subject the bridges and railroad network to a methodical and intensive bombardment. He stressed the importance of possession of the ridge of Villers-Hélon stating “it is on the heights of Villers-Hélon, and not in the low ground at Longpont Brook, that the defense of the forest of Villers-Cotterêts should be conducted. That same day Mangin submitted a plan of action for an exploratory attack to take some high ground west of Soissons. On 23 June, at a conference in Chaumont, Pershing reminded Foch of the discussion they had at Sarcus where he suggested a counterattack. Foch replied, “studies are being made,” but made no mention of when, where, or whether such an attack would be made. Mangin's exploratory attack was executed on 28 June. According to Mangin, it “tended to prove” the Germans would have difficulty defending their positions against a surprise attack without artillery preparation. Additionally it would offer the best chance of success for an attack on the plateaus southwest of Soissons. On 12 July, Pétain issued instruction No. 14546 to the generals of the Group of Armies of the Reserve and the Group of Armies of the Center to make immediate preparations for an attack. He stated, "The minimum advantage gained should be to deprive the enemy of the use of the Soissons communication net." That same day Pétain issued instructions for an offensive whose purpose was to reduce the Marne salient. This would entail utilizing the French Tenth and Sixth Armies against the western flank of the salient, and the Fifth Army on the eastern flank. The French Tenth Army would carry out the main attack against the Soissons communication network. In support of the main attack, the French Sixth Army would attack south of the Ourcq River while the French Fifth Army would attack the eastern flank of the salient along both banks of the Ardre River with its right flank on the heights south of the Vesle River. At the very least the action of the French Fifth and Sixth Armies would result in preventing enemy reserves from moving against the main attack. The following day Pétain stated the attack should be launched the morning of 18 July while stressing the necessity of secrecy. On 14 July both the American 1st Division and the American 2nd Division were transferred to the French Tenth Army XX Corps under General Pierre Emile Berdoulat. On 15 July,