The interpretation of radium : being the substance of six free popular experimental lectures delivered at the University of Glasgow, 1908 / by Frederick Soddy ; with illustrations.

  • Soddy, Frederick, 1877-1956.
Date:
1909
Catalogue details

Licence: In copyright

Credit: The interpretation of radium : being the substance of six free popular experimental lectures delivered at the University of Glasgow, 1908 / by Frederick Soddy ; with illustrations. Source: Wellcome Collection.

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    Certainly no shells ever constructed would answer this requirement. Truly, in the words of Sir John Herschel, the atom bears the essential character of a manufactured article, but of a degree of per- fection humanly unattainable. But with regard to the process of manufacture and of the cause of this undeviating fidelity to a few types, what a revolution of thought has taken place in the last few years ! The evolution, or rather devolution, of matter, its continuous change, the generation and destruction of atoms—all of the things which seemed impossible in Clerk Max- well’s day—we know to be going on before our eyes. It is true the processes call for periods of time so vast, even in the most favourable cases, that the physicist of a generation ago would have dismissed them as physically inconceivable. Yet these periods are to-day actually determined by direct measurement in the laboratory. Instead of regarding the hundred or less ele- o o ments which exist to-day as manufactured, created, once for all time, we rather regard them as existing because they have survived. All other forms less stable than those we recognise as elements have been weeded out. Over sufficiently great periods of time the rarity or abundance of an element must be controlled by its degree of