Washington, March 3, 1860.
I am, sir, very respectfully, your obedient servant,
Assistant Adjutant General.
Commanding Department of Texas, San Antonio, Texas.
A dispatch in Difficulties on Southwestern Border, House Documents, Volume 126; Volume 128, United States House of Representatives, U.S. Government Printing Office, 1860
During the 12 years following the Mexican-American War there were present on the frontiers of Texas and Mexico many factors that tended to create disturbances. The topography of the country, the sparsity and general character of its population, the lack of an extradition treaty and of sufficient national authority, wild Indians of uncertain abode, the Mexican tariff system, all caused friction and gave encouragement to lawlessness which not only retarded the development of the region but often threatened to interrupt friendly relations between the two republics. [Border Troubles along the Rio Grande, 1848-1860, The Southwestern Historical Quarterly, Vol. 23, No. 2 (OCTOBER, 1919)]