Trying the door, it was found to be locked, as she had expected it would be, but the windows were neither barred nor locked. Grace cautiously threw one open and looked eagerly out. The moon, somewhere back of her to the eastward, was in the sky and lighted up the valley before her, though none of the light penetrated the room. Before her lay a village, two villages in fact, but it was the one on the opposite side of the river that most interested her, and Grace studied its outlines in the moonlight for some time. “I believe that is Coblenz,” she muttered. “This building is a castle and I am up in the air for certain. There is no necessity to bar these windows, for they know I can’t get down from here unless I fall down. I wonder why they wish to keep me a prisoner?” Grace pondered over this for some time, going over all that had been said to her by the German woman and what she had heard the man and woman say to each other in their own language. “It seems to resolve itself to this,” she decided. “Some one of the name of Rosa von Blum has warned them that an important woman was in a drifting balloon headed their way. Now this Rosa person must be somewhere in the American lines. It is my idea that this Rosa is a man. That would be just like a Hun scheme. Perhaps the word came by the pigeon route. The more I think of the pigeon incident the more convinced am I that a Chinaman is mixed up with it. Won Lue is the key to that mystery, and with that key I shall yet unravel the pigeon mystery. So much for that. To-morrow morning they will get another pigeon message unless some one shoots down all three of the birds, and that message will tell them who I am. The war being ended will they dare take their revenge on me now for exposing Madame de Beaupre and André? They will! Trust a Hun not to have sense enough to realize that he too will have to pay the price.” Grace pondered for a long time. “I am glad I woke up and have had time to think this matter over. I shall know how to conduct myself to-morrow when they speak my name. Of one thing I am glad. I am facing Coblenz, and sooner or later I may be able to attract the attention of some one who will be interested in what I have to say, though they will probably move me to some other less convenient room before the Americans arrive. Our troops should be at the Rhine to-morrow afternoon. To-night they will be but twelve miles from here, and even now an advance guard may be in the city. At least there are American intelligence officers there. I wonder where they have stowed the major away?” She sighed and concluded to go back to bed, knowing that she would be in need of all her strength for what might be before her on the morrow.