While immersed in this prodigious task, the Emperor heard, with some surprise but with no dismay, the news of Prussia's armaments and disaffection. At first he treats it as a passing freak which will vanish with firm treatment. "Remain at Berlin as long as you can," he writes to Eugène, March 5th. "Make examples for the sake of discipline. At the least insult, whether from a village or a town, were it from Berlin itself, burn it down." The chief thing that still concerns him is the vagueness of Eugène's reports, which leave him no option but to get news about his troops in Germany from _the English newspapers_. "Do not forget," he writes again on March 14th, "that Prussia has only four millions of people. She never in her most prosperous times had more than 150,000 troops. She will not have more than 40,000 now." That, indeed, was the number to which he had limited her after Tilsit; and he was unable to conceive that Scharnhorst's plan of passing men into a reserve would send triple that force into the field.[287] As for the Russians, he writes, they are thinned by disease, and must spread out widely in order to besiege the many fortresses between the Vistula and the Elbe. Indeed, he assures his ally, the King of Bavaria, that it will be good policy to let them advance: "The farther they advance, the more certain is their ruin." Sixty thousand troops were being led by Bertrand from Italy into Bavaria.[288] These, along with the corps of Eugène and Davoust, would crush the Russian columns. And, while the allies were busy in Saxony, Napoleon proposed to mass a great force under the shelter of the Harz Mountains, cross the Elbe near Havelberg, make a rush for the relief of Stettin, and stretch a hand to the large French force beleaguered at Danzig. Such was his first plan. It was upset by the rapidity of the Cossacks and the general uprising of Prussia. Augereau's corps was driven from Berlin by a force of Cossacks led by Tettenborn; and this daring free lance, a native of Hamburg, thereupon made a dash for the liberation of his city. For the time he was completely successful: the fury of the citizens against the French _douaniers_ gave the Cossacks and patriots an easy triumph there and throughout Hanover. This news caused Napoleon grave concern. The loss of the great Hanse Town opened a wide door for English goods, English money, and English troops into Germany. It must be closed at all costs: and, with severe rebukes to Eugène and Lauriston, who were now holding the line of the middle Elbe, he charged Davoust (March 18th) to hold the long winding course of that river between Magdeburg and Hamburg. The advance of this determined leader was soon to change the face of affairs in North Germany.