64 WHAT IS LIFE 



condition with continents formed, or with a sohd 

 crust, without immediately thereafter further pos- 

 tulating the beginning of reduction, or disintegration, 

 of the continental surfaces. This reduction un- 

 doubtedly proceeded in varying degrees and at vary- 

 ing rates, depending upon the sum total of pre- 

 vailing local conditions. At this early stage, tem- 

 perature was a prominent factor. But the immediate 

 and intimate factors in disintegration were the sur- 

 face relations of continent, water — ocean — incipient 

 ocean probably, and inland waters, and atmosphere. 

 These provided at that early time all the various 

 physical surface contacts known; namely: 



solid — solid; solid — liquid; 



liquid — liquid; solid — gas; 



gas — gas; liquid — gas. 



That disintegration necessarily had to set in is 

 beyond a doubt. And, inevitably, in the course of 

 time colloids, as well as other solutions, had to form. 

 On the importance of colloids in geologic history 

 light is thrown by Raphael Ed. Liesegang, in his 

 volume Geologische Diffusionen. 



Concerning the formation of colloids on the life- 

 less earth we have, then, two fundamental prop- 

 ositions; namely: (1) we are bound to assume that 

 the formation of colloids, as of other solutions, was 

 inevitable; (2) a definite grouping of elements does 



