They had just turned the corner of a street lined with what appeared to Sally to be rather imposing houses. It was a highly respectable street, like the others they had come through, and it was very quiet and dignified. Indeed, there was no one in sight except Professor Ladue, who was sauntering along with the manner of the care-free. His coat was unbuttoned and blowing slightly, although there was that chill in the air that always precedes snow and the wind was rising. Their steps echoed in the quiet street, and, instinctively, they walked more softly. Strangely enough, they all seemed to have the same feeling; a feeling that the professor might suddenly vanish if he heard them and looked around. "Now, Sally," Fox continued, speaking somewhat hurriedly, "you run and catch him before he turns that next corner. The street around that corner is only a court with a dozen houses on it. If you don't catch him before he goes into the house in the middle of that block, give it up. Don't try to go in after him, but come back. Henrietta and I will be waiting for you. If you get him, we won't wait. But don't say anything about our being here unless he asks you. He might not like to know that I had followed him." "But," protested Sally, bewildered, "aren't you going with us? I thought you were going shopping with us." "If we had caught him before he had left the college. Now, it might be embarrassing--to both your father and to me." "But your tickets!" wailed Sally in a distressed whisper. They had been speaking like conspirators. Fox laughed softly. "I have a few cents about me. You can make that right some other time. Now, run!" So Sally ran. She ran well and quietly and came up with her father just after he had turned that last corner. The professor must have been startled at the unexpectedness of the touch upon his arm, for he turned savagely, prepared, apparently, to strike. "Father!" cried Sally; but she did not shrink back. "Father! It's only me!" The look in Professor Ladue's eyes changed. Some fear may have come into it; a fear that always seemed to be latent where Sally was concerned. His look was not pleasant to see directed toward his own little daughter. The savage expression was still there, and a frown, denoting deep displeasure. "Sally!" he exclaimed angrily. Then he was silent for a time; a time, it is to be presumed, long enough for him to collect his scattered faculties and to be able to speak as calmly as a professor should speak to his daughter, aged ten. "Sally," he said at last, coldly, "may I ask how you came here?" "Why," Sally replied, speaking hastily, "I was coming in town, this afternoon,--I planned it, long ago, with mother,--and--" "Is your mother with you?" the professor interrupted. To a careful observer he might have seemed more startled than ever; but perhaps Sally was not a careful observer. At all events, she gave no sign.