The difficulties of marching across the country by way of Mont St. Guibert to the Dyle were also dwelt upon,—the chief-of-artillery of the 4th Corps, Baltus, having great doubts as to the possibility of such a march, and the chief-of-engineers, Valazé, offering to remove the obstacles. Grouchy finally decided to resume the march towards Wavre. His army marched in a single column by the road which, passing through Nil St. Vincent and just to the north of Corbaix, reaches La Baraque, and thence leads to Wavre by a line, almost straight. Not a half a mile beyond La Baraque there is a road which leads to the bridge of Moustier, less than three miles off; three-quarters of a mile farther on is another road, which, with its branches, leads to the bridges of Limelette and Limale, at a distance of only two miles. Half a mile north of the bridge of Moustier is another bridge, that of Ottignies. These bridges had not been destroyed, and they were all unguarded.[595] Then there were convenient woods able to conceal any movement of the troops towards the river. There was a slight affair in a wood a short distance beyond La Baraque, in which the cavalry of Ledebur,[596] assisted by two battalions of infantry, skirmished for an hour or so. While this was going on, two divisions of the IId Corps, which had been making their way through the town of Wavre, were brought back, and took up position, facing south, about a mile south of the town. But there was no resistance to speak of. When the French advanced, the Prussians retired on Wavre. In its march, which was made to the sound of the cannon of Waterloo,[597] the army of Marshal Grouchy had then abundant opportunity to cross the Dyle at Moustier and Ottignies, at Limelette and Limale.[598] La Baraque, on the main road to Wavre, from near which the roads to these bridges diverge, was reached about two o’clock.[599] From this point on to Wavre, the Prussians were clearly to be seen marching to the field of Waterloo.[600] If Grouchy had in season recalled Pajol and the division of Teste from the extreme right of the column, in order to mask the movement by threatening Wavre, it would certainly seem that Vandamme’s Corps might have crossed at Limale and Limelette, and Gérard’s at Ottignies and Moustier, and that, before 4 P.M., the whole force could have been _en route_ for St. Lambert.[601] The fact is, the whole question of Grouchy’s flank march at noon has been unnecessarily confused by three very general misconceptions, namely:— (1) That it was at Sart-à-Walhain where the sound of the cannon was heard. It was at Walhain, a good mile nearer to the bridges.