Military critics say that this was the greatest mistake made by the Emperor Napoleon's advisers; and that, had the forces under Bazaine retreated farther to the west--after throwing a sufficient garrison into Metz-- they might have been able to effect a junction with the defeated army of Mcmahon, which that general was withdrawing into the interior and from which they were now completely cut off.
Be that as it may, however, during this interval of inactivity, when the shattered fragments of the magnificent French army--which had so proudly assumed the offensive but a bare fortnight before along the frontiers of the Rhine--were idling away precious moments that were fraught with peril and disaster to the Gallic race, the huge German masses, animated by a sense of victory and the consciousness of a superiority in arms as well as in numbers, were sweeping forward like a whirlwind of destruction.

The Crown Prince, who had routed Mcmahon at Woerth and driven the wedge in that separated him from Bazaine, continued his onward march on the left of the German line through the passes of the Vosges into the fertile plains of Champagne.

At the same time, Prince Frederick Charles, with the main portion of the second army, had crossed the Moselle at Pont-a-Mousson; and, moving northwards, was already in a position to threaten the line of the French retreat on Verdun, while the remainder of the Red Prince's forces were advancing to the eastward of Metz.

The columns, too, of Steinmetz, moving with mathematical regularity at an equal rate of progression, were also being echelonned along the northern face of the fortress, just within striking distance.
To put it concisely, some two hundred and fifty thousand unbeaten German soldiers, with an artillery numbering over eight hundred guns, almost surrounded the stronghold of Lorraine and the far weaker and partly demoralised force which the French had gathered together beneath its walls, only, as it turned out subsequently, to court defeat and annihilation.
It was not until the 14th of August that the series of battles that were to rage round Metz, began.
Early in the morning of that day--apparently for the first time struck with an apprehension of having his retreat on Chalons by way of Verdun interfered with and his communications with his base of supply cut off, thus appreciating his critical position only when it was too late to remedy it--the French Marshal commenced crossing the Moselle with his vanguard.

The entire body of troops, however, did not reach the river; for, three corps, which had been encamped to the eastward of the fortress, delayed their departure until the afternoon--a tardiness that enabled Steinmetz to attack their rear and detain them on the spot, until the flanking movement of Prince Frederick Charles' army beyond the Moselle towards Pont-a-Mousson had been completed.