In consequence of these instructions, NEY became anxious for the speedy concentration of his troops, and again sent Orders to REILLE and D'ERLON to move up their Divisions. The information which he had obtained concerning the Enemy in his front, and GIRARD's report of the assembling of troops in front of Fleurus, induced him to be cautious in his proceedings, and not to attempt any impetuous onset until he could have all his force more in hand, instead of the greater portion of it being, as it then was, lengthened out in Columns of Route along the Charleroi high road; and, in this respect, his views were in perfect accordance with the last despatch which he had received from the Emperor, enjoining him in the first instance, to unite the two Corps of REILLE and D'ERLON. Hence, in debouching from his position at Frasne, about one o'clock, his advance was by no means vigorous: it was limited to a gradual pressing forward of the Light Troops, and amounted to little more than a reconnaissance. About two o'clock, NEY, calculating that D'ERLON's Corps could not be far in his rear, and hoping that the sound of his cannonade would hasten its march, resolved to attack the Enemy's forces which intercepted his advance upon Quatre Bras. PIRÉ's Light Cavalry, constituting a strong line of Skirmishers with well disposed Supports, covered the advance of the Infantry Divisions of BACHELU and FOY, whilst that of JEROME followed as a Reserve. The force with which NEY thus entered the field, consisted of Three Divisions of REILLE's Corps, of PIRÉ's Light Cavalry, of 4 Batteries of Foot, and 1 of Horse, Artillery: altogether-- 16,189 Infantry 1,729 Cavalry 38 Guns. The Prince of ORANGE's force consisted of DE PERPONCHER's Division (with the exception of the 7th Dutch Line Battalion); of 1 Battery of Foot, and 1 of Horse, Artillery: altogether-- 6,832 Infantry 16 Guns. It was not long after two o'clock when the Duke of WELLINGTON returned to Quatre Bras from the Prussian Army. He observed attentively, with his glass, the movements of the French, and told the Prince of ORANGE he would be attacked directly. In a few minutes, the French advanced, and the Dutch-Belgian troops gradually retired; but the Prince, aware of the great advantages which the position of Quatre Bras would derive from the possession of the Farm of Gemioncourt, adjoining the Charleroi road, as also of the Wood of Bossu on the Right, and of the inclosures of Piermont on the Left Flank, endeavoured, with that view, to make a stand, as soon as his Centre reached the first named point. The 5th Battalion of Dutch Militia which occupied this Post, successfully withstood several attacks, during which NEY drew up his forces along the ridge which, intersecting the high road in the immediate (French) rear of Gemioncourt, extends on one side towards the Wood of Bossu, and on the other in the direction of Piermont.