Davout was crossing the river Saale about six o'clock in the morning of the fourteenth, and was well over with about two thirds of his corps, when suddenly his advance-guard found itself facing a portion of the enemy at the hamlet of Hassenhausen. It was the Prussian van. At first the thick mist concealed the armies from each other, but Davout hurried his columns forward and deployed them by the right for a simultaneous attack; those of the Prussians advanced and deployed so slowly that they came into action successively and lost the advantage of their superior numbers. The action began by a charge of Blücher's cavalry against the French right; but the men, unable to withstand the steady fire of the French infantry, recoiled and fell back in confusion. The Prussian right then moved around the French left by the flank, and drove their opponents into the village for shelter. They could not, however, dislodge them, and were left standing in the open field for two hours under a murderous fire. By this time it was noon; Davout's last companies had crossed the river, and the brave general, putting himself at their head, charged with them at double quick. The Duke of Brunswick fell, blinded in both eyes and mortally wounded; the King, though intervening with energy, could not keep the troops in line. At the same time his left was also attacked by a fresh force, and he determined to fall back on the reserve, which, owing to Brunswick's disability and consequent failure to give the necessary orders, had remained stationary in the critical moment at Gernstädt. The French followed, and the running fight continued through and beyond Auerstädt, until at five in the evening Davout called a halt. Frederick William did not, as was entirely possible, turn back with the reserve and strive to overwhelm his exhausted foe, but marched onward, expecting to unite with Hohenlohe and renew the conflict next day at Weimar.