THE DEAD MANS JOURNEY—Journada del Muerte, the locals called it the blistering ocean of sand and sage between the Rio Grande River to the west and the Sacramento mountain range to the east. The bones of men and horses had bleached in the mile-high desert for three hundred years. Spanish conquistadors were the first white men to explore this new furnace of the Southeastern New Mexico Territory—and the first to perish. In the thin air, the riders coming down the mountain were sharply etched against the blue sky. Steam, blowing out of the ice-encrusted nostrils of their mounts and their two pack horses, surrounded the horsemen in a white veil. Descending the eastern face of the Sacramento mountains, the horses walked slowly and painfully on cracked hooves.