It was from this direction that the Serbian General Staff expected the first advance of the enemy. And yet there were dozens of other points where an attack in force was possible. Each must be covered with a force at least strong enough to hold the enemy back long enough to enable the forces stationed at the other points to come up to support. Here was the great advantage that the Austrians had to begin with; an advantage which the attacking army always enjoys. The attacking general alone knows where the first battle shall be fought. The Serbians, therefore, could not count on meeting the Austrians in full force before they could enter Serbian territory. They realized that they must give way at the first contact; that the Austrians would undoubtedly advance quite some distance within Serbian territory before enough Serbian forces could be brought up against them to make the opposition effective. Realizing this, it was decided to place fairly strong advance guards at all probable points of invasion with orders to resist as long as possible; until, in fact, defensive tactics could be adapted to the situation and the main Serbian army could be brought up to offer battle. However, two points stood out as the most probable. These were the two already mentioned; the north, along the line from Obrenovatz to Belgrade and to Semendria; or, the front Obrenovatz-Ratza-Losnitza-Liubovia. The first possibility had the advantage to the Austrians of offering the shortest route to the center of the country--the Morava Valley, their natural objective. But it also necessitated a difficult crossing of the Danube, which would have had to be preceded by the building of pontoon bridges. This would have given the Serbians time to move up their main forces. The second alternative, an invasion from the east, would have entailed a longer journey, but the advantage of natural covering and easy crossing made it a sounder plan. On July 28, 1914, the Serbians concentrated their forces in anticipation of either event. The outpost forces were stationed at or near Losnitza, Shabatz, Obrenovatz, Belgrade, Semendria, Pozarevatz and Gradishte. But their principal armies were centrally grouped along the line Palanka-Arangelovatz-Lazarevatz, while weaker, though important, detachments were stationed in the vicinity of Valievo, a branch railroad terminus, and Uzitze. This narrowed the field down to such limits that it was possible to march the troops from point to point, while the few railway facilities available were utilized for food and ammunition supplies. CHAPTER XLVIII AUSTRIAN SUCCESSES