The French so far had made no serious attempt at Saarbrücken; Lieutenant-Colonel Pestel, with one battalion and three squadrons, was able successfully to withstand their petty attacks. It had meanwhile been observed that the hostile forces were moving farther to the right, towards Forbach and Bitsch. This seemed to indicate that the two French Corps known to be about Belfort and Strasburg, might purpose crossing the Rhine and marching through the Black Forest. It seemed therefore all the more important that the IIIrd Army should be set in motion as early as possible, for one thing to protect the right bank of the Upper Rhine by an advance on the left; for another, to cover the left flank of the IInd Army during its advance.
A telegraphic order to that effect was despatched on the evening of July 30th, but the Head-quarters of the IIIrd Army wished to wait for the arrival of the VIth Corps and of the trains. Whereupon, regardless of this delay, the IInd Army was put in march towards the Saar, where the French were beginning to be active.
The time had gone by when they might have taken advantage of their over-hasty mobilization; the inefficient condition of the troops had paralyzed every attempt at activity. France had been long waiting for the news of a victory, and something had to be done to appease public impatience. So, in order to do something, it was resolved (as is usual in such circumstances) to undertake a reconnoissance in force, and, it may be added, with the usual result.
On August 2nd three entire Army Corps were set in motion against three battalions, four squadrons, and one battery in Saarbrücken. The Emperor himself and the Prince Imperial shared in the enterprise. The IIIrd Corps advanced on Völklingen, the Vth through Saargemünd, the IInd on Saarbrücken.
Saarbrücken was evacuated after a gallant defence and repeated counter-strokes, but the French did not press across the Saar; convinced, possibly, that they had wasted their strength in a stroke in the air, and had nowhere gained any insight into the dispositions of the enemy.
The French military chiefs now hesitated for a long while between conflicting resolutions. Orders were given and recalled on the strength of mere rumours. The left wing was reinforced because 40,000 Prussians were supposed to have marched through Trèves, the Guard received contradictory orders, and the bare apparition of a small German force about Lörrach in the Black Forest occasioned the order that the VIIth Corps must remain in Alsace. Thus the French forces were straggled over the wide area between the Nied and the Upper Rhine, while the Germans were advancing in compact masses towards the Saar.