Suddenly Slone began to pound the patient Nagger and to cry out to him in wild exultance. "Old horse, we've got him! ... We've got him! ... We'll put a rope on him before this time to-morrow!" Slone yielded to his strange, wild joy, but it did not last long, soon succeeding to sober, keen thought. He rode down into the bowl a mile, making absolutely certain that Wildfire could not climb out on that side. The far end, beyond the monuments, was a sheer wall of rock. Then he crossed to the left side. Here the sandy slope was almost too steep for even him to go up. And there was grass that would burn. He returned to the pass assured that Wildfire had at last fallen into a trap the like Slone had never dreamed of. The great horse was doomed to run into living flame or the whirling noose of a lasso. Then Slone reflected. Nagger had that very morning had his fill of good water--the first really satisfying drink for days. If he was rested that day, on the morrow he would be fit for the grueling work possibly in store for him. Slone unsaddled the horse and turned him loose, and with a snort he made down the gentle slope for the grass. Then Slone carried his saddle to a shady spot afforded by a slab of rock and a dwarf cedar, and here he composed himself to rest and watch and think and wait. Wildfire was plainly in sight no more than two miles away. Gradually he was grazing along toward the monuments and the far end of the great basin. Slone believed, because the place was so large, that Wildfire thought there was a way out on the other side or over the slopes or through the walls. Never before had the far-sighted stallion made a mistake. Slone suddenly felt the keen, stabbing fear of an outlet somewhere. But it left him quickly. He had studied those slopes and walls. Wildfire could not get out, except by the pass he had entered, unless he could fly. Slone lay in the shade, his head propped on his saddle, and while gazing down into the shimmering hollow he began to plan. He calculated that he must be able to carry fire swiftly across the far end of the basin, so that he would not be absent long from the mouth of the pass. Fire was always a difficult matter, since he must depend only on flint and steel. He decided to wait till dark, build a fire with dead cedar sticks, and carry a bundle of them with burning ends. He felt assured that the wind caused by riding would keep them burning. After he had lighted the grass all he had to do was to hurry back to his station and there await developments. The day passed slowly, and it was hot. The heat-waves rose in dark, wavering lines and veils from the valley. The wind blew almost a gale. Thin, curling sheets of sand blew up over the crests of the slopes, and the sound it made was a soft, silken rustling, very low. The sky was a steely blue above and copper close over the distant walls.