The corps led by Johann von Hiller (VI), Heinrich Graf von Bellegarde (I) and Prince Friedrich of Hohenzollern-Hechingen (II) were to converge upon Aspern, while Prince Franz Seraph of Rosenberg-Orsini (IV) was to attack Essling. Prince Johann of Liechtenstein's Austrian reserve cavalry was in the center, ready to move out against any French cavalry attacking the heads of the columns. During the 21st the bridges became more and more unsafe, owing to the violence of the current, but the French crossed without intermission all day and during the night.