It will thus be seen that GROUCHY's report, despatched from Gembloux on the previous night, was well calculated to inspire the Emperor with great confidence as to the result of his present plan of operations, notwithstanding the very little progress that had hitherto been made in that quarter; and which, as already remarked, must be ascribed principally to his own inactivity during the early part of the 17th. He approved of the movement upon Wavre, in pursuit of the great mass of the Prussian Army: but at the same time expressed his desire that it should be executed in such a manner as to draw the Detached Force more within the sphere of the operations of the main French Army; and above all, he enforced the necessity of maintaining a close communication with the latter. Some time before the Battle commenced, a Prussian Patrol reached the Village of Smohain, in which was posted the Picquet of the 10th British Hussars, under Captain TAYLOR; whom the Officer accompanying the Patrol desired to report to the Duke of WELLINGTON that General Count BÜLOW was at St Lambert, and advancing with his _Corps d'Armée_. Captain TAYLOR immediately despatched Lieutenant LINDSEY, of the 10th, with the intelligence to Head Quarters, as directed. The Prussian Officer was certainly ignorant of the very slow progress made by the main body of BÜLOW's Corps; and the information which he thus conveyed to the Duke, before the Battle had commenced, naturally led the latter to calculate upon a much earlier arrival of the Prussians than could possibly take place: for, in point of fact, it was only BÜLOW's Advanced Guard which had then reached St Lambert. * * * * *