ing a serious obstacle to
Von Mackensen's advance so long as the Russians could hold it. It was
imperative that they should be cleared out, but the task of carrying
it through was a difficult one. The undertaking fell to the Hungarian
troops of the Thirty-ninth Honved Division, who advanced to the attack
again and again only to be driven back each time by the Russian fire
from the heights. Big howitzers were called into play and soon
demolished the positions.

The Russians retired east of the Wistok, followed by Von Mackensen's
Austro-Hungarian corps, while the Prussian Guards moved on toward
Frysztak, where the Russian troops from the Tarnow sector had taken up
positions after the retreat from Brzostek.

On May 7, 1915, the Prussian Guards had passed over the railway at
Krosno, and at night fell upon the Russian lines east of the Wistok.
Particularly fierce encounters took place near Odrzykon and Korczina,
ten to fourteen miles southeast of Frysztak. A little farther westward
Von Mackensen delivered his main attack against the railway crossing
at Jaslo, which fell on the same day, May 7. The Russians retreated in
confusion with Von Mackensen close upon their heels. The whole defense
on the Wisloka collapsed, and nothing apparently could now save the
Dukla and those troops struggling through to escape from the net that
was gradually being tightened around them. Meanwhile, General Ewarts's
Army of the Nida, which formed the connecting link between the Russian
northern and southern armies, had fallen back above Tarnow to the
River Czarna in order to keep in touch and conformity with Dmitrieff's
shrinking line, which was now actually broken by the Wisloka failure.
The Russian position was extremely critical, for it seemed that the
German general would roll up the two halves and thereby inflict a
crushing and decisive defeat. General Ivanoff appears to have
recognized Von Mackensen's intentions in time to devise measures to
counteract the peril and save his left (Brussilov's army) from
disaster. By pushing forward strong columns from Sanok on the Upper
San to impose a temporary check upon the advancing tide, he gained a
brief respite for the troops entangled in the passes. To that sector
we will now turn to review the course of events.

On May 4, 1915, the Russians began to evacuate the positions they held
south of the range when Von Mackensen's extreme right approached
Krempna. Forging along at high speed the Germans an