A corps of cavalry had crossed the Oise and advanced as far as Château Thierry. The First Army, (General von Kluck,) comprising four active army corps and a reserve corps, had passed Compiègne.
The Second Army, (General von Bülow,) with three active army corps and two reserve corps, was reaching the Laon region.
The Third Army, (General von Hausen,) with two active army corps and a reserve corps, had crossed the Aisne between the Château Porcien and Attigny.
More to the east the Fourth, Fifth, Sixth, and Seventh Armies, namely, twelve army corps, four reserve corps, and numerous Ersatz formations, were in contact with our troops, the Fourth and Fifth Armies between Vouziers and Verdun and the others in the positions which have been indicated above, from Verdun to the Vosges.
It will, therefore, be seen that our left, if we accepted battle, might be in great peril through the British forces and the new French Army, operating more to the westward, having given way.
A defeat in these conditions would have cut off our armies from Paris and from the British forces and at the same time from the new army which had been constituted to the left of the English. We should thus be running the risk of losing by a single stroke the advantage of the assistance which Russia later on was to furnish.
General Joffre chose resolutely for the solution which disposed of these risks, that is to say, for postponing the offensive and the continuance of the retreat. In this way he remained on ground which he had chosen. He waited only until he could engage in better conditions.
In consequence, on Sept. 1, he fixed as an extreme limit for the movement of retreat, which was still going on, the line of Bray-sur-Seine, Nogent-sur-Seine, Arcis-sur-Aube, Vitry-le-François, and the region to the north of Bar-le-Duc. This line might be reached if the troops were compelled to go back so far. They would attack before reaching it, as soon as there was a possibility of bringing about an offensive disposition, permitting the co-operation of the whole of our forces.
THE EVE OF THE OFFENSIVE.
On Sept. 5 it appeared that this desired situation existed.