A violent bombardment began on June 12, 1915, and Austro-Hungarian troops crossed the river and occupied both Sieniava and Piskorovice. Next day the advance spread along the whole line, extending from Tarnoviec on the Zlota to the Radymno-Javorov road, pressing north and eastward against the Russian front. Pivoting on Sieniava, Von Mackensen swung his right toward Mosciska, which Von Marwitz captured on June 14, 1915. The same night the Archduke Joseph Ferdinand's entire army was slowly wheeling from the San toward the Tanev, facing due north. On June 16, 1915, the left of this line was already inside the borders of Russian Poland, and its right wing along the entire Tanev front. By June 16 numerous towns and villages were taken by the Germans. The Wolff Telegraphic Bureau announced that Von Mackensen's army had captured 40,000 men and 69 machine guns, which undoubtedly referred to all the Galician groups, for on June 12, 1915, Von Mackensen had "replaced" the Archduke Frederick as generalissimo of the Austro-Hungarian armies. The "phalanx" was pressing against Rawa-Ruska, Magierow, and Janov; Boehm-Ermolli against Grodek, part of which he captured by a midnight assault on June 16. In five weeks the Russian line or front in Galicia had shrunk from 300 miles to about 100. Before Dunajec, when it was united with the northern groups, it had represented the longest battle line in the history of the world. The Russians began to evacuate Lemberg about June 17, 1915, the day Von Mackensen's right entered Javorov. On the 19th his advance guard was approaching Rawa-Ruska. Boehm-Ermolli was meanwhile undergoing severe punishment near Komarno, where an Austrian advance force endeavored to get through the Grodek Lakes. The Russian artillery drove them back; for three days there were furious bayonet and cavalry charges and countercharges; despite the most terrific bombardments the Austrian attacks were broken by the desperate Russians. On this occasion, at least, the Russians were well supplied with shells hurriedly sent by rail from Kiev, which enabled them to repulse the Austrians on the lakes. Boehm-Ermolli is said to have lost half of his effectives in his attempt to penetrate through Grodek and Dornfeld, fifteen miles south of Lemberg.