The mutability of the elements by Ramsay is most wonderful. He has found that the radium emanation develops into helium, and when the same emanation is passed through water it changes into neon. If it is passed through a solution of a salt of copper, it resolves itself into argon; and when copper is acted upon by the radium emanation it is converted into lithium! Argon, helium, radium, neon, krypton, and xenon are non-valent elements, and as such have not the power of combining with other elements. Thus they appear to be the wreck of the material universe, which seems to be undergoing universal dissolution. In the course of a thousand million years one cannot say what the gold and silver, the copper and lead, and much else of the solid structure of this globe may have become. Another marvellous feature is the unheard-of energies which these fragments of radium set free in their break up. The powers of Nature in this respect astonish us as much as its extent in space and time.
Whether Lord Kelvin could read the future or not as to the drift of modern investigations on electrons and emanation "it would be shallow to believe that such men as Kelvin, with faculty quickened and outlook widened in the high air to which their fame raises them, really discerned no more than we, who have only their written words for authority, can perceive that they discerned. Great position often invests men with a second sight,
