This was the shot they heard at head-quarters in Thamsbrück. The regiment withdrew, constantly skirmishing with the enemy, and fell back slowly upon Langensalza. In the meantime the town was abandoned, the order of the general in command ran, "that the army whilst fighting should retreat." At Langensalza the dragoons fell in with the infantry of the Knesebeck Brigade, which had received orders to retire behind the Unstrut. The troops obeyed this order with gnashing of teeth, and gave up one position after the other, for the enemy forthwith to seize upon; the enemy's riflemen harassed them, and the artillery advancing along the heights opened a nearer and more murderous fire. The dragoons crossed the bridge over the Unstrut, and made a stand before the village of Merxleben, on the slope of the Kirchberg hill, from whose summit a Hanoverian battery maintained a fire, which, though less rapid than the Prussian, was so well directed that it did great execution in the hostile ranks. To the right of the dragoons, General Knesebeck's brigade was massed, he having followed the command he had received to retire. On the other side of the Unstrut stood a mill, upon a small stream called the Salzabach; immediately after the retreat of the Hanoverians it was occupied by the Prussians, and from it they kept up a heavy fire. Two battalions of the guards marched past the dragoons. At the head of the first rode Lieutenant-Colonel von Landesberg; the second was led by Colonel von Alten. The battalions had crossed the Unstrut, and were following the order received to retire to the brigade stationed on the hill. Colonel von Landesberg rode thoughtfully in front of his battalion, the grenadiers followed him in solemn silence. The battalion had the Unstrut on the left, and had just reached a spot where it was forced to turn to the right, to take up the prescribed position. At this place the banks of the river are very low, and it is so shallow that it is easy to cross it. A level terrace surrounds the hill, upon the slope of which lies the village of Merxleben. The enemy's most advanced chain of skirmishers was approaching the opposite bank of the river. Colonel von Landesberg gave a searching look at the situation. "If this spot remains undefended," he said to his adjutant, "the enemy will penetrate our position, and divide our forces." "So it seems to me, colonel," replied the adjutant. "I cannot see why it is to be abandoned,--however, the general staff--" The colonel gnawed his moustache. "It is impossible to give up this position to the enemy," he said, half to himself. His eyes flashed, and he pulled in his horse suddenly. "Battalion, halt!" he shouted. The command was repeated along the ranks; the battalion halted. With excited faces the grenadiers awaited further orders from their leader. "Right about turn!" he cried. A thundering shout of joy broke as from one mouth along the ranks, and in an instant the grenadiers had fronted.