Perceiving the formidable advance and overwhelming force of the Enemy, he did not hesitate a moment in carrying those Orders into effect, and made his dispositions accordingly; but the retreat had scarcely commenced when his Battalions were vigorously assailed by the French Cavalry. NAPOLEON, in the hope of profiting by this retrograde movement, sent against the retreating Columns the four Squadrons _de Service_ of the Guard, under General LETORT, a distinguished Cavalry Officer attached to his Staff. The Prussian Infantry withstood the repeated attacks of the French Cavalry with undaunted bravery, and aided by the gallant exertions of Lieutenant Colonel WOISKY, who boldly met the Enemy with the 1st West Prussian Dragoons, and checked his progress, the greater part of it succeeded in gaining the Wood of Fleurus. The Fusilier Battalion of the 28th Regiment (of which it will be recollected, one Company had previously been captured on the right bank of the Sambre) was the only Column broken on this occasion. It had been ordered to retire into the Wood by Rondchamp, but before it could complete the movement, it was overtaken by the Enemy's Cavalry, by which it was furiously assailed, and suffered a loss of two thirds of its number. The Fusilier Battalion of the 6th Regiment was more fortunate. When about five hundred paces from the Wood, it was attacked by the Enemy's Cavalry on the plain, but forming Square, and reserving its fire until the French horsemen had approached within twenty or thirty paces, it gallantly repelled several charges. As the vigour with which these attacks were made began to slacken, the Battalion cleared its way with the bayonet through the Cavalry that continued hovering round it. One of its Companies immediately extended itself along the edge of the wood, and kept the French Cavalry at bay. The latter suffered severely on this occasion, and General LETORT who led the attacks was mortally wounded. The Brandenburg Dragoons had been detached by ZIETEN in support of PIRCH's Brigade, and opportunely reaching the Field of Action, made several charges against the French Cavalry, which they repulsed and compelled to relinquish its pursuit. PIRCH's Brigade now took up a position in front of Lambusart, which was occupied by some Battalions of the Third Brigade, and General RÖDER joined it with his remaining three Regiments of Cavalry and a Battery of Horse Artillery. At this moment, the French Cavalry, which was formed up in position, opened a fire from three Batteries of Horse Artillery, and thus brought on a cannonade, with which, however, the affair terminated. The First Prussian Brigade having safely executed its retreat from Heppignies, towards Fleurus, reached St Amand about eleven o'clock at night.