128 SCIENCE AND IMMORTALITY 



Since heat causes the dissociation of elements — 

 really partial disintegration into electrons — we 

 find in the hotter stars the fewer metals, and only 

 in the cooler stars elements as numerous as in 

 our world. 



So far all is plain sailing ; but when we come to 

 try to find the relationship of the hotter and cooler 

 stars to each other, and to the nebulae from which 

 they were presumably evolved, we find many 

 difficulties and many differences of opinion. 



We may consider, with Sir Norman Lockyer, 

 that nebulae begin as clouds of cold meteoric 

 stones, which gradually gain heat as the stones 

 clash together, until they are converted into gases, 

 and then gradually cool again by radiation until 

 they are as dead as the moon. On this hypothesis, 

 which begins with cold and ends with cold, the 

 cooler stars are either newly-born or senile, and 

 the hottest stars are in the prime of life. Sir 

 Norman Lockyer claims to be able to tell by 

 spectroscopic appearances whether a metallic star 

 is beginning or ending its career. 



On the other hand, if we accept a hypothesis 

 which postulates a hot gaseous nebula, then the 

 hotter and more gaseous the star the younger it is. 



None of the hypotheses, however, so far, have 

 taken into account the electron theory of matter. 



Since the electron is the ultimate and simplest 



