The news of this trespass on Prussian territory reached the ears of
Frederick William at a critical time, when the Czar sent to Berlin a
kind of ultimatum, intimating that, even if Prussia deserted the cause
of European independence, Russian troops must nevertheless pass
through part of Prussian Poland. Stung by this note from his usually
passive demeanour, the King sent off an answer that such a step would
entail a Franco-Prussian alliance against the violators of his
territory, when the news came that Napoleon had actually done at
Ansbach what Alexander had announced his intention of doing in the
east. The revulsion of feeling was violent: for a short space the King
declared he would dismiss Duroc and make war on Napoleon for this
insult, but in the end he called a cabinet council and invited the
Czar to come to Berlin.[29]

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 Donauwörth,
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