GENERAL CHARACTER OF THE ACTION.
As early as Sept. 11 the Commander in Chief had directed our left army to have as important forces as possible on the right bank of the Oise. On Sept. 17 he made that instruction more precise by ordering "a mass to be constituted on the left wing of our disposition, capable of coping with the outflanking movement of the enemy." Everything led us to expect that flanking movement, for the Germans are lacking in invention. Indeed, their effort at that time tended to a renewal of their manoeuvre of August. In the parallel race the opponents were bound in the end to be stopped only by the sea; that is what happened about Oct. 20.
The Germans had an advantage over us, which is obvious from a glance at the map—the concentric form of their front, which shortened the length of their transports. In spite of this initial inferiority we arrived in time. From the middle of September to the last week in October fighting went on continually to the north of the Oise, but all the time we were fighting we were slipping northward. On the German side this movement brought into line more than eighteen new army corps, (twelve active army corps, six reserve corps, four cavalry corps.) On our side it ended in the constitution of three fresh armies on our left and in the transport into the same district of the British Army and the Belgian Army from Antwerp.
For the conception and realization of this fresh and extended disposition the French command, in the first place, had to reduce to a minimum the needs for effectives of our armies to the east of the Oise, and afterwards to utilize to the utmost our means of transport. It succeeded in this, and when, at the end of October, the battle of Flanders opened, when the Germans, having completed the concentration of their forces, attempted with fierce energy to turn or to pierce our left, they flung themselves upon a resistance which inflicted upon them a complete defeat.
DEPLOYMENT OF A FIRST ARMY.
The movement began on our side only with the resources of the army which had held the left of our front during the battle of the Marne, reinforced on Sept. 15 by one army corps.
This reinforcement, not being sufficient to hold the enemy's offensive, (district of Vaudelincourt-Mouchy-Uaugy,) a fresh army was transported more to the left, with the task "of acting against the German right wing in order to disengage its neighbor, ... while preserving a flanking direction in its march in relation to the fresh units that the enemy might be able to put into line."
To cover the detrainments of this fresh army in the district Clermont-Beauvais-Boix a cavalry corps and four territorial divisions were ordered to establish themselves on both banks of the Somme. In the wooded hills, however, which extend between the Oise and Lassigny the enemy displayed increasing activity. Nevertheless, the order still further to broaden the movement toward the left was maintained, while the territorial divisions were to move toward Bethune and Aubigny. The march to the sea went on.
From the 21st to the 26th all our forces were engaged in the district Lassigny-Roye-Peronne, with alternations of reverse and success. It was the first act of the great struggle which was to spread as it went on. On the 26th the whole of the Sixth German Army was deployed against us. We retained all our positions, but we could do no more; consequently there was still the risk that the enemy, by means of a fresh afflux of forces, might succeed in turning us.
Once more reinforcements, two army corps, were directed no longer on Beauvais, but toward Amiens. The front was then again to extend. A fresh army was constituted more to the north.