To push out along into this immensity is to evince the heart of a brave man or the brain of a fool. The endeavour to traverse the forbidden garden of silence implies on the part of the agent an adventurous nature. Hence it would seem no great task to catalogue those human beings who set their backs to the gentler world and press forward into the naked embrace of this merciless land. Yet as many sorts and conditions come here each year as are to be found outside. Silence, ruthlessness, mystery--these are the attributes of the desert. True, it has its softer phases--veiled dawns and dusks, rainbow hues, moon and stars. But these are but tender blossoms from a spiked, poisonous stalk, like the flowers of the cactus. They are brief and evanescent; the iron parent is everlasting. Chapter I A Bluebird's Feather In the dusk a pack-horse crested a low-lying sand-ridge, put up its head and sniffed, pushed forward eagerly, its nostrils twitching as it turned a little more toward the north, going straight toward the water-hole. The pack was slipping as far to one side as it had listed to the other half an hour ago; in the restraining rope there were a dozen intricate knots where one would have amply sufficed. The horse broke into a trot, blazing its own trail through the mesquite; a parcel slipped; the slack rope grew slacker because of the subsequent readjustment; half a dozen bundles dropped after the first. A voice, thin and irritable, shouted 'Whoa!' and the man in turn was briefly outlined against the pale sky as he scrambled up the ridge. He was a little man and plainly weary; he walked as though his boots hurt him; he carried a wide, new hat in one hand; the skin was peeling from his blistered face. From his other hand trailed a big handkerchief. He was perhaps fifty or sixty. He called 'Whoa!' again, and made what haste he could after his horse. A moment later a second horse appeared against the sky, following the man, topping the ridge, passing on. In silhouette it appeared no normal animal but some weird monstrosity, a misshapen body covered everywhere with odd wart-like excrescences. Close by, these unique growths resolved themselves into at least a score of canteens and water-bottles of many shapes and sizes, strung together with bits of rope. Undoubtedly the hand which had tied the other knots had constructed these. This horse in turn sniffed and went forward with a quickened pace.