George's blind sister was slender, brown-haired. Her face had a gentle, wistful beauty, enhanced into pathos by the blankness of her pale-brown eyes. Here in her own home where she had lived all her sightless life, she could move with almost normal freedom. It was she who took care of Lea at first. But as the days passed into weeks the strange little visitor, alert of mentality, always with a whimsical smile, began taking care of the blind girl. Lea's language of soft, weird syllables defied Professor Carter's classification. He and George could do nothing with it. But from the first, with extraordinary concentration and abnormal aptitude, at once Lea began learning English. That her mentality was different, and in this respect certainly far superior to their own, immediately became apparent. With amazing rapidity she memorized and understood the words and phrases with which patiently they drilled her. With Alice as her constant companion, she made an immediate effort to fit into what was for her, the strangeness of their household. Often she would laugh with what obviously was a keen sense of whimsical humor--a little rippling rill of girlish laughter.... The knowledge of who she was and where she had come from, of necessity was imparted gradually to the still incredulous Carters. Obviously now she was struggling with their language with the desire to tell them. There was still another mystery about her which that very first evening, Alice had discovered. Beneath one of her armpits, held by a strap around her body, there was a small vial, seemingly of some tough vegetable fiber. She had wildly, vehemently resisted everyone's effort to touch it; she would never let it leave her person. Then at last came her ability to make them really understand that she had come from a strange world of infinite smallness. A world so tiny that it was vastly beyond the reach of any microscope. A world in an atom. "I watch--very careful as I grow large," she said. "I can show you now from where I come." Then she led them, amazed and, of course, still incredulous, out into the garden. At the broken old sundial she indicated to them its metal pointer, near the end of which there was a tiny abrasion. "From there," she insisted. "I notice it well when I come. You wait--I tell to you soon--when the English for me get better." To young Carter who watched her always with a mixture of struggling emotions which he could not himself understand, it seemed that a shadow crossed her expressive little face as she showed them the spot on the green-bronzed aged pointer of the old sundial. A single atom, down there in the metal, housed her world. She was worried about her people....