Once across the river, the two Russian corps crossed the upper reaches of the River Boog and so approached the town of Lemberg from the east. The main Austrian army, however, had by this time moved up to bar the further advance of the Russian forces, and the whole of their armies on the left bank of the River Vistula being in front of the three Russian corps, the latter were compelled to adopt a defensive rôle for three or four days, after which, having received large reinforcements, the Russian force moved forward and drove the Austrian troops out of their entrenchments outside Lemberg at the point of the bayonet. A desperate attempt was made by means of a counter-attack to arrest the advance of the Russian troops, but this only resulted in the capture of 6,000 Austrian prisoners. [Illustration: WHERE RUSSIA FIGHTS. Battle grounds of Eastern Prussia and of Galicia, where the Austrians were repeatedly defeated with heavy losses.] Lemberg was not a fortress but was recently converted into a semi-fortified place, as a series of lunettes, redoubts, etc., had been hastily prepared. It was the headquarters of the 11th Austrian Corps, which consisted of the famous 43rd Landwehr infantry division, and was further divided into three Landwehr brigades. There was also a Landwehr Uhlan regiment, together with a howitzer division of field artillery. These batteries were armed with 10.5-centimeter guns, fitted with the German or Krupp eccentric breech action. The forts outside the town were said to be armed with the 15-centimeter siege gun made of steel, also with a Krupp action. The ammunition for these guns is chiefly high explosive shell and shrapnel; one of the forts is also said to have had a battery of three 24-centimeter heavy siege guns of quite a modern pattern. GERMANY RUSHES REINFORCEMENTS When Lemberg fell the Russian advance covered a line extending from far up in Eastern Prussia, near Tilsit, across the frontier and on down south into Austrian Galicia. Königsberg was hearing the sound of the Russian guns and its besiegers seemed on the verge of victory. A central column of mighty strength was pushing its way into Germany, despite a stubborn resistance. Then the tide turned. German reinforcements were brought up and under General von Hindenberg the Germans administered a severe defeat to General Rennenkampf's army near Allenstein, in which it was claimed that 60,000 prisoners were taken. Other reverses were suffered by the Russians and soon after the middle of September they had been forced to retire from German territory, the German troops following them into Russia, where a series of minor engagements occurred near the frontier. GENERAL RENNENKAMPF'S DEFEAT The operations leading to the defeat of General Rennenkampf's Russian army by the Germans were as follows: