“It is important to penetrate what the enemy is intending to do; whether they are separating themselves from the English, or whether they are intending still to unite, to cover Brussels or[476] Liége, in trying the fate of another battle.[477] In all cases, keep constantly your two corps of infantry united in a league of ground, and occupy every evening a good military position, having several avenues of retreat. Post intermediate detachments of cavalry, so as to communicate with headquarters.
Dictated by the Emperor,
in the absence of the major-general, to the
Grand-marshal Bertrand.”[478]
Ligny, 17 June, 1815.
Not only is the tone of this letter altogether different from that of the verbal orders previously given, but the duty assigned to Grouchy is a wholly different one.
There is in the letter no trace of that certainty as to the position of affairs so plainly exhibited in the verbal orders. The news that a Prussian corps has been seen at Gembloux has evidently made a strong impression on the Emperor. It may very possibly indicate that Blücher is not falling back to Namur. The statement is twice made in the letter that the Emperor is in doubt as to the intentions of the Prussians, and the chief task now imposed upon Grouchy is to ascertain those intentions. The precise danger to be anticipated is stated explicitly. Grouchy is warned in so many words that the Prussians may be intending to unite with the English to try the fate of another battle for the defence of Brussels,—which was exactly what they were intending to do, and what they succeeded in doing. Whether they are or are not intending to do this, is the principal thing for Grouchy to find out. As the Emperor had previously informed Grouchy of his determination to fight the English “if they will stand on this side of the Forest of Soignes,”—which meant of course that he looked upon a battle with them the next day as very possible,—this question of the Prussians uniting with the English in fighting this battle was of vital importance to him.[479] What Grouchy was to do if he found the Prussians directing their movements so as to compass this end, it was left to him to determine for himself. It might be that he could hinder the accomplishment of their design most effectually by attacking them; it might be that his best course would be to rejoin the main army as soon as he could, or to manœuvre so as to act in conjunction with it. It was impossible for Napoleon to tell beforehand how things would turn out. Full discretion was therefore left to Grouchy to take whatever course might seem best to him.
Marshal Grouchy was making his arrangements to get his command under way when he received this letter. He experienced great delay in beginning his march to Gembloux. Vandamme did not get started till two o’clock. Gérard left Ligny an hour later. It came on to rain hard about two o’clock, and the roads soon became very bad. Grouchy did not succeed in getting farther with his two infantry corps that night than Gembloux, which is rather less than eight miles from St. Amand.[480] The cavalry of Exelmans was, however, stationed at Sauvenières, to gather information. Grouchy had with him a force of 33,319 men of all arms, of whom 4,446 were the cavalry belonging to the two corps of Pajol and Exelmans.[481] Napoleon took with himself Domon’s light cavalry division of the 3d Corps, but Grouchy retained that of Maurin, belonging to the 4th Corps,—say, 1,500 men. That is, he had 6,000 cavalry in all.
At ten o’clock that evening Grouchy wrote to the Emperor from Gembloux a letter[482] which seemed to indicate that he comprehended, at least to a certain extent, the nature of his task. He says that it appeared to him that the Prussians had passed through Sauvenières, where his (Grouchy’s) cavalry now have arrived, and that, at Sauvenières, they had divided into two columns, one taking the road to Wavre, by Sart-à-Walhain, and the other that to Perwez, a town on the way to Maestricht. Grouchy then goes on to say:—
“One may perhaps infer that a part is going to join Wellington, and that the centre, which is the army of Blücher, is retiring on Liége; another column with artillery has effected its retreat on Namur. Exelmans has been ordered to send this evening six squadrons to Sart-à-Walhain and three to Perwez.
“According to their reports, if the mass of the Prussians is retiring on Wavre, I shall follow them in that direction, in order that they may not be able to gain Brussels, and to separate them from Wellington.[483]
“If, on the contrary, my information proves that the principal Prussian force has marched on Perwez, I shall direct myself on that city in pursuit of the enemy.”