The second element in this plan was, contrary to Germany's usual tactics, the determination to attack the center of the French line and break through. Almost three-quarters of a million men were concentrated on this point. The armies of General von Bülow, General Hausen and the Duke of Württemberg were massed in the center of the line. There, however, General Foch's new Ninth Army was prepared to meet the attack. It will be remembered that, in the disposition of the troops, these respective armies were facing each other across the great desolate plain, the ancient battle ground. If the German center could break through the French center, and if at the same time General von Kluck, commanding the German right, could execute a swift movement to the southeast, the Fifth French Army would be between two fires, together with such part of the Ninth Army as lay to the westward of the point to be pierced. This strategic plan held high promise, and it would have menaced the whole interior of France southward from the plain of Champagne, but even this second part of the plan, important as it was, does not appear to have been the crucial point in the campaign.
The glory of the victory, if indeed victory it should prove, as the successes of the previous two weeks had led the Germans to believe, was to be given to the crown prince. With a great deal of trouble and with far more delay than had been anticipated, the crown prince's army had at last managed to get within striking distance of the forefront of the great battle line. His forces occupied the territory north of Verdun to a southern point not far from Bar-le-Duc. Here the German secret service seems to have been as efficient, as it failed to be with regard to conditions only fifty miles away. General Sarrail's army, which confronted the army of the crown prince, was somewhat weak. It consisted of about two army corps with reserve divisions. Nor could General Joffre send any reenforcements. Every available source of reenforcements had been drawn upon to aid the Sixth Army, encamped upon the banks of the Ourcq, in order that Paris might be well guarded. No troops could be spared from the Fifth and Ninth Armies, which had to bear the brunt of the attack from the German center. General Sarrail, therefore, had to depend on the natural difficulties of the country and to avoid giving battle too readily against the superior forces by which he was confronted. It was a part of the plan of the French generalissimo, however, to feel the strength of the German center, and if it proved that they could be held, to release several divisions and send them to the aid of General Sarrail.