There was a little knoll at one end of the orchard, and there was a very old gnarled apple-tree at the edge of the knoll. If Sibyl ran fast she could climb into the apple-tree and look right down on to the common. No sooner did the thought come to her than she resolved to act on it. Knowledge is always power, and she need not tell Fanny anything at all unless she liked. She could be faithful to poor Betty, who was in disgrace, and at the same time she might know something about her. It was so very odd that Betty was expelled from the Specialities. She could not possibly have resigned, for had she done so there would have been a great fuss, and everything would have been explained to the satisfaction of the school; whereas that mysterious sentence on the blackboard left the whole thing involved in darkest night. What had Betty done? Had she really told a lie about what she had found in the old stump of oak? Was it not a piece of wood after all? Had she really sent Sibyl into the flower-garden to gather marguerites and make herself a figure of fun at the Specialities' entertainment? Had she done it to get rid of her just because--because she wanted--she wanted to remove something from the stump of the old oak-tree? Oh, if Betty were that sort--if it were possible--even Sibyl Ray felt that she could not love her any longer! It was Fanny, after all, who was a noble girl. Fanny wanted to get to the bottom of things. Fanny herself could not do what an unimportant little girl like Sibyl could do. After all, there was nothing shabby in it. If it were shabby, Fanny Crawford, the last girl in the school to do wrong, would not have asked her to attend to the matter. Sibyl therefore climbed into the old apple-tree and perched amongst its branches, and gazed eagerly down on the bit of common land. She was far nearer to Betty than Betty had the least idea of. She saw her walk towards the pieces of heather, but could not, from her point of view, see what the plants were. She had really no idea that there was any special heather in the grounds; she was not interested in a stupid thing like heather. But she did see Betty go on her knees, and she did see her pull up a root of some sort or other, and she did see her take something out and look at it and put it back again. Then Betty returned very slowly across the common towards the house.