The German Fifth Army made a final major attack on 10 September, running into heavy fire from the soixante-quinzes ("black butchers" as the Germans called them) of Micheler’s V Corps and Verraux’s VI corps. Moltke, increasingly concerned at the failure of the German attacks at Nancy, initially rescinded his permission for the final night attack until Wilhelm threatened to appeal to his father again. In the first ten days of September the German Fifth Army suffered 15,000 casualties, with some units suffering up to 40% officer casualties. At 9am on 10 September Lt-Col Hentsch, returning from ordering von Kluck and von Bülow to fall back from the Marne at the west of the German line, ordered Fifth Army to retreat also, an order which Wilhelm and his chief of staff Schmidt von Knobelsdorff refused to obey unless received in writing from the Kaiser or from Moltke. That day Sarrail was able to signal Joffre "situation satisfactory", whilst at 2pm Joffre was able to inform Millerand (War Minister) that the Battle of the Marne was now an "incontestable victory".