CHAPTER II 

 THE ENVIRONMENT 



A 



ASTRONOMY 



N examination of the relationship be- 

 tween m^ej^lSiHjen^irijnme nt r in w hich 

 by riteans of the simplifying postulates pre- 

 Tiomly~!TrvHnpr rl life i n nrhi Tr aTify Lak e n as- 

 an invariant T sh ould, if it is to be quite g eneral. 

 rest upon a physico-chemical description of 

 the whole universe. We require to know the" 

 form and structure of stars and of interstellar 

 space, of nebulae and of solar systems, and 

 the conditions and changes which accompany 

 such aggregations of matter. Evidently this 

 requirement can be but imperfectly fulfilled, 

 and yet one need not be too apologetic in 

 venturing the attempt. In the end, to be 

 sure, we shall found our argument upon the 

 safe basis of terrestrial phenomena, but mean- 

 time it will be an advantage to consider con- 

 ditions far and wide. 



38 



