In considering the defense of the line of the western frontier of Texas our relations with the civilized Indians north of Red River are of the utmost importance. Numbering some eight thousand rifles, they form a strong barrier on the north, forcing the line of operations of an invading army westward into a region impracticable to the passage of large bodies of troops. Regarding them as our allies, which their natural affinities make them, the line of the western frontier reduces itself to the country between the Rio Grande and Red River.--_Official Records_, first ser., vol. i, 628. [152] Between Fort Washita and Fort Arbuckle, Colonel Emory was overtaken by William W. Averell, second lieutenant, Regiment Mounted Rifles, with additional despatches from Townsend, ordering him, upon their receipt, immediately to repair to Fort Leavenworth, "with all the troops in the Indian country west of Arkansas" [_ibid._, 667]. Lieutenant Averell's own account of his experiences on the journey between Washington City and Fort Washita, the hardships, difficulties, and delays, also the frenzied excitement of the Arkansas people over the prospect of secession, forms an interesting narrative [_ibid._, vol. liii, supplement, 488, 493-496]. [153] Black Beaver had served creditably as United States interpreter for the Wichitas and recently Leeper had turned to him for help in allaying their fears [Leeper to Rector, dated Wichita Agency, March 28, 1861, _Leeper Papers_]. For services rendered on this expedition northward to Fort Leavenworth [Letter of W. S. Robertson, September 30, 1861, General Files, _Southern Superintendency_, _1859-1862_, R1615], Black Beaver brought a claim against the United States [E. S. Parker to J. D. Cox, July 1, 1869, Indian Office, _Report Book_, no. 18, pp. 417-418; and same to same, April 25, 1870, _ibid._, no. 19, p. 321]. Evidently Black Beaver served also in the Mexican War. He was then head of a company of mounted volunteers, Shawnees and Delawares [George W. Manypenny to Drew, August 8, 1854], which had been called and mustered into the service by Harney [P. Clayton, 2nd auditor, to A. K. Parris, 2nd comptroller, October 26, 1850]. [154] Emory to Townsend, May 19, 1861 [_Official Records_, first ser., vol. i, 648]. [155] Captain S. T. Benning to Walker, May 14, 1861 [_Official Records_, first ser., vol. i, 653.] [156] --_Ibid._ [157] Leeper to Rector, January 13, 1862 [_Leeper Papers_]. [158] A note, communicated by X. B. Debray, aide-de-camp to the Governor of Texas, to Walker and dated, Richmond, August 28, 1861, says,