The Nobel Prize in Chemistry 1908 was awarded to Ernest Rutherford "for his investigations into the disintegration of the elements, and the chemistry of radioactive substances".
 

His investigation of the radiating phenomena that characterize the element thorium led Rutherford to make the remarkable discovery that that element emanates a gaseous substance, the so-called thorium emanation, which has since been shown to be of elemental nature, and with the agency of liquid air has proved capable of being condensed into fluid form.
 

As will be seen, Rutherford's discoveries led to the highly surprising conclusion, that a chemical element, in conflict with every theory hitherto advanced, is capable of being transformed into other elements, and thus in a certain way it may be said that the progress of investigation is bringing us back once more to the transmutation theory propounded and upheld by the alchemists of old.