But there were two remarkable circumstances by which Napoleon virtually acknowledged that he had received an unusual check. On the 13th February, four days after the battle, a message was despatched to the King of Prussia by Buonaparte, proposing an armistice, on grounds far more favourable to the Prince than those Frederick William might have been disposed to accept, or which Buonaparte would have been inclined to grant, after the battle of Jena. It was even intimated, that in case of agreeing to make a separate peace, the Prussian King might obtain from the French Emperor the restoration of his whole dominions. True to his ally the Emperor of Russia, Frederick William, even in the extremity of his distress, refused to accede to any save a general peace. The proposal of an armistice was also peremptorily refused, and the ground on which it was offered was construed to indicate Buonaparte's conscious weakness. Another decisive proof of the loss which Napoleon had sustained in the battle of Preuss-Eylau, was his inactivity after the battle. For eight days he remained without making any movement, excepting by means of his cavalry, which were generally worsted, and on the 19th February he evacuated the place, and prepared himself to retreat upon the Vistula, instead of driving the Russians, as he had threatened, behind the Pregel. Various actions took place, during his retreat, with different fortunes, but the Russian Cossacks and light troops succeeded in making numbers of prisoners, and collecting much spoil. [Sidenote: DANTZIC.] The operations of Napoleon, when he had again retired to the line of the Vistula, intimated caution, and the sense of a difficult task before him. He appeared to feel, that the advance into Poland had been premature, while Dantzic remained in the hands of the Prussians, from whence the most alarming operations might take place in his rear, should he again advance to the Vistula without subduing it. The siege of Dantzic was therefore to be formed without delay. The place was defended by General Kalkreuth to the last extremity. After many unsuccessful attempts to relieve it, Dantzic finally surrendered in the end of May 1807, after trenches had been opened before it for fifty-two days.[273] If the season of the year had admitted, a British expedition to Dantzic might, if ably conducted, have operated in the rear of the Emperor Napoleon the relief of Prussia, and perhaps effected the liberation of Europe.