"All my mind was centered on my studies, which, especially at the beginning, were difficult. In fact,..." — Marie Curie

My experiments proved that the radiation of uranium compounds can be measured with precision under determined conditions and that this radiation is an atomic property of the element of uranium.

In chemical terms, radium differs little from barium; the salts of these two elements are isomorphic, while those of radium are usually less soluble than the barium salts.

We should not allow it to be believed that all scientific progress can be reduced to mechanisms, machines, gearings, even though such machinery also has its beauty. Neither do I believe that the spirit of adventure runs any risk of disappearing in our world.

During the course of my research, I had had occasion to examine not only simple compounds, salts and oxides, but also a great number of minerals.