General GROLMAN, the Quartermaster General of the Prussian Army, foreseeing the consequences of the Line having been thus broken by the Enemy, hastened to Bry, and desired General PIRCH II. to cover the retreat by means of the troops here collected together. He then proceeded in the direction of Sombref, and finding near this place two Battalions of the 9th Regiment (Sixth Brigade) he posted them in rear of a hollow road, leading from Bry towards Sombref. These Battalions had, in their retreat from Ligny, defeated several attempts on the part of the Enemy's Cavalry to break them. GROLMAN, on perceiving a twelve pounder had stuck fast in this hollow road, ordered the Battalions to advance again in front of the latter, to assist in extricating the Battery, and to protect its retreat; which was immediately accomplished within view of the French Cavalry. It was at this critical period of the battle, that the 2nd Battalion of the 1st Westphalian Landwehr, which still continued in reserve, in rear of Bry, under the command of Captain GILLNHAUSSEN, appeared upon the Height in front, where it particularly distinguished itself. In the first place it succeeded in effectually checking, by its vigorous fire, the French _Cuirassiers_, who were in pursuit of the Prussian Infantry. Then it drove back French Cavalry which was on the point of making a fresh attack upon the Prussian Dragoons. Afterwards it successfully withstood three charges by the French Cavalry of the Guard. General GROLMAN now ordered this Battalion to join the 9th Regiment near Sombref; and, with the latter, to take up a position at the junction of the cross road from Ligny with that from Bry to Sombref. This position, which was in rear of the before mentioned hollow road, was maintained until past midnight. * * * * * Such were the circumstances resulting from the French having forced the Prussian Line at Ligny, and pursued in the direction of Bry: it is now necessary to explain what occurred at that time, at, and in the vicinity of, Sombref. The First Brigade, which had been placed in reserve, was ordered to take post, in Squares, upon the high road to Sombref, to check the pressure of the Enemy's Cavalry. Subsequently, when the direction of the retreat was decided upon, it fell back upon Tilly. The Fourth Brigade, with the exception of one or two Battalions, advanced again through Sombref towards Ligny, just as the French Cavalry pushed towards the high road. The Battalions of the Brigade formed Squares, and fell back upon the high road, whence they continued their further retreat.