It was nearly four o'clock when VANDAMME's Corps arrived in front of the position which THIELEMANN was in the act of quitting, with a view to follow and support the remaining three Prussian Corps that were at that moment on the march towards the Field of Waterloo; and, with a fire that was opened from the French Batteries, commenced the Battle of Wavre, which will be described in its proper place in a subsequent Chapter. CHAPTER IX. It rained incessantly during the night of the 17th, occasionally in torrents; whilst loud and frequent peals of thunder fell ominously on the ear of the toil-worn soldier, startling him from the fitful slumber, which was all the rest the chill and comfortless bivouac on the Field of Waterloo could afford him in that tempestuous night. Scarcely had the morning dawned when the numerous groups, stretched around the smouldering remains of the bivouac fires, or couched in the hollows, or lying under such slender cover as the few trees and brushwood within range of the positions of their respective Regiments afforded, were seen gradually in motion; and as the eye of an observer wandered along the space which lay between the main bodies of the hostile Armies--a space varying in no greater width than from one thousand to fifteen hundred yards--the Officers in command of the several Picquets might be seen, on either side, withdrawing their Vedettes and Sentries from the very limited and almost conversational distance that had separated them from their opponents during the night, concentrating their Detachments, and establishing their Main Posts more within the immediate range of the respective positions occupied by the grand Armies. As the morning advanced, the dense vapoury masses which had so long rolled slowly and heavily over the plain, gradually began, as if relieved by the constant discharge of their contents, to soar into a higher region, where, during the whole day, with little or but imperceptible motion, they hung spread out into a broad expansive vault, through which the rays of the sun were unable fully to penetrate, until just at the moment of its sinking from the scene of strife, when it shed the full blaze of its setting splendour upon the victorious advance of the Anglo-Allied Army. The drying and cleaning of firearms soon became general, and the continuous discharge of muskets, at rapid and irregular intervals, fell upon the ear like the rattle of a brisk and widely extended skirmish.