But, as they looked, suddenly a tiny point of fire shot up on the far horizon to the east. It was high enough among the lower stars to surely be on a mountain or crater of some sort, yet so tiny and far away as to be almost indistinguishable in the desert haze. “There’s Sid!” shouted Scotty triumphantly, gripping Niltci’s buckskin-clad arm. “Now, how in the dickens did he ever get way over there? And if so, why did not Blaze come in by _this_ gap?” Niltci stared at the flickering point of light for some time without replying. At times it died down to a mere red coal, so small as to be lost to eyesight entirely. Again it would flare up and appear quite strong. “Mexicanos!” declared the Navaho boy at length. “Mexicans!” echoed Scotty amazedly. “Why, that’s Sid’s camp fire, Niltci. Isn’t it?” “No. Fire, he was be on Cerro Colorado. Master Sidney, him no have go _there_!” answered Niltci. In a flash Scotty saw that he was right. For no conceivable reason could Sid have gone that far distance to climb Cerro Colorado again. No; he had gotten into some sort of adventure with some wandering Indians back near the Hornaday Mountains, that was sure. Blaze’s tracks all argued that. The dog had got away, wounded, and had followed their own tracks to camp, step by step. Meanwhile, what of this Mexican camp fire on Cerro Colorado? It could only mean one thing: Vasquez had taken the train to Nogales in Mexico; had assembled a band of guerrillas; and they had ridden west by Sonoyta and Santo Domingo along the Sonoyta River, and now had climbed Cerro Colorado--for the same reason that Scotty and Sid had--to find Red Mesa! And they had been disappointed. What would their next move now be? Scotty quivered with excitement all over as a possible solution of that question now came to him. Suppose the Mexicans were to push straight across this lava field for Papago Tanks! It was only fifteen miles in an air line. Bad going across the lava, but the Hornaday party had done it, and these Mexican riders could get across in just three hours after daylight! Vasquez was not the man to give up a mine like Red Mesa without scouring this country for it, and Papago Tanks would be his natural base for such an expedition, Scotty argued to himself. These guerrillas would be upon them, then, by noon to-morrow! And meanwhile they themselves were now on the wrong side of the border. It was a case of get out, and get out quick! But where to? One thing was certain: Sid was back somewhere near the Pass. Their whole party must “roll their freight,” as Big John would say, back there early next day, and leave no tracks behind them at Papago Tanks. Tracks! They had left a million of them, written plain in the sands, and there would be no rain to wash them out for a whole season yet. The more Scotty thought it over the more certain he was that F-I-G-H-T! was sure to be the outcome of all this!