While it was not disorganized or demoralized, Blücher’s army was in great peril. Two of his army corps were concentrated at Wavre, one was at Gembloux, and the fourth at Wandesett. Had the French been vigilant, these separated corps might have been overwhelmed in detail. Through the carelessness of videttes, the lack of enterprise in the leaders of reconnoitering parties and the unpardonable neglect of General Exelmans, neither Napoleon nor Grouchy was informed of the movement of the Prussian corps. After Grouchy was given command of 33,000 troops to pursue the Prussians, the delays in starting, the slowness of the march, the lack of harmony between Grouchy and his two lieutenants, Vandamme and Gérard, made the “pursuit” the most futile on record. How it was that an army of 70,000 Prussians could get lost to the French, then found, then lost again, is something that the untutored civilian labors in vain to understand. Yet that is the truth about it. The morning after the battle of Ligny the French did not know what had become of the Prussian army. They began to hunt for it. The search was clumsy and far afield. But at length Thielman’s corps was located at Gembloux. Grouchy’s entire army might have enveloped and crushed it. Not being attacked, Thielman sensibly retired, and when the French entered Gembloux they did not even know what had become of those Prussians. A strange “pursuit,” truly. Although he still had two hours of daylight, Grouchy decided that the “pursuit” had been pushed far enough for one day, and he postponed further activities until the morrow. During the night he received intelligence that the whole Prussian army was marching on Wavre. That Wavre was on a parallel line to the line of Wellington’s retreat, and that Blücher’s purpose might be to succor Wellington when necessary never once entered Grouchy’s head. On the contrary, he believed that Blücher was making for Brussels and would not tarry at Wavre. Yet he knew that the Emperor was expecting a battle _just where that of the next day was fought_. Then why not put his 33,000 men nearer to the Emperor than Blücher would be to Wellington? To do so he had but to cross the little river Dyle and march along its left bank. Wavre is on the left bank of the Dyle, and therefore he would have to cross it in any event, going to Wavre. And by maneuvering on that side of the river he could the more readily keep in communication with the Emperor and succor him in case of need. That Napoleon expected Grouchy to do this is shown by the orders which he gave to General Marbot to throw out cavalry detachments in that direction. On the morning of the fateful 18th the well-rested troops of Grouchy might have marched at three. Yet they were not ordered to move till six, and did not actually get under way until about eight. When the French of Grouchy left Gembloux for Wavre, _the Prussians had already been four hours on the desperate march to Waterloo_.