The map itself shows the location of all divisions, both the enemy and allied, on the western front; the correct battle line, commanding generals, location of headquarters and boundaries down to include armies, and various other information concerning divisions, as, for example, whether they were fresh or tired. The map was developed and kept posted to date daily by the third section of General Pershing's staff, and used by them and other superior officers during active operations for strategical studies and purposes of general information. It is evident that during the war the information which this map contained was such that the enemy would have spared no pains to secure it. Every precaution was taken to insure its secrecy, and to this end the map was always kept locked up, and in addition was kept in a small compartment formed by a closed screen. Furthermore, access to this map was had by only the half dozen chiefs of the general headquarters staff sections whose work was directly affected by the changes shown on the map. This map appears to have been unique. The staff officers from the different allied headquarters who had occasion to see the map declared that it was the most complete representation of the opposing forces that they had seen. General Pershing, in his letter to the adjutant general suggesting the public display of the map in the National Museum, says: "It has occurred to me that this particular map with its accompanying installation will have a great historical value. It will be of intense interest to future generations, not only because it was the only map of its kind used at these headquarters, but because it shows in a vivid fashion the exact situation at the hour of the armistice."] [Sidenote: Difficult tasks of engineers and gunners.] In the chill rain of dark nights our engineers had to build new roads across spongy, shell-torn areas, repair broken roads beyond No Man's Land, and build bridges. Our gunners, with no thought of sleep, put their shoulders to wheels and dragropes to bring their guns through the mire in support of the infantry, now under the increasing fire of the enemy's artillery. Our attack had taken the enemy by surprise, but, quickly recovering himself, he began to fire counterattacks in strong force, supported by heavy bombardments, with large quantities of gas. From September 28 until October 4 we maintained the offensive against patches of woods defended by snipers and continuous lines of machine guns, and pushed forward our guns and transport, seizing strategical points in preparation for further attacks. [Sidenote: The Twenty-seventh and the Thirtieth with the British.]