1971 Apollo Books edition. US Marshall Al Palmer had been summoned from the Dakota territory to Washington DC in the early spring of 1869 and sat listening to assistant Secretary of war Jonas Lamphere unwind, a gruesome tale, which was shortly to become his next assignment.  deep in the Rocky Mountains of the little known Colorado territory major Larson a former confederate army officer secretly holds over 2000 union soldiers in slavery for more than four years. Larson has been mining silver with northern soldiers taken captive during the Civil War in an in escapable box canyon slave mine Larson is sending silver to the south for reconstruction. Larson‘s natural fortress is revealed in history to be devils cloth a canyon named by the Indians and virtually impossible to escape from or attack.  in 1869 few white men knew anything of the new and savagely beautiful Colorado territory. Al Palmer was one of the few. He was tough cunning and ruggedly handsome Palmer was a loner and save for the small glint of his badge. he looked every bit the part of a white man turned Indian .