NUCLEUS AS SOURCE OF ENERGY 167 



would be the same as to account for the 

 formation of the elements. These may have been 

 constituents like the other elements of the nebula 

 of which the planet once consisted ; or they may 

 have been carried to our planet by meteors, as 

 Lord Kelvin and von Helmholtz imagined that life 

 originally appeared amongst us. 



In our hypothesis, however, we do not suppose 

 that ordinary germs appeared thus ; for the high 

 temperature to which they must have been sub- 

 jected, at some time during their history before 

 reaching the surface of the earth, would have been 

 sufficient to destroy them. What we suppose to 

 have been sufficiently permanent and stable was the 

 ultimate nucleus ; which might have been formed 

 at, or at any rate which might have resisted, 

 the high temperature through which it should 

 at one time have had to pass ; whilst the forma- 

 tion of cellular life as we see it to-day was the 

 result of the subsequent interaction of this radio- 

 or bio-element with organic compounds in such a 

 manner as has been suggested. Eeasoning, then, 

 by analogy from the behaviour of the artificial 

 cells, it was in this way, we think, that the most 

 efficient types of cells were formed, and in virtue 

 of their efficiency some of them have been able to 

 survive. 



Professor Pfluger, of Bonn, regarded cyanogen 

 as the substance which thus gave rise to the 

 formation of proteids. Cyanogen does resemble in 

 physical structure the hypothetical substances which 



