grade, and the two engineers had run the truck out on the road beyond the line of flames. Their tasks done, all--Americans and Spaniards--worked to get their most valuable possessions to a place on the grade were they would be safe. They had but little time to work, however, for the intense heat soon drove them back to the road, where they gathered together and watched anxiously the meeting of the fires. They had not long to wait. With a roar, in which was mingled the cries of the tortured animals, the advancing wall of fire swept down on the thin line of back fire. Our little party held their breath and waited. If the wall of flame leaped the dozen or so feet the back fire had eaten away, their camp was gone. Five minutes and a transformation had taken place. Of the mighty conflagration nothing remained but the blacked, smoking dirt of the prairie. The back fire had vanquished its mighty rival. But the danger was not yet over. The wind had swept bits of blazing grass down among the tents, and tiny fires were springing up in a hundred different places. These the boys and their followers beat out with the green branches of the spruces. It was a full half hour before the last of them was extinguished, and they were able to stop and rest, and take account of the damage done. No one was seriously hurt, but all bore marks of the conflict, in the way of burned clothing, singed hair, and blisters, but all were too happy over the saving of the camp to pay much attention to these minor injuries. "Whew! that was a close shave," said Walter; "but all's well that ends well. By the way, I didn't see anything of McCarty and his crew. I should have thought he would have come in with his men and given us a hand." "Perhaps he has had his hands full out there," suggested Captain Westfield. "Maybe that fire was just set so as to draw the men off the machine." "I never thought of that," said Charley, anxiously. "The fire drove everything else out of my head. Let's go out and see what's the matter. The machine isn't running." As if in answer to their conversation, there came from the machine three long blasts of the whistle, a pause, then four long blasts. "The signal for the wagon, and the distress signal," Walter cried. The three lads went forward on the run, followed by half a dozen curious Spaniards. The Captain remained behind to keep an eye on the camp. The boys were half way to the machine when the signals sounded again--three long blasts, followed by four long blasts.