Sarrail now advanced his men northward, along the west bank of the Tcherna, and next day he delivered an assault on the Mount of the Archangel, ten miles below Vozartzi. Here was the center of the Bulgarian positions, and here their lines must be pierced, if Babuna Pass was to be reached.
But not only was this position well fortified, but the Bulgarians were in superior force to the French. Moreover, as soon as Todoroff heard of what was going on, he hurried reenforcements to the Bulgarians on Mount Archangel. And this Sarrail knew; yet, without hesitation, he began the assault.
At the first attack the Bulgarian advance lines were driven out of the villages at the base of the mountain. The French continued their advance, and on November 10, 1915, they began a circling movement which resulted in the Bulgarians being squeezed out of Sirkovo, a village some distance up the mountain.
But by this time the Bulgarian reenforcements were beginning to arrive, and by the end of the second week of the month they began to take the offensive. They now had 60,000 men; against this force it was obviously impossible for the French to make any further headway.
The Bulgarian commander now showed that it was his intention to circle about the French, cut off their retreat by destroying the wooden bridge over the Tcherna in their rear, then pin them up against the mountain and pound them until they surrendered, all of which might have been accomplished by a more skillful general.
For three days a violent battle raged, in which the fate of the French army more than once hung in the balance, but superior military skill counted in the end. Possibly, too, the hearts of the Bulgarian soldiers were not in this fight, for the Bulgarian people have an almost reverential respect for the French. At any rate, they did not show here the same qualities that so distinguished them in the war against the Turks. At the end of the third day their lines began wavering, then broke. So completely were they routed that the French were compelled to bury nearly 4,000 of the dead they left behind. So close had the fighting been that at times the Bulgarian infantry charged the French positions to within a dozen yards, but in the last moment lacked the dash to carry them through the machine-gun fire and into the French ranks. At such moments the French would countercharge, whereupon the Bulgarians would turn and flee. Had the French been only a few thousand men stronger, they could have followed up their advantage, completely routed the Bulgarians, pushed their way across the mountains to Babuna Pass and so relieved the Serbians, as well as closing the gap through which the Bulgarians were yet to penetrate into Macedonia.
The French completed their victory on November 14, 1915; until the next day the Serbians held out, hearing the French guns, now loud and clear, then receding, hoping every hour to see them come streaming over the mountains to their aid. But the French could not do the impossible. The Bulgarians had been thrown back, but not crushed. Sarrail dared not leave that slender crossing over the Tcherna too far behind.
On November 16, 1915, the Serbians finally fell back from the pass on Prilep. The French, however, not knowing of the Serbian retirement at the time, continued to hold their advanced position at Mount Archangel until November 20, 1915, when the Bulgarians returned to give them fresh battle. And again the French were able to repulse their attacks, but further advance was now out of the question.
The situation of the Serbian armies up in the north was now truly desperate. The combined Austro-German and Bulgarian lines, beginning at Vishegrad, north of Montenegro, swept in a straight line across the heart of Serbia to Nish, where it curved downward to Vranya, then swept into Veles and down to where the French army prevented it from reaching the Greek frontier. It was, in fact, like a great dragnet, which had only to be contracted to sweep the Serbians inward, over against the awful defiles of the Montenegrin and Albanian Mountains, a country through which no organized army could pass in a body, and through which only the strongest of the noncombatants could hope to escape alive. And for a time it seemed as though the French would prick a hole through this net, through which, by rending it into a wide gap, the Serbians could have been saved. But with the retirement of Colonel Vassitch from Babuna Pass that last chance was gone; Serbia was left to her fate.
Meanwhile the pressure from the north continued irresistibly; steadily the Serbian armies were being pushed back against the mountain ranges, in comparison to which their own mountains were mere hills. And while the Serbians were waxing weaker every day, their enemies were growing stronger, not only because their long line was contracting, but because now they were being constantly reenforced. Also, with the cutting of the railroad, all means of supply were gone; the Serbians must now continue the fight with their own resources. They were now becoming woefully short, not only of ammunition, but of food as well. Yet they continued the struggle, retreating before the enemy facing them, step by step backward, taking advantage of every little natural position to cause the invaders as much loss as possible.