And finally, that the orders, movements, and results of the sixth day of April, 1862, must be judged by their relations to the passing hours and issues of that day, as practical men would act under changing conditions, and not by any formal order, which, however appropriate at one time, would, at any other time, defeat the work in hand. The Rules of Evidence, recognized by Civil and Military Courts alike, are but expressions of sound judgment of past experience; and Military Science, so called, has no other basis than that which belongs to the wise use of means to ends in all applied science and in all human endeavor. Whenever, therefore, the conduct of a battle is consistent with the conditions, as at the time understood, it is not exactly just to measure it by the terms of any instructions inconsistent with those conditions;--so that while an order to march to Pittsburg Landing became necessary upon the retirement of the original line, it ought not to be technically applied back to a time when that line was supposed to be sweeping on to victory and only sought fresh strength to mature that victory. That a general action was precipitated by the Confederate forces under General Albert Sidney Johnson and was in the nature of a successful surprise of the Union Army, is the fact which harmonizes the reports of officers of both armies with the incidents of the day, and fairly distributes responsibility, without reflecting the narrow escape of the Union Army from destruction upon any single officer or command; especially, where all did so well, and so much is to be credited to the fall of General Johnson and the interruption of his deliberate plan, first to surprise, and then sweep on to victory, at whatever cost. The Documents are as follows: 1st. Letter of Major General Lew Wallace to General U.S. Grant, February 26, 1869. 2nd. Letter of Lieutenant Colonel Ross, A.D.C. to General Wallace, January 25, 1868. 3rd. Letter of General J.A. Strickland to General Wallace, January 24, 1868. 4th. Letter of General G.F. McGinnis to General Wallace, February 20, 1868. 5th. Letter of General Fred. Knefler to General Wallace, February 19, 1868. 6th. Letter of Captain Ad Ware, A.D.C., to General Wallace (without date). 7th. Letter of General John M. Thayer to General Wallace, March 4, 1868. 8th. Letter of General U.S. Grant to General Wallace, March 10, 1868, commenting upon the letters cited and suggesting their publication, in justice to General Wallace.