Being thus in doubt as to the direction of the retreat of the enemy, he determined to move at first on Sart-à-Walhain, from which point he could march either on Wavre or on Perwez according to the information he might there receive. Inclining probably at this time to the opinion that the Prussians had retreated by way of Perwez, in which case there would be no necessity for unusual haste, he determined to give his troops a good night’s rest. Of the absolute necessity of gaining time in case he should find that the Prussians had retreated on Wavre with the intention of joining Wellington, he seems to have been utterly unmindful. Hence, at or soon after 10 P.M., he issued his orders to his corps-commanders to march in the morning to Sart-à-Walhain. Vandamme,[571] whose corps had bivouacked somewhat in advance of Gembloux, was to start at 6 A.M. It was to be preceded in the march by Exelmans’ cavalry, the bulk of which was at Sauvenières. Gérard,[572] whose troops were in and about Gembloux, was to follow with his corps at 8 A.M. Pajol[573] was ordered from Mazy on the Namur road, where he then was, taking with him the division of Teste, to Grand Leez, where he would receive further orders. Then, at 2 A.M., Grouchy writes to the Emperor to inform him that he was intending to march on Sart-à-Walhain,[574] but without indicating his ulterior course. During the early morning hours, however, information was received[575] which removed his doubts as to the direction of the Prussian retreat, for we find him writing to Pajol[576] “at daybreak,” as follows:— “The movement of retreat of Blücher’s army appears to me very clearly to be upon Brussels.”[577]