On the evening of Sept. 6, therefore, the fronts and positions of the opposing armies were roughly as follows: Allies. _Sixth French Army_.--Right on the Marne at Meux, left toward Betz. _British Forces._--On the line Dagny-Coulommiers-Maison. _Fifth French Army._--At Courtagon, right on Esternay. _Conneau's Cavalry Corps._--Between the right of the British and the left of the French Fifth Army. Germans. _Fourth Reserve and Second Corps._--East of the Ourcq and facing that river. _Ninth Cavalry Division._--West of Crecy. _Second Cavalry Division._--North of Coulommiers. _Fourth Corps._--Rebais. _Third and Seventh Corps._--Southwest of Montmirail. All these troops constituted the First German Army, which was directed against the French Sixth Army on the Ourcq, and the British forces, and the left of the Fifth French Army south of the Marne. The Second German Army (IX., X., X.R., and Guard) was moving against the centre and right of the Fifth French Army and the Ninth French Army. On Sept. 7 both the Fifth and Sixth French Armies were heavily engaged on our flank. The Second and Fourth Reserve German Corps on the Ourcq vigorously opposed the advance of the French toward that river, but did not prevent the Sixth Army from gaining some headway, the Germans themselves suffering serious losses. The French Fifth Army threw the enemy back to the line of the Petit Morin River after inflicting severe losses upon them, especially about Montceaux, which was carried at the point of the bayonet. The enemy retreated before our advance, covered by his Second and Ninth and Guard Cavalry Divisions, which suffered severely. Our cavalry acted with great vigor, especially Gen. De Lisle's brigade, with the Ninth Lancers and Eighteenth Hussars. On Sept. 8 the enemy continued his retreat northward, and our army was successfully engaged during the day with strong rearguards of all arms on the Petit Morin River, thereby materially assisting the progress of the French armies on our right and left, against whom the enemy was making his greatest efforts. On both sides the enemy was thrown back with very heavy loss. The First Army Corps encountered stubborn resistance at La Tretoire, (north of Rabais.) The enemy occupied a strong position with infantry and guns on the northern bank of the Petit Morin River; they were dislodged with considerable loss. Several machine guns and many prisoners were captured, and upward of 200 German dead were left on the ground. [Illustration: Map 6.--Sept. 9. Forcing the passage of the Marne. This day the German retreat degenerated into a rout, and many captures were made.] The forcing of the Petit Morin at this point was much assisted by the cavalry and the First Division, which crossed higher up the stream. Later in the day a counter-attack by the enemy was well repulsed by the First Army Corps, a great many prisoners and some guns again falling into our hands.