Two men were sitting beside a camp-fire at Saddle Pass, a shallow notch in the lower end of the Sangre de Cristo Range in southern Colorado. Although it was the middle of June and summer had come to the valleys below, up here in the mountains the evenings were still chill, and the warmth of the crackling fire felt grateful to tired bodies. Daylight yet held, although it was fast deepening toward dusk. The sun had been gone some little time behind the purple grandeur of Sierra Blanca, but eastward the snowy tips of the Spanish Peaks were still flushed with the afterglow.