The Infantry of Bülow's and Zieten's Corps halted at Genappe: but as soon as the Prussian Advance, including the Cavalry under Prince William, had succeeded in forcing its way through the immense mass of waggons and carriages of all kinds with which this Defile had been blocked up, Gneisenau, moving the Infantry along the road, and flanking it on each side by the Cavalry, continued the pursuit. He succeeded in driving the French from not less than seven bivouacs, which they had taken up in succession; but each of which they abandoned the moment they heard the sounds of the Prussian drums or bugles.
It was an hour after midnight when Napoleon reached Quatre Bras; whence he despatched several Officers to make known to Grouchy the loss of the Battle, and to order him to retire upon Namur. The Officers whom he had previously detached from Genappe to Ligny, for the purpose of moving Girard's Division, which had been left there, into position at Quatre Bras, now brought him word that they had not succeeded in finding it. There appeared to be no possibility of presenting, at this point, any effectual check to the Prussian pursuit. General Nègre of the Artillery was here with the Parks of Reserve, but accompanied by a very feeble escort.
The Soldiers of the First and Second Corps, who, during the advance of the 15th, had crossed the Sambre by the Bridge of Marchiennes, had quitted the high road, both at Quatre Bras and at Gosselies, to proceed in the direction of that point; and with so much precipitation that they could not be halted for the purpose of forming something like a Rear Guard.
The Sixth Corps, the Imperial Guard, and part of the Cavalry, retreated upon Charleroi, whither Napoleon himself proceeded; after having sent his brother Jerome to Marchiennes, with Orders to rally the troops between Avesnes and Maubeuge.
In the mean time, Gneisenau continued his wild nocturnal chase, which was truly Lützow's wilde verwegene Jagd. His followers, however, having been on the march or in action, since daybreak, were becoming weary, especially the Infantry: besides which, several, impelled by hunger, stopped on the way to plunder provision waggons; so that their numbers had greatly diminished.
But Gneisenau, who was the life and soul of the pursuit, and who seemed bent on pushing forward whilst a man and horse remained, now had recourse to a stratagem, which, as regarded its effect upon the Enemy, fully compensated for the exhaustion of his Infantry. Observing that the fugitives always took alarm at the sound of the drum, which announced the presence even of Infantry thus far in pursuit, and close upon their rear; he ordered the last remaining Drummer, who was unable to proceed further on foot, to mount one of the horses that had been disengaged from Napoleon's travelling carriage, and then to keep up with the Cavalry, and beat the drum without intermission.
In this manner Gneisenau passed through Quatre Bras, which had been abandoned on his approach; and even the Heights of Frasne were left free to him; whilst the affrighted Foe, completely scattered and dispersed, endeavoured to escape by Gosselies, Marchiennes, and Charleroi. Upon reaching the Inn of à l'Empereur on the high road beyond Frasne, this favoured companion of Blücher halted his followers, who then consisted but of a few Squadrons and a party of the 15th Regiment, and allowed them to take rest; satisfied with having thus, by mere beat of drum and shouts of triumph, succeeded in scaring the remnant of the French Army across the Sambre.