The Germans were now on the alert to entrap this army that exposed its flank in a long line of march near to the Belgian frontier. Their ubiquitous horsemen captured French despatches which showed them the intended moves in MacMahon's desperate game; Moltke hurried up every available division; and the elder of the two Alvenslebens had the honour of surprising de Failly's corps amidst the woods of the Ardennes near Beaumont, as they were in the midst of a meal. The French rallied and offered a brisk defence, but finally fell back in confusion northwards on Mouzon, with the loss of 2000 prisoners and 42 guns (August 30).
This mishap, the lack of provisions, and the fatigue and demoralisation of his troops, caused MacMahon on the 31st to fall back on Sedan, a little town in the valley of the Meuse. It is surrounded by ramparts planned by the great Vauban, but, being commanded by wooded heights, it no longer has the importance that it possessed before the age of long-range guns of precision. The chief strength of the position for defence lay in the deep loop of the river below the town, the dense Garenne Wood to the north-east, and the hollow formed by the Givonne brook on the east, with the important village of Bazeilles. It is therefore not surprising that von Moltke, on seeing the French forces concentrating in this hollow, remarked to von Blumenthal, Chief of the Staff: "Now we have them in a trap; to-morrow we must cross over the Meuse early in the morning."
The Emperor and MacMahon seem even then, on the afternoon of the 31st, to have hoped to give their weary troops a brief rest, supply them with provisions and stores from the fortress, and on the morrow, or the 2nd, make their escape by way of Mézières. Possibly they might have done so on that night, and certainly they could have reached the Belgian frontier, only some six miles distant, and there laid down their arms to the Belgian troops whom the resourceful Bismarck had set on the qui vive. To remain quiet even for a day in Sedan was to court disaster; yet passivity characterised the French headquarters and the whole army on that afternoon and evening. True, MacMahon gave orders for the bridge over the Meuse at Donchéry to be blown up, but the engine-driver who took the engineers charged with this important task, lost his nerve when German shells whizzed about his engine, and drove off before the powder and tools could be deposited. A second party, sent later on, found that bridge in the possession of the enemy. On the east side, above Sedan, the Bavarians seized the railway bridge south of Bazeilles, driving off the French who sought to blow it up[44].
Over the Donchéry bridge and two pontoon bridges constructed below that village the Germans poured their troops before dawn of September 1, and as the morning fog of that day slowly lifted, their columns were seen working round the north of the deep loop of the Meuse, thus cutting off escape on the west and north-west. Meanwhile, on the other side of the town, von der Tann's Bavarians had begun the fight. Pressing in on Bazeilles so as to hinder the retreat of the enemy (as had been so effectively done at Colombey, on the east of Metz), they at first surprised the sleeping French, but quickly drew on themselves a sharp and sustained counter-attack from the marines attached to the 12th French corps.
In order to understand the persistent vigour of the French on this side, we must note the decisions formed by their headquarters on August 31 and early on September 1. At a council of war held on the afternoon of the 31st no decision
was reached, probably because the exhaustion of the 5th and 7th corps and the attack of the Bavarians on the 12th corps at Bazeilles rendered any decided movement very difficult. The general conclusion was that the army must have some repose; and Germans afterwards found on the battlefield a French order--"Rest to-day for the whole army." But already on the 30th an officer had come from Paris determined to restore the morale of the army and break through towards Bazaine. This was General de Wimpffen, who had gained distinction in previous wars, and, coming lately from Algeria to Paris, was there appointed to supersede de Failly in command of the 5th corps. Nor was this all. The Palikao Ministry apparently had some doubts as to MacMahon's energy, and feared that the Emperor himself hampered the operations. De Wimpffen therefore received an unofficial mandate to infuse vigour into the counsels at headquarters, and was entrusted with a secret written order to take over the supreme command if anything were to happen to MacMahon. On taking command of the 5th corps on the 30th, de Wimpffen found it demoralised by the hurried retreat through Mouzon; but neither this fact nor the exhaustion of the whole army abated the determination of this stalwart soldier to break through towards Metz.
Early on September 1 the positions held by the French formed, roughly speaking, a triangle resting on the right bank of the Meuse from, near Bazeilles to Sedan and Glaire. Damming operations and the heavy rains of previous days had spread the river over the low-lying meadows, thus rendering it difficult, if not impossible, for an enemy to cross under fire; but this same fact lessened the space by which the French could endeavour to break through. Accordingly they deployed their forces almost wholly along the inner slopes of the Givonne brook and of the smaller stream that flows from the high land about Illy down to the village of Floing and thence to the Meuse. The heights of Illy, crowned by the Calvaire, formed the apex of the French position, while Floing and Bazeilles formed the other corners of what was in many respects good fighting-ground. Their strength was about 120,000 men, though many of these were disabled or almost helpless from fatigue; that of the Germans was greater on the whole, but three of their corps could not reach the scene of action before 1 P.M. owing to the heaviness of the roads[45]. At first, then, the French had a superiority of force and a far more compact position, as will be seen by the accompanying plan.
We now resume the account of the battle. The fighting in and around Bazeilles speedily led to one very important result. At 6 A.M. a splinter of a shell fired by the assailants from the hills north-east of that village, severely wounded Marshal MacMahon as he watched the conflict from a point in front of the village of Balan. Thereupon he named General Ducrot as his successor, passing over the claims of two generals senior to him. Ducrot, realising the seriousness of the position, prepared to draw off the troops towards the Calvaire of Illy preparatory to a retreat on Mézières by way of St. Menges. The news of this impending retreat, which must be conducted under the hot fire of the Germans now threatening the line of the Givonne, cut de Wimpffen to the quick. He knew that the Crown Prince held a force to the south-west of Sedan, ready to fall on the flank of any force that sought to break away to Mézières; and a temporary success of his own 5th corps against the Saxons in la Moncelle strengthened his prepossession in favour of a combined move eastwards towards Carignan and Metz. Accordingly, about nine o'clock he produced the secret order empowering him to succeed MacMahon should the latter be incapacitated. Ducrot at once yielded to the ministerial ukase; the Emperor sought to intervene in favour of Ducrot, only to be waved aside by the confident de Wimpffen; and thus the long conflict between MacMahon and the Palikao Ministry ended in victory for the latter--and disaster for France[46].