ABSTRACT
Marie Sklodowska-Curie, 1867–1934, is one of the most well-known figures in the history of science, being the first to win a Nobel Prize twice, for the development of the theory of radioactivity and for the discovery of polonium and radium, respectively. She was also the first woman to win the prize. This chapter reflects on the limits of what can be seen or perceived, and the need to contrive methods to make knowledge out of the invisible. The discovery of the phenomena of radioactivity adds a new group to the great number of invisible radiations now known, and once more we are forced to recognize how limited is our direct perception of the world which surrounds us, and how numerous and varied may be the phenomena which we pass without a suspicion of their existence until the day when a fortunate hazard reveals them.
