At the same time, while blaming Grouchy for his want of foresight and boldness, it must not be forgotten that the state of the roads and of the whole countryside was a very heavy factor against him. It was almost impossible to get the guns through the mud and mire which composed the roads. The infantry had to wade ankle-deep in many places, and for wheeled transport the roads were nearly impassable. Rain had fallen incessantly. Still, much could have been done by the cavalry, which was the arm which should have been relied upon most during these operations; and if the infantry had taken to the fields on either side of the road, they would hardly have marched slower than Vandamme’s men. The Prussians, who were under the necessity of taking with them all their guns, waggons, and trains that they wished to save from the enemy on the same roads that their infantry used, were able to cover nearly 2½ miles an hour. It might be presumed that the French could cover 2 miles an hour. Vandamme, continuing his march while Grouchy breakfasted at leisure at Walhain, reached Nil St Vincent with his corps at 10.30 A.M. Here, in accordance with Grouchy’s orders on the previous evening, he halted, and awaited fresh instructions. It was one o’clock before Grouchy arrived in person, and gave them to him. Then he and Excelmans, who had met with a Prussian rear-guard near Neuf Sart and La Baraque, were ordered to continue their march on Wavre. An hour later, Vandamme’s advanced guard was attacked by Ledebur’s detachment of Hussars, which had been left at Mont St Guibert. Ledebur had remained at Mont St Guibert, unaware of the proximity of the French, until his patrols caught sight of the troops at Nil St Vincent. Then he was alive to the dangers of his situation; for he was indeed in peril of being cut off. Excelmans’ Dragoons at La Baraque stood across his rear, and Vandamme’s Corps was threatening to cut off his retreat by Corbaix. He, however, was a man of great military instinct, and saw that his only chance of escape lay in attacking the French advanced squadrons. This he did with his Hussars, and, being reinforced from Pirch’s Corps by two battalions, which in addition to the battalions which were with him before, made up his detachment to the strength of a brigade, he boldly attacked the head of Vandamme’s column. Grouchy ordered Excelmans to turn Ledebur’s position by Dion-le-Mont, but before the French Cavalry had developed their movement, the Prussians had retreated through the wood of La Huzelle and had fallen back on Wavre. Vandamme was sent off in pursuit, with orders to follow the Prussians to Wavre, take up a position there, and await instructions.