But he now urged the need of instantly marching away to the north with all available forces.

Still Mack clung to his notion that it was the French who were in sore straits; and he forbade the evacuation of Ulm; whereupon the Archduke, with Schwarzenberg, Kollowrath, Gyulai, and all whose instincts or rank prompted and enabled them to defy the madman's authority, assembled 1,500 horsemen and rode off by the northern road.

It was high time; for Ney, firmly established at Elchingen, was pushing on his vanguard towards the doomed city: Murat and Lannes were charged to support him on the north bank, while across the river Marmont, and further south Soult, cut off the retreat on Tyrol.
At last the scales fell from Mack's eyes.

Even now he protested against the mere mention of surrender.

But again he was disappointed.
Ney stormed the Michaelsberg north of Ulm, a position on which the Austrians had counted; and on October 17th the hapless commander agreed to terms of capitulation, whereby his troops were to march out and lay down their arms in six days' time, if an Austro-Russian army able to raise the siege did not come on the scene.