52 GEOLOGY. 



now being revealed by refined physical research. The extraordinary 

 energies displayed by radio-active substances are doubtless but an 

 initial demonstration of immeasurable energies resident in other forms 

 of matter and in the constitution of the sidereal system, and compe- 

 tent for its maintenance for unassignable periods. It does not appear, 

 therefore, in the light of recent revelations in physics, or recent dis- 

 coveries in the constitution of the stars and the stellar system, that 

 there is any sufficient reason for setting narrow limits to the life of 

 the sun. It seems more in accord with recent advances in knowledge to 

 place the compressional theory of the sun's heat in the category of 

 the earlier chemical and meteoritic theories, as true and contribu- 

 tory, but as only partial and inadequate. The one thing, perhaps, 

 above all other things, which the progress of research is bringing into 

 recognition is the immensity of the energy of the universe, of which 

 energy only a small fraction is usually apparent to us, doubtless because 

 it is chiefly in a state of equilibrium, and only becomes sensible when 

 its equilibrium is disturbed. 



There seem to be no sufficient grounds, therefore, for hesitating 

 to assume an ancestral solar system, the center of which was the parent 

 of the present sun. This involves the further quite reasonable assump- 



relative to the behavior of matter under such extraordinary conditions as obtain 

 in the interior of the sun sufficiently exhaustive to warrant the assertion that no unrecog- 

 nized sources of heat reside there? What the internal constitution of the atoms 

 may be is yet an open question. It is not improbable that they are complex organi- 

 zations, and the seats of enormous energies. Certainly, no careful chemist would 

 affirm either that the atoms are really elementary, or that there may not be locked 

 up in them energies of the first order of magnitude. No cautious chemist would 

 probably venture to assert that the component atomecules, to use a convenient phrase, 

 may not have energies of rotation, revolution, position, and be otherwise compara- 

 ble in kind and proportion to those of a planetary system. Nor would he prob- 

 ably feel prepared to affirm or deny that the extraordinary conditions which reside 

 in the center of the sun may not set free a portion of this energy. The Helmholtzian 

 theory takes no cognizance of latent and occluded energies of an atomic or ultra- 

 atomic nature. A ton of ice and a ton of water at a like distance from the center 

 of the system are accounted equivalents, though they differ notably in the total sum 

 of their energies. The familiar latent and chemical energies are, to be sure, negli- 

 gible quantities compared with the enormous resources that reside in gravitation. 

 But is it quite safe to assume that this is true of the unknown energies wrapped up 

 in the internal constitution of the atoms? Are we quite sure we have yet probed the 

 bottom of the sources of energy and are able to measure even roughly its sum total?'" — 

 On Lord Kelvin's Address on the Age of the Earth as an Abode Fitted for Life. T. C 

 Chamberlin, Science, Vol. IX, June 30, and Vol. X, July 7, 1899. 



