"I wouldn't buy any book just now," said the master, seeing the drift of her thoughts. He went to one corner of the school-room, and, standing on the bench, pushed aside one of the boards laid loosely over the joists above. It was here, in the dark loft, that he kept the few articles not necessary to his daily existence in boarding 'round. Reaching his hand up above the boards, he found a copy of a school text-book on algebra, and brought it down with him, rapping it against his hand and blowing the dust off it. "Use that for a while," he said. "Oh, thank you!" said Barbara, taking hold of the book with a curious sense of reverence, which was greatly increased as she turned the leaves and regarded the symbols, whose nature and use were quite inconceivable to her. Here was a knowledge beyond any that she had ever dreamed of looking into; beyond that of any schoolmaster she had ever known, except Mason. "It looks hard," she said, regarding him. "Take it home and try it," he replied, as he took up his ruler to call the scholars to books. A closer companionship now grew up between the master and the pupil. Both of them anticipated with pleasure the coming of recess time, when the new study could be discussed together. Henceforth the boys looked in vain for Mason to take a turn with them in playing soak-about. To a man of high aims nothing is more delightful than to have a devoted disciple. Even the self-contained Mason could not be quite unmoved in contemplating this young girl, all of whose tastes and ambitions flowed in the same channel with his own, listening to him as to an oracle. If he had not been so firmly fixed in his resolve that he would not allow any woman to engage his affections before he had completed his college course, he might have come to fall in love with her. But all such thoughts he resolutely put aside. Of course, teaching her was a delight; but who could help feeling delight in teaching such a learner? Moreover, he was particularly fond of algebra. But he could hardly lay all of his enjoyment to his liking for algebra, or his pleasure in teaching a quick-witted pupil. He could not make himself believe that it was his enjoyment of algebraic generalizations that made his hand tremble whenever he returned a slate or book to Barbara Grayson. Barbara, for her part, was too intent on her work to think much about anything else. She had more than once caught sight of the furtive, inquiring glance of her teacher on her face before he could turn his eyes away; she was pleased to note that his voice had a tone in addressing her that it had not when he spoke to the others; and she took pleasure in perceiving that she was beyond question the favorite pupil. But Barbara was averse to building any castles in the air which she had small chance of being able to materialize.