64 THE TWO ATMOSPHERES 



portant that one is justified to designate the primeval atmosphere as 

 pre-actualistic, in contrast to the present, actualistic one. 



I reahse this is an equivocal step. Even in the primeval atmos- 

 phere, natural processes followed the same laws of nature as they do 

 now. So there is, if you like, still uniformitarianism. Uniformitarian- 

 ism even forms the base for all biochemical theory referred to in the 

 preceding chapter. Chemical bonds in the 'thin soup' are postulated 

 as having been exactly the same as chemical bonds between the same 

 compounds found now, either in organisms, or produced in the 

 laboratory. 



However, even if there was this basic sort of uniformitarianism, or 

 let us say, even if there was a uniformity of processes on the physico- 

 chemical level, the result is different. The result of these selfsame 

 processes then and now was often exactly opposite. This difference 

 follows, let it be stated again, from the complete antithesis between 

 the primeval anoxygenic atmosphere and the present oxygenic one. 



To pin down this distinction, a distinction which is not essential 

 in its underlying primary physico-chemical processes, but which is so 

 very fundamental in its ultimate result as revealed in the environ- 

 ment eventually created on the surface of the earth, one is justified, 

 in my opinion, to speak of the difference between primeval and 

 present atmosphere as pre-actualistic opposed to actualistic, 



EXOGENIC AND ENDOGENIC PROCESSES 



This distinction between the pre-actualistic anoxygenic atmosphere 

 and the actualistic oxygenic, of course, also affected the lifeless sur- 

 face of the earth, the upper layers of the hydrosphere and the litho- 

 sphere; that is, all contemporary land surfaces and bodies of water 

 which stand in close contact with the atmosphere. 



In geology, processes which take place on the surface of the land, 

 on the so-called lithosphere, or in water, in the hydrosphere, together 

 are grouped as the exogenic processes. They only affect the outer 

 skin of the earth, and in turn, they are very much affected by the 

 atmosphere. The group of exogenic processes is different from those 

 processes occurring within the crust of the earth, which together are 

 called the endogenic processes. Typical endogenic processes are, for 

 instance, mountain-building, metamorphosis of rocks at depth, or the 

 formation of granites, and even, although its products reach the sur- 



