But Moreau, who appreciated the difficulties of forcing the passage of a large river in the face of an active enemy, believed that the risk was too great, and therefore refused to attempt the execution of Bonaparte's plan. Instead, he proposed the following plan. His left, under Ste. Suzanne, was to cross the Rhine at Kehl, and his centre, under St. Cyr, at Brisach. Both corps were to push forward, attack Kienmayer, and drive him into the defiles of the Black Forest. Moreau calculated that these attacks would lead Kray to believe that the French forces were massing in front of his right wing, and would cause him to re-enforce Kienmayer. Having driven the Austrians back into the Black Forest, and thus given the impression that the principal attack of the French would be made from the direction of Strasburg, Ste. Suzanne and St. Cyr were to withdraw suddenly. The former was to recross the Rhine at Kehl, ascend the river, cross again to the German side at Brisach, and take the position formerly occupied by St. Cyr; the latter was to make a flank march over the spurs and hills towards Schaffhausen by way of St. Blazien. Meanwhile Moreau with the reserve was to cross the Rhine at Bâle and march towards Schaffhausen, where, upon his arrival, his right, under Lecourbe, was to cross the river and join him. As soon as these movements were completed, Ste. Suzanne was to march towards Lake Constance by way of Friburg, Neustadt, and Loffingen. By this series of complicated manoeuvres, Moreau expected to unite the bulk of his forces in the vicinity of Schaffhausen, and to march thence against the flank of Kray in the Black Forest.