It struck Wendell as strange that, whatever adventures the Wishing Stone had thus far brought him, seemed to increase the number of things he had to wish for. He had never yearned for an aeroplane before, but now it seemed to him that he couldn’t bear to part with this one to the Pixie. Of course, he had often thought he would like a dog; but now that the Wishing Stone had brought to life this wagging, barking, loving morsel of a pup, Wendell was almost unhappy without him. He wondered if it would be that way all the time,--if every granted wish would produce more ungranted ones. If that were so, it would really be happier not to begin the endless chain, not to have the first wish granted. That was the way it turned out in a good many of the fairy stories,--the black pudding, for instance, on the end of the old woman’s nose. A great truth was almost within Wendell’s grasp for the moment,--that it is not the attainment of a wish, but the effort to attain it that brings us happiness: that right activity, not idle possession, is man’s happiest endowment. Wendell had his finger on this key to happiness, but as he was only a small boy flying a toy aeroplane, and not a great philosopher, he did not grasp the key, but let his thoughts wander to the Pixie, who would probably be all ready with another task after dinner. When the Pixie suddenly appeared that evening (sitting this time on top of the chiffonier, with his thin long legs drooping over the drawers), Wendell said triumphantly, “Well, I got the aeroplane.” He stroked it lovingly where it stood balanced on his desk. “Why, yes, it’s an aeroplane, all right,” granted the Pixie; “but it isn’t traveling underground.” “But it was when I found it,” protested Wendell. “A boy had it in the Subway.” The Pixie looked crestfallen. “I never thought of that,” he admitted. “You win.” “Tell me all about it,” he added with some curiosity. Wendell told him the whole thing, but the Pixie looked grave when he mentioned the Wishing Stone. “You’re not using them up too fast, are you?” he said doubtfully. “That makes two, you know.” “Two what?” said Wendell. “Why, two wishes. You only have three, you know.” “Is that a fact?” asked Wendell anxiously. “I didn’t know. Is that straight?” “Of course,” said the Pixie. “Everything goes by threes in fairy stories.” “I’m afraid you’re right,” said Wendell gloomily. “I know I am,” said the Pixie. “Well, are you ready for the next task?” “All right. What comes next?” asked Wendell. CHAPTER IV WENDELL FINDS AN UNEXPECTED ALLY The Pixie brightened a bit. “I have a poser this time,” he said. “You must find an acorn on Acorn Street.” It was Wendell’s turn to look crestfallen. As every Beacon Hill boy knows, Acorn Street is only one block long, or rather one block short, and there isn’t an oak on it. In fact, there isn’t a tree of any kind: there isn’t room for one.