"Oh, that's all right, mamma. I make full allowance for Belle. She's a little crude yet, but she'll improve in time." Belle gave a scream of joy. Her sense of the ridiculous, always extremely keen, made her delight in her little sister and the perfectly placid way in which she sailed through existence with the lofty superiority of her type--a type that is the peculiar result of supercivilization and the deferential treatment of fashionable schoolmistresses who bow to wealth as before a god. "Run in and say good-night to father. He won't mind being disturbed for a moment by you." "I don't think I will," said Ethel. "The sight of his laboratory may give me a nightmare. I really must be careful about myself just now. Good night, mamma dear. Don't sit up too late. Good night, Belle. I should advise you to go to bed at once. Your complexion is beginning to show the effects of late hours already." "Oh, you funny little thing," said Belle. "You give me a pain. Trot off to bed; and instead of reading Wells, Ibsen and George Bernard Shaw, try a course of Louisa Alcott and a dose of Swiss Family Robinson. That'll do you much more good and make you a little more human." But even this plain sisterly speaking had no apparent effect. Ethel gave Betty, who had been watching and listening to the little bout with the surprise of an only child, a small peck on the cheek. "Good night, dear Betty," she said. "I'm glad that you're going to be my sister-in-law. Unless Peter has changed very much since he's been away he'll make a good husband." And then, with quiet grace, she left the room. No one, not even Belle, whose high spirits and love of life had led her into many perfectly harmless adventures when she was the same age, suspected that Ethel was up to anything. They were wrong. The self-constituted invalid had invented anæmia for two very good reasons. First, because she was not going to be deprived of welcoming her big brother when he returned home for good, school or no school, and second because she had struck up a surreptitious acquaintance with the good-looking boy next door. At present it had gone no further than the daily exchange of letters and telephone calls. The adventure was in the course, however, of speedy development. The boy was going to pay her a visit that evening, by way of the roof. No wonder Ethel didn't want to be disturbed. With an unwonted burst of extravagance Betty took a taxi home as soon after dinner as she could get away. "Is there a letter for me? Is there a letter for me?" she asked the moon and all the stars in the clear sky as her rackety cab bowled swiftly downtown. She let herself in and the first thing that caught her eyes was the welcome sight of a thick envelope addressed in Peter's big round, honest, unaffected hand. "Peter, oh, my Peter!" she whispered, pressing the letter to her lips.