Cheyenne Indians. Colorado Have Black Kettle's letter proposing exchange of prisoners, Ft. Lyon, 1864. Hall. History Letter proposing exchange of prisoners intercepted, Ft. Lyon, 1884. Hall. Hist. Colo. v.1 p.333 Mrs. Snyder, white captive, commits suicide, 1864. Hall. Hist. Colo. v.1 p.335 Hold council; release white prisoners, 1864. Hall. Hist. Colo. v.1 p.335 0