THE WAR DIARY—THE REPORT—ROUTINE ORDERS We have heretofore considered those communications which aid combat. We now take up those which have no direct bearing upon the outcome of an engagement. We have seen how the _field message_ makes possible by its fresh information the plan for battle, how the _field_ and _operation orders_ frame that plan for battle, how the _order_ maneuvers the trains in connection with battle, and how _letters_ of _instruction_ issue general directions for a campaign of many battles. We now come to the place where the maneuver, enterprise, or undertaking is over. For a variety of future benefits we must have a record of those occurrences. The _War Diary_ and _The Report_ are the communications which perform that office. THE WAR DIARY Just as certain individuals keep journals of their lives, so the higher military units keep diaries of their existences. “The War Diary is a record of events kept in campaign by each battalion and higher organization and by each ammunition, supply, engineer, and sanitary train. Entries are made daily and should form a concise history of the military operations. A day comprises 24 hours covered Each day’s record will commence with a march table, or statement of the operations or location of the organization, including an account of weather, roads, camp, health of troops, etc., and a statement of the supply of ammunition, rations, and forage. This will be followed by a chronological record of events, including time and place of issue and receipt of orders and messages, with a copy or a synopsis of contents. It is of especial importance that the exact hour and place at which movements are begun and ended, and orders or important messages sent or received be noted. After an engagement, the war diary will contain a report of losses and captures and will be accompanied by a sketch showing the positions of the command at the most important phases. Each day’s record will be attested by the commander or by the adjutant; and, with attached copies of orders and messages sent and received, will be forwarded daily to the next higher commander, who as soon as practicable, after the receipt thereof, will forward the war diary direct to the War Department. Commanders of armies, or of units not components of a higher command, will forward their war diaries direct to the War Department.”[18] Thus these documents become the authentic material for our military history. To go into the War Diary more specifically, let us tabulate what we might actually state therein. We should start with the heading: War Diary, 3d Battalion, 72d Infantry, 3 May, 1920. The date in this case would cover the whole period from midnight May 2/3 to midnight May 3/4.