CREATION BY EVOLUTION
revolve a few or many planetary electrons in one, two or several shells, each capable of housing a definite number. Only the electrons in the outermost shell determine the chemical characteristics of the various atoms of the elements.
Some of the most complex atoms, such as those of uranium, thorium, and radium, are radioactive; that is, there is a sort of unrest in the nucleus which operates to break down the equilibrium existing among the protons and electrons and results in the shooting off, at tremendous velocity, of electrons and of groups of protons and electrons from the nucleus. The so-called Alpha rays given off by radioactive substances are composed of particles identical with the stripped nuclei of the helium atom, one of the lightest and simplest atoms. The emission of these rays is nothing more or less than a process of evolution of elements, one element becoming transformed into another. By radioactive disintegration the most complex elements, such as uranium, thorium, and radium, are reduced slowly and by distinct steps to elements of less complexity and greater stability. Thus when an atom of radium loses one Alpha particle it is reduced to radon, an extremely inert gaseous element. Radon goes over by another step into polonium and lead, and radioactive lead, by a further change involving the capture of another electron, becomes the element bismuth.
Physicists are just at the beginning of their program of transforming the elements or atoms into one another, and doubtless their future research will disclose many startling transformation. The evidence so far available points to the conclusion that what we once considered the most fixed, the most immutable units of the universe are far from stable—they are undergoing orderly transmutation from more complex to simpler forms. The transmutation seems very slow to us, but expressed in terms of cosmic time it is really rapid.
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