Читать книгу Modern cosmogonies онлайн

28 страница из 31

But here a caveat has been entered by the latest inquirers—a caveat not to be ignored, though based upon modes of action still exceedingly obscure. Radio-activity is a fledgling science; its capabilities, though immense, are vaguely outlined. Until they more fully approve themselves, it would be unwise to admit conclusions which they may eventually enforce. Subversive ideas are in the air; the theory of atomic dissociation goes to the very root of things, and it insistently claims assent. Its verification, by disclosing the presence in the universe of a measureless store of unsuspected energy, would overthrow all the calculations of cosmic time heretofore attempted, and might protract indefinitely the radiative span of the sun.

Mr. W. E. Wilson pointed out in 1903ssss1 that its entire thermal output could be supplied by the spontaneous liberation of energy from 3·6 grammes of radium in each cubic metre of its volume; and although we have no evidence of the actual existence of radium in the sun, the possibility that chromospheric helium represents the decay of solar radio-active elementsssss1 must be taken into consideration. The ground here is undermined with pitfalls. We can only see that although Helmholtz's gravitational rationale of the sun's long life-history remains true, the results derived from it may be profoundly modified by co-ordinate processes, variously efficacious according to circumstances, perhaps knowable, but as yet unknown.