Use of an Umpire to Hide Troop Movements in a War Game

Three maps should be provided, either in separate rooms or separated from each other by screens: one for each player, and one in the centre for the Umpire.* Each Commander and his subordinates will be allowed access only to their own map, the Umpire and his assistants moving from one side to the other.

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Whenever any portion of OIK; of the opposing forces comes within the view of the other, the corresponding blocks of the former must be placed on the map of the latter and rice versa. But it must be borne in mind that these blocks are intended to serve rather as indications of the enemy's presence than to show the exact force at the spot, a question always difficult to ascertain in the field. The Umpire should therefore direct that only such pieces be put on the 1 (layer's map as will correspond with the knowledge he is supposed to have acquired of the enemy's strength, position, c. As events develop themselves the actual force will be shown.

It will thus be seen that at the commencement of the game one player will have blue pieces only on his map, and his opponent red only, while on the Umpire's map both blue and red will be shown. As the game progresses, more and more red pieces will appear on the map of the blue player, and vice versa, till at the end of the game the three maps will, as a rule, present almost the same appearance.

Great Britain War Office, Rules for the Conduct of the War-Game on a Map, 1896 (Classic Reprint)

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