In the first weeks of the war, when the great offensive movement of the Austrian army toward Lublin was crushed by the Grand Duke Nicholas, and the broken hosts of the Dual Monarchy were sent flying through Galicia and the Carpathians, a cloud of Cossack cavalry followed them and penetrated into the plains of Hungary. This last operation was merely a raid, however, and the Cossacks were soon galloping back through the mountain passes. Then the Russians laid siege to Przemysl, and occupied the whole of Galicia up to the line of the San. Later they pushed on westward to the Dunajec, threatening Cracow. This was their high tide. On their left flank was the mass of the Carpathians, pierced by a number of passes. The more important of these, from west to east, are the Tarnow, Dukla, Lupkow, and Uzsok. [Sidenote: The Carpathian passes.] The Austrians were rallied after some weeks, and put up something of a fight for these "contracted places." The Russians, following the precepts of Bourcet, threatened the passage which seemed most desirable, because of the railroad facilities, and delivered a heavy blow at the Dukla Pass, the least important of the four. Here they pushed through to Bartfeld, on the Hungarian plain. Then, however, Mackensen's fearful blow smashed the Russian line on the Dunajec and poured the German legions across Galicia in the rear of the Carpathian armies, forcing the Muscovites to abandon the passes and scurry home. [Sidenote: Plains more often battlegrounds.] Mountain warfare has always had a certain romantic glamour, and it has filled many pages in the literature of fighting. As a matter of historical fact, however, it has played a comparatively small part in the world's annals. Almost all the great campaigns have been fought out in the lowlands. It is Belgium, for instance, and not Switzerland, that has been proverbially the battle-ground of Europe. Napoleon and Suwaroff marched armies through the Alps, but only as a means of striking unexpectedly at the enemy who occupied the plains beyond. Up to the time of the present war, mountain campaigns have usually been no more than picturesque foot-notes to history, illuminated by the valor of raiding clansmen like Roderick Dhu of the Scottish Highlands, or guerrilla chiefs like Andreas Hofer, the Tyrolese patriot. Hofer's struggle against Napoleon was indeed a gallant and notable one, but it scarcely entered into the main current of history. [Sidenote: Garibaldi's mountain campaigns.]