espite her shock and grief, Marie went back to work a day after the funeral. Less than a month later, the Sorbonne agreed to make her its first woman professor, taking up Pierre’s position. Meanwhile she began important lab work. Another scientist had come up with a theory that radium was not an element at all, but a compound of the known elements lead and helium. It took her several years to prove beyond doubt that radium was indeed an element.

Still more important, she decided to establish a scientific institution worthy of Pierre’s memory. Helped by her scientist friends, she persuaded the French government and the private Pasteur Foundation to fund a Radium Institute. Marie would head a radioactivity laboratory, and an eminent physician would lead its medical research laboratory.