While the Gallophil counsellors, Haugwitz and Lombard, were using all their arts to hinder the Prusso-Russian understanding, the meshes were being woven fast around Mack and the Archduke Ferdinand.  Bernadotte’s corps, after making history in its march, was detached to the south-east so as to hold in check the Russian vanguard, and to give plenty of room to the troops that were to cut off Mack from Austria, a move which may be compared with the march of Bonaparte to Milan before he essayed the capture of Melas.  Both steps bespeak his desire to have ample space at his back before circling round his prey.

On October 6th the corps of Soult and Lannes, helped by Murat’s powerful cavalry, cut the Austrian lines on the Danube at Donauwoerth, and gained a firm footing on the right bank.  Over the crossing thus secured far in Mack’s rear, the French poured in dense array, and marched south and south-west towards the back of the Austrian positions, while Ney’s corps marched to seize the chief bridges over the Danube.

A study of the processes of Mack’s brain at this time is not without interest.  It shows the danger of intrusting the fate of an army to a man who cannot weigh evidence.  Mack was not ignorant of the course of events, though his news generally came late.  The mischief was that his brain warped the news.  On October 6th he wrote to Vienna that the enemy seemed about to aim a blow at his communications:  on October 7th, when he heard of the loss of Donauwoerth, he described it as an unfortunate event, which no one thought to be possible.  The Archduke now urged the need of an immediate retreat towards Munich, and marched in an easterly direction on Guenzburg:  another Austrian division of 8,000 men moved on Wertingen, where, on October 8th, it was furiously attacked by the troops of Murat and Lannes.  At first the Imperialists firmly kept their ranks; but the unequal contest closed with a hasty flight, which left 2,000 men in the hands of the French Then Murat, pressing on through the woods, cut off Mack’s retreat to Augsburg.  Yet that general still took a cheerful view of his position.  On that same day he wrote from Guenzburg that, as soon as the enemy had passed over the Lech, he would cross the Danube and cut their communications at Noerdlingen.  He wrote thus when Ney’s corps was striving to seize the Danube bridges below Ulm.  If Mack were to march north-east against the French communications it was of the utmost importance for him to hold the chief of these bridges:  but Ney speedily seized three of them, and on the 9th was able to draw closer the toils around Ulm.