Ajo, Arizona sank into restless sleep under a sky without stars.  Each night the townspeople dreamed each pretty much the same dream.  They kept walking along scarred railroad tracks out toward the Cabeza Prieta National Wildlife Refuge.  They kept looking for the long trains that used to haul away the copper.  Even though they could feel the railbed shake and watch the trembling light on the locomotive bear down on them, no train ever came.