Chattan fields that one. He steps over to a map that has been set up on an easel at the end of the room. The map depicts a swath of the Central Atlantic bordered on the east by France and Spain. "U-691’s last reported position was here," he says, pointing to a pin stuck in the lower left corner of the map. "She has been ordered back to Wllhelmshaven with her prisoners. She will go this way," he says, indicating a length of red yarn stretched in a north-northeasterly direction, "assuming she avoids the Straits of Dover."