(CIVIL WAR--TEXAS.) Benjamin S. Roberts. A Union general complains to his Confederate counterpart about his abuse of flags of truce. Autograph Letter Signed as "B.D. Roberts, Brig'r Gen'l Vols., Commanding," to Confederate Major General John B. Magruder. One page, 9¾ x 7¾ inches, with later pencil docketing on verso; lacking integral blank, early repair to 5-inch closed tear. Pass Caballo, Matagorda Island, TX, 16 May 1864 The possession of the coastal Fort Esperanza at Matagorda, TX changed hands several times over the course of the war. This letter was written by the Union commander of the fort to the Confederate commander of the Department of Texas, John B. Magruder. Both men were graduates of West Point (Magruder in 1830, Roberts in 1835), so Roberts called upon their shared professional military culture: "The frequent abuse of the privileges of flags of truce by you and subordinates under your command calls for correction. . . . Due to the humanities of war and the inviolable purity of flags of truce, as a means of aiding such humanities . . . I shall no longer respect any boat or party approaching my military lines, not fully and plainly justified by prescription, custom and the law regulating this subject. All flags of truce expecting to be respected by me hereafter must bear letters authenticating them from authorized commanders, their business must be clearly stated, must be strictly of military nature, and justified by the emergencies of war."