Why the head lady had taken such a very evident dislike to her, Bobs could not understand, for surely she was willing to do whatever she was told. Ah, well, she wasn't going to worry. "Worrying is what makes one old," she thought, as she mounted a small step-ladder on casters that one could push along the shelves. From the top of it she examined the books that were highest. Suddenly she uttered an exclamation of delight, then looked about quickly to be sure that she had not been heard. Customers in the front part of the store occupied the attention of the three clerks, so Roberta reached for a volume that had attracted her attention. It was indeed rare and old, so very old that she wondered that the covers did not crumble, and it had illumined letters. "Perhaps they were made by early monks," Bobs was thinking. She sat down on the ladder and began turning the fascinating pages that were yellow with age. Suddenly she was conscious that someone stood near her. She looked up to find the accusing gaze of the head clerk fixed upon her.