stairs they ran to the Blackwells’ apartment, each girl eager to be the first to solve the mystery. Jo Ann’s long legs carried her ahead of Florence and Peggy, who arrived a moment later out of breath. There stood Jo Ann staring blankly at the solid plastered wall at the end of the hall. “I’m sure this is where that window ought to be,” she said finally in a perplexed tone. “There certainly isn’t any sign of one that I can see,” added Peggy, while Florence gazed silently at the spot where she thought the opening should be. Just then Juana ran in from the kitchen to see what had caused so much commotion in the silent old house. “Florencita! Que es [What is it?]?” she asked in alarm. “It’s nothing,” replied Florence in Spanish. Understanding the superstitious nature of the Indians, she thought it wiser not to tell Juana about this mysterious window for the present. Juana stared in shocked surprise. Something was wrong, she was sure. Young ladies of the best families did not deport themselves in such a manner. Her Florencita had never acted this way before—racing into the house like mad. Finally, shaking her head and mumbling to herself, she returned to the kitchen to finish her preparations for lunch. The moment she disappeared through the kitchen door, Jo Ann hastened through the one opposite and called to Florence and Peggy, “Come on, maybe we can see something from the window in this back room.” Much to their disappointment, the iron bars, set in the deep recess of the thick walls, prevented them from seeing anything except a part of the ruins of the old church directly across the narrow street. “And so the mystery deepens,” laughed Jo Ann. “I’ve heard of bumping your head against a stone wall, but I’ve never understood what it meant till now.” “Do you know what I think it is?” remarked Florence as they wandered back to the hall. “At one time there probably was an opening here”—she motioned toward the solid wall at the end of the hall—“then, sometime when they were fixing the house over, they closed it up. This house is very, very old, you know.” “But why would they leave a hole on the outside?” Peggy asked. “Oh, they probably didn’t think it mattered on that back street, and maybe the stones didn’t