Her suspicions were still further confirmed when she heard the voices of Mrs. Smythe and Miss Marshall in conversation with the doctor in his apartment that evening. They were making merry and Madame was actually laughing. When Grace discovered that they were discussing subjects that she knew were of military value she was horrified that Mrs. Smythe could so far forget herself, but what to do about it she did not know. Grace felt that she should take the matter to Captain Boucher, yet she could not quite bring herself to carry tales about the woman she did not like. It looked petty to her, beneath her, so Grace decided to await developments and continue with her work. That night as she lay wide awake in her bed, she heard the doctor go to the cellar. She heard him fix the furnace for the night; then the sound of distant conversation floated up to her. After a time the doctor came up and the house settled down to silence. This same thing, so far as the cellar excursion was concerned, continued for three nights. During that time Grace did not get much sleep. Much of the time, after Elfreda went to sleep, Grace spent sitting in a chair tipped back against the wall where she appeared to be resting in profound thought. On the third night she was aroused by an alarm of fire in the street. She did not learn the cause of it until the following morning, when she was informed that the fire had been discovered in the basement of the main barracks, where nearly a thousand American soldiers were sleeping. Grace asked few questions about this blaze, though in the light of what she already knew she had certain well-founded suspicions. The next night nothing occurred to disturb the Army of Occupation, though Grace Harlowe increased her rapidly enlarging fund of information to an extent that alarmed even her. She saw that she must turn over some of it to the Intelligence Department without delay. Human lives depended upon her doing so. It was too late to do so that night, for to leave the place might upset all her plans were she discovered. After pondering over the subject from all angles the Overton girl went to bed. How she did wish she might confide in Elfreda Briggs. Grace, however, had learned that in these secret matters there was but one safe course--to keep one’s own counsel. Well-intentioned as those in whom one confided might be, there was always the possibility of a word slipping out, of a facial expression or of an unconsciously antagonistic attitude toward the wrong person. “Dear Elfreda shall know all that I know after I have completed my work. I must confess to myself that it is the most interesting work I have ever done, this pitting one’s wits against some of the keenest ones in Europe. However, I still have some distance to go before I arrive at my objective.” These thoughts and many others drifted through Grace Harlowe’s mind before she got to sleep.