 The French army extended in a long line from the Danube to Lake Constance . The Third Division , commanded by Laurent de Gouvion Saint @-@ Cyr , positioned itself at the far left flank , and Dominique Vandamme 's detached force , returning from reconnaissance near Stuttgart , roamed on the north shore of the river . François Joseph Lefebvre commanded the Advance Guard , positioned on the slope below Pfullendorf , and Joseph Souham , with the Second Division , took position behind him . Pierre Marie Barthélemy Ferino 's First Division held the southern @-@ most flank , to defend against any encirclement by Charles ' force . Jourdan set up command at Pfullendorf , and the Cavalry <unk> , commanded by Jean @-@ Joseph Ange d 'Hautpoul , stood slightly to the north and west of Souham . 
