The three points by which the First Brigade was to fall back, were Mont St Aldegonde, for the troops on the right, Anderlues for those in the centre, and Fontaine l'Evêque for the left. In order that they might reach these three points about the same time, ZIETEN ordered that those in front of Fontaine l'Evêque should yield their ground as slowly as the Enemy's attack would admit. Having reached the line of these three points, about ten o'clock, the Brigade commenced its further retreat towards Courcelles, having its proper Left protected by a separate Column consisting of the 1st Regiment of Westphalian Landwehr and two Companies of Silesian Rifles, led by Colonel HOFFMANN, in the direction of Roux and Jumet, towards Gosselies. At Marchienne au Pont stood the 2nd Battalion of the 6th Prussian Regiment, belonging to the Second Brigade of ZIETEN's Corps. The Bridge was barricaded, and with the aid of two guns, resolutely maintained against several attacks; after which these troops commenced their retreat upon Gilly, by Dampremy. In the latter place were three Companies of the 1st Battalion of the 2nd Regiment of Westphalian Landwehr, with four guns. These also retired about the same time towards Gilly, the guns protecting the retreat by their fire from the Churchyard; after which they moved off as rapidly as possible towards Gilly, while the Battalion marched upon Fleurus; but the 4th Company, which defended the Bridge of La Roux until Charleroi was taken, was too late to rejoin the latter, and therefore attached itself to the First Brigade, which was retreating by its Right Flank. * * * * * Lieutenant General Count PAJOL's Corps of Light Cavalry formed the Advanced Guard of the Centre Column of the French Army: it was to have been supported by VANDAMME's Corps of Infantry, but by some mistake, this General had not received his Orders, and at six o'clock in the morning had not quitted his bivouac. NAPOLEON, perceiving the error, led forward the Imperial Guards in immediate support of PAJOL. As the latter advanced, the Prussian Outposts, though hard pressed, retired, skirmishing in good order. At Couillet, on the Sambre, about a mile and a half below Charleroi, the French Cavalry fell upon a Company of the 3rd Battalion of the 28th Prussian Regiment, surrounded it, and forced it to surrender.