Three days before the fall of Przemysl the Russians abandoned the defensive and commenced a vigorous attack on the Carpathian front. Active preparations for the advance had been completed when the capitulation of the fortress was to be expected any hour. Having so far held the Germanic armies in check, it was necessary for the Russians to regain complete control of the Carpathians and the passes before the snow should begin to melt, especially if they decided on an invasion of Hungary. On the other hand, before any offensive could be undertaken against the Germans in Poland, or the Austrians at Cracow, it was imperative to secure the southern flank in Galicia. They had by this time partially grasped one particular feature of German strategy, namely, to parry a blow from one direction by striking in another. A further consideration may have been the absolute certainty that Germany would dispatch more reenforcements to the aid of her ally. Selivanoff's siege army was distributed between Dmitrieff, Brussilov, and Ivanoff, but they could not be employed to full advantage owing to the restricted area presented by the Germanic front. Being largely composed of siege artillery as well as cavalry, a considerable portion of Selivanoff's army was unsuited for mountain warfare. Cavalry were converted into infantry, but could not be supplied with the necessary equipment; they had no bayonets, and most of the fighting was hand-to-hand. Great masses of Germanic reserves were concentrating in northern Hungary, into which the Russians had driven a thin wedge south of Dukla, where they held an isolated outpost near Bartfeld. To leave this position undeveloped meant compulsory withdrawal or disaster. With the continual influx of reenforcements on both sides, the struggle for the main passes gradually develops into an ever-expanding and unbroken battle front: all the gaps are being filled up. From Dukla westward to the Dunajec-Biala line and the Carpathian foothills a new link is formed by the Fourth Austrian Army, commanded by the Archduke Joseph Ferdinand, with two and a half army corps and one German division. In the Central Carpathians a fifth army, under the command of the Austrian General von Bojna, appears between the forces of Boehm-Ermolli and those of Von Linsingen. Right away eastward the purely Austrian army of Von Pflanzer-Baltin was holding the Pruth Valley. The Germanic chain was complete, with every link welded together.