2o8 PHYSICAL BASIS OF CIVILIZATION 



combinations could be formed, the conditions 

 existing in that part of the earth where the periph- 

 ery of the denser interior globe adjoins the lower 

 surface of the atmospheric envelope must have 

 included all the prerequisites for the original for- 

 mation of these compounds out of their elementary 

 constituents. Science, so far, has not ascertained 

 what these prerequisites were. 



This is not at all surprising, for ever since hu- 

 manity has existed, and long aeons before science 

 was born, living organisms have always been present 

 as active factors in the process of the formation 

 of protoplasmic compounds. Although, therefore, 

 these prerequisites cannot be exactly stated, it is 

 yet well known that temperature, atmospheric 

 pressure, and the influence which these two exercise 

 over the kinetic activity of so-called chemical affin- 

 ities, were among the most essential. 



Since even in its higher forms, which are enabled 

 by their organization to resist environing influences, 

 life cannot continue at temperatures or atmospheric 

 pressures either much higher or much lower than 

 those ordinarily prevailing in the present era between 

 the equator and the polar circles — since the cooling 

 of the earth, which is still going on, must have been 

 continuous ever since our planet ceased to be a 

 fiery liquid globe with a vaporous envelope ; there- 

 fore it may be stated with entire confidence, that 

 before the formation of any protoplasmic compounds 

 whatsoever, the crust of the earth had cooled to 





