There were two reasons for this caution. His Marshals found no very general disposition among the Poles to take up arms for France; and he desired not to offend Austria by revolutionizing Galicia and her districts south and east of Warsaw. Already the Hapsburgs were nervously mustering their troops, and Napoleon had no wish to tempt fortune by warring against three Powers a thousand miles away from his own frontiers. He therefore calmed the Court of Vienna by promising that he would discourage any rising in Austrian Poland, and he held forth the prospect of regaining Silesia. This tempting offer was made secretly and conditionally; and evoked no expression of thanks, but rather a redoubling of precautions. Yet, despite the efforts of England and Russia, the Hapsburg ruler refused to join the allies: he preferred to play the waiting game which had ruined Prussia.[122] The campaign was reopened amidst terrible weather by a daring move of Bennigsen's Russians westwards, in the hope of saving Danzig and Graudenz from the French. At first a screen of forests well concealed his advance. But, falling in with Bernadotte near the River Passarge, his progress was checked and his design revealed. At once Napoleon prepared to march northwards and throw the Russians into the sea, a plan which in its turn was foiled by the seizure of a French despatch by Cossacks. Bennigsen, now aware of his danger, at once retreated towards Königsberg, but at Eylau turned on his pursuers and fought the bloodiest battle fought in Europe since Malplaquet. The numbers on both sides were probably about equal, numbering some 75,000 men, the Russians having a slight superiority in men and still more in artillery. Driven from Eylau on the night of February 7th after confused fighting, the Muscovite withdrew to a strong position formed by an irregular line of hills, which he crowned with cannon.