From time to time news came of this or that group of nurses or doctors who had joined the retreat, had been taken prisoner, or on their own had reached safety; but Reuben Cowder could get no clew to Nancy's whereabouts, though he worked day and night, interviewing every returning soldier or civilian of whom he heard, sending agents to Salonika and to Corfu to search. It was not until the opening of the year 1916 that news came to him that he trusted. This was when three of his daughter's companions in the Serbian unit reached London. They brought him the first trustworthy report of what had happened to Nancy when the invasion began, and while they could give no assurance that she was still living they at least left him the hope that this might be true. How improbable the girls felt this to be, they took care not to let the distracted man know. Their story, so far as it interested Reuben Cowder, was soon told. The approach of the Austro-Hungarians from the north and the Bulgars from the west had begun the middle of October. The Serbians, who, through the months since the first invasion, had been accumulating stores and preparing for a second attack, welcomed the enemy, confident of their ability to drive him back. Their confidence was quickly destroyed. The mass thrown against them was overpowering. Nish was taken early in November by the Bulgars, while by the middle of the month the army from the north was sweeping Valievo. Nancy's unit, unable to believe that they were in danger and unwilling to desert now that every day was multiplying the wounded, remained at their posts until the population was ordered out. They quickly determined not to abandon the fleeing people. They would go with them, a traveling unit. Two great ox carts were secured, and their stores and a few of the most helpless patients loaded into them. Two native women who had become particularly useful were taken, and thus equipped these dauntless young women voluntarily threw themselves into the great river of Serbs flowing southward.