Rennenkampf instantly followed him up, and by flinging his left well south towards the valley of the Bobr, endeavoured to cut off the German forces between Augustovo and the causeway leading to Suwalki. He had to push through the Forest of Augustovo, a region much like that in which von Hindenburg had destroyed Samsonov's army. Guided by the foresters of the district, his men slowly threaded the matted woods, and by 1st October had seized Augustovo. For two days there was a fierce rearguard action in the woods, and the Germans lost heavily in guns and prisoners. Rennenkampf claimed that 60,000 Germans had been killed, wounded, or captured; and if his estimate is correct, he had fully revenged Tannenberg. Von Hindenburg, however, managed to get the bulk of his force away, and by 9th October they were all back again in East Prussia, whither Rennenkampf could not follow them without the risk of being entrapped in the woods and lakes and marshes where Samsonov had suffered disaster in the last days of August. [Illustration: "Three Emperors' Corner." _Photo, Central News._ Here three empires meet--the German, Austrian and Russian--three empires that between them hold sway in Europe over more than 375 millions of people, Teutonic and Slav, and exercise authority over nearly 2½ million square miles of territory--about two-thirds of the whole continent. In the foreground is seen a portion of German Silesia, on the right is Austrian Galicia, and in the background Russian Poland. The broad river is the Prgemeza; the smaller river is a tributary which here separates Austria from Russia.] Von Hindenburg's great advance to the Niemen had failed. It had achieved nothing; and meanwhile, as we shall soon hear, the Russians were advancing towards Cracow, and were drawing nearer and nearer every day to Silesia. A great effort had now to be made to check them, and von Hindenburg was ordered southward to undertake the task. * * * * *