One day in 1906, when Dr. Curie, his mind intent on an absorbing problem, was absent-mindedly hurrying across a wet street, he slipped and fell under a passing truck and was instantly killed. When they attempted to break the news to Madame Curie by telling her that her husband had been hurt in an accident, she looked past them with a white, set face, and repeated over and over to herself, as if trying to get her bearings in the new existence that stretched blackly before her, "Pierre is dead; Pierre is dead." Now, as on that night when she was leaving Russia for an unknown world, she saw a gleam in the blackness--there was work to be done! There was something waiting in the shadowy future for her, something that she alone could do. As on that other night, she found her lips shaping the words: "The big world has need of little me. But oh, it will be hard now to work alone!" Then her eyes fell on her two little girls (Irene was now eight years old and baby Eve was three), who were standing quietly near with big, wondering eyes fixed on their mother's strange face. "Forgive me, darlings!" she cried, gathering her children into her arms. "We must try hard to go on with the work Father loved. _Together_ is a magic word for us still, little daughters!" Everybody wondered at the courage and quiet power with which Madame Curie went out to meet her new life. She succeeded to her husband's professorship, and carried on his special lines of investigation as well as her own. The value of her work to science and to humanity may be indicated by the fact that in 1911 the Nobel prize was again awarded to her--the only time it has ever been given more than once to the same person. At home, she tried to be father as well as mother. She took the children for walks in the evening, and while she sewed on their dresses and knitted them mittens and mufflers, she told them stories of the wonderland of science. "Why do you take time to write down everything you do?" asked Eve one day, as she looked over her mother's shoulder at the neat note-book in which the world-famous scientist was summing up the work of the day. "Why does a seaman keep a log, dearie?" the mother questioned with a smile. "A laboratory is just like a ship, and I want things shipshape. Every day with me is like a voyage--a voyage of discovery." "But why do you put question marks everywhere, Mother!" persisted the child. It was true that the pages fairly bristled with interrogation points. Madame Curie laughed as if she had never noticed this before. "It is good to have an inquiring mind, child," she said. "I am like my children; I love to ask questions. And when one gets an answer,--when you really discover something,--it only leads to more questions; and so we go on from one thing to another."