The 1st Hussars of the German Legion, while advancing along the right of the high road, came upon the rear of Vandeleur's Brigade, and were all but in collision with the 11th and 16th British Light Dragoons; which Regiments, having previously ascertained that a Brigade of French Cavalry (Piré's) was on their right, and perceiving, though but dimly, in the dark, the approach of a strong body of horsemen towards their rear, concluded that an attempt was made to intercept their retreat. They immediately went "threes about," and struck into a charge. On the other hand, the 1st German Hussars, not being aware that any British Cavalry was in their front, and misled in a great measure by the sudden clamour of French voices proceeding from the numerous fugitives, who, taking the alarm, were endeavouring to get out of their way, prepared to charge, and gave a loud cheer. This cheer was fortunately recognised by the British Dragoons, when in the act of charging, as that of the 1st German Hussars; and was thus the means of preventing a rencontre that might have been productive of the most fatal consequences to the parties concerned.
Wellington had, previously to this, given Orders that the main body of his Army should halt upon what had been the French position, in the Line of La Belle Alliance; having arranged, by communication with Blücher, that the latter, whose troops were comparatively fresh, should take up the pursuit: and, as the Prussians continued moving forward in great force towards the high road, he directed his own troops to proceed to the right of the latter, so as to leave it clear for their advance. The Prussian Regiments, on passing the British, caused their bands to play the national anthem, GOD save the King! a compliment which was greeted, on the part of the latter, by hearty and friendly cheers.
The Duke now stood with his Advance of both Infantry and Cavalry, on the elevated ground beyond Rossomme, overlooking Maison du Roi. The moon had risen, and by the light it gradually spread over the Field, as also by the objects set fire to at intervals along the high road, the retreating line of his vanquished Foe became sufficiently perceptible to satisfy him that the brilliant victory he had gained was rendered secure beyond a doubt. Having ordered his Advanced Brigades to take up their bivouacs for the night, he returned from this distant part of the Field, and proceeded leisurely along the Charleroi road back towards Waterloo.
Adam's Brigade bivouacked on the spot it had reached; Vandeleur's on the right, near the Wood of Callois in which stood the Observatory; while Vivian, inclining somewhat to his right, led his Hussars much further in advance of the Army, on the French side of the Observatory, and established his bivouac close to the Hamlet of Hilaincourt.
On approaching La Belle Alliance, Wellington ordered the whole of his Army to bivouac on the Field of Battle. On reaching that point, he met Blücher; and mutual congratulations took place between them on the splendid victory achieved. The latter, taking advantage of the designation of the House as felicitously applicable to the meeting of the two Commanders, and considering also that it had constituted the direction point for the advance of the main portion of his troops, styled this glorious contest the Battle of La Belle Alliance. With the promise of vigorously following up the pursuit, and allowing the Enemy no opportunity of rallying within a march from the Field, he took his leave of the Duke; who then continued to ride leisurely towards Waterloo, where he passed the night.
The circumstances of the Duke having established his Head Quarters in this Village, and the name of the latter being more consonant to English pronunciation than that of any other place nearer to the Field, acquired for this ever memorable struggle, the designation, by the British, of the Battle of Waterloo.
Blücher, determined to allow no breathing time to the flying Enemy, and to deprive him of all power of rallying, at least on this side of the French frontier, gave Orders that Bülow's Corps should undertake the pursuit along the Charleroi road; that Zieten's Corps should follow in support of Bülow; and that Pirch's Corps should march by Aywiers, and cross the Dyle, for the purpose of intercepting Grouchy's troops; which, it was presumed, would soon be retreating from Wavre towards the Sambre.
The Prussian Battalions, already mentioned as having turned the Village of Planchenoit, and entered the high road near Maison du Roi, accompanied by only three Squadrons of Uhlans, formed the Advance of the pursuing Army. Gneisenau, placing himself at their head, proceeded to carry into effect the commands of his veteran Chief and friend. The Cavalry, under Prince William, followed; and then the Infantry of the two Corps.
At Genappe, the first important Defile through which the main French Army retired, an immense number of carriages and waggons of all kinds had been collected together—some having been withdrawn from the Field, and others, such as those of the Commissariat or Ordnance Departments, having come up to join, or to follow in the track of, the French Army. By judicious management, these materials, combined with a suitable defence, would have afforded the means of seriously impeding the further pursuit by the victors. Some intention of this kind appeared to have been entertained, as several waggons had been upset, so as to obstruct the crossing of the Bridge, a narrow passage only being left to admit stragglers. But no sooner did the Prussian Advance appear, in the moonlight, descending from the Heights overlooking Genappe, with drums beating and bugles sounding, than the rearmost of the French troops (for Rear Guard there was none to an Army from which all semblance of order and regularity had vanished), immediately after firing a few shots, fled from the place. This was at about eleven o'clock. The quantity of baggage that was collected here presented a rich booty to the Prussians; but the most valuable and most interesting object consisted of Napoleon's travelling carriage, which, with all its contents, fell into the hands of the Fusilier Battalion of the 15th Regiment.