_January 6th._--At six in the morning the advanced guard of General Baumgarth's detachment started on march to Prunay, but the main body could not follow, since it was attacked in force at about half-past nine. With the object of observing the enemy, the infantry had been scattered in detached posts in a wide extension from Ambloy to Villeporcher, and only a small reserve remained at La Noue. The fight soon assumed greater expansion, and the defence with difficulty maintained the line Les Haies--Pias, the turning of the German left flank being seriously threatened, upon which the 6th Cavalry Division moved up, but could only enter the fight with one horse battery. The reserve, however, moved up along the high road to Chateau Renault and repulsed the enemy, who had already forced his way into Les Haies. But when he renewed the attack in strong columns and developed four batteries against the place, the reserve was obliged to retire behind the Brenne. Meanwhile the 16th Regiment, which had already reached Ambloy on its march to Vendome, turned back to St. Amand in support, and the just assembled 38th Infantry Brigade deployed between Neuve St. Amand and St. Amand with a strong force of cavalry on its flanks. But as by some mistake St. Amand was evacuated, Duke William of Mecklenburg (commanding 6th Cavalry Division) ordered a further retreat. The infantry, however, had already come to a halt at Huisseau and took quarters there. The advanced guard turned into Ambloy; the cavalry fell back partly on that place and partly on Villeromain. During the engagement about St. Amand the Xth Corps itself advanced on Montoire in two columns along the left bank of the Loire, leaving on its right a battalion in front of Vendome to secure the debouche of the IIIrd Corps through that place. When the 20th Division reached St. Rimay at about one o'clock, it found the heights on the opposite side of the Loir occupied by General Barry's troops. The massed German batteries were brought up to the southern ridge of the valley and soon drove the French off the broad flats; but the defile of Les Roches in the front remained quite unassailable. The broken bridge at Lavardin, lower down the stream, was therefore made practicable by the pioneers. The 19th Division having meanwhile reached that place, several battalions crossed from the south side to attack Les Roches, and easily dislodged the French. As darkness came on, preventing any further advance, the Corps found quarters in and about Montoire.