The action of the United States in thus merging its troops with the other armies was hailed with gratitude and praise by the press and official spokesmen of all the Entente nations. The first mention of Americans in the battle of Picardy was contained in the War Department's weekly review of the war situation, issued on April 7. American transport sections, it said, had taken an active part in the battle, and the American Aviation Section was co-operating with the British. THE FIGHTING ENGINEERS American engineers also took part in the battle, particularly during the first days of the German offensive. Three companies belonging to two regiments of the American Railway Engineers were reported in the German War Office statement as operating in the areas of Chauny and the Crozat Canal. This statement was confirmed in a report from General Pershing to the Acting Chief of Staff at Washington. The Americans had been working in the rear lines with Canadian engineers, under Canadian command. When the German attack came, they threw down their tools and seized the weapons with which they had been armed for some months, and formed themselves into a fighting unit. The Germans came on, and finally reached the positions where the Americans were waiting. The number of the engineers was comparatively small. They had no intention of retreating, however, and were bent upon killing all the Germans possible. As the first enemy wave advanced, the American forces let them come until they were within certain range: then opened fire, pouring in a storm of bullets. Gaps appeared in the advancing lines at many places, but the German waves came on, without firing a single shot. The Americans were unable to understand these tactics. By this time their weapons were so hot that they could not be used effectively, and the enemy was close, so that the engineers retired, fighting, took up another position, then turned and began operations again. A British officer who witnessed the engagement is reported to have said: "They held on by their teeth until the last moment, inflicting terrific casualties on the enemy. Then they moved back and waited for the Germans, and repeated the performance." By the time the engineers reached a place somewhere near Noyon they were nearly exhausted and almost without equipment. There they had a chance to rest and re-equip. On the sectors where American troops had been stationed before the decision to place them at the disposal of General Foch intensive training operations in the front-line trenches, with artillery fire and raiding of the enemy's positions, had been proceeding along much the same lines as during the previous month. A dispatch dated April 3 reported that American troops on a certain sector other than that in the region of Toul had been subjected to an extraordinarily heavy gas attack.