QUAiSTTITY AND ACTION OF AVATER 19? 



ments ; while the ground water is effective in solution, ionization, aqueo- 

 igneous fusion, and probably most of the chemical changes in the earth 

 crust, including all those interrelated with vital action. The aqueous vapor 

 mixed with the air regulates or at least conditions all the earth-making 

 processes dependent on temperature — indeed, could that portion be re- 

 moved without disturbing the rest, the earth would probably be deadened, 

 something like the moon, so as to inhibit life and render ineffective most 

 of the molecular and molar movements of surface and crust. Under 

 special conditions of temperature (itself conditioned by the liquid and 

 gaseous H20),.the solid phase of the hydrosphere is an effective mechan- 

 ical agency, gathering in glaciers, grinding rocks, accumulating deposits, 

 and shaping earth forms; chemically, it is inert. The stream water 

 works incessantly, both mechanically and chemically; it has shaped some 

 nine-tenths of the land surface of the glol^e; it has planed down moun- 

 tains, leveled continents, transported over and over again a great part of 

 the rock matter of the earth crust, and through transfer of load played 

 a part in epeirogenic movements by which the continents have been ex- 

 tended; and in connection with the rainfall by which it is maintained, it 

 has throughout the ages conditioned vital development and all secondary 

 processes, from the accumulation of soil to the evolution of human 

 activity. Without this smallest but most energetic division of the hydro- 

 sphere by which the face of the earth has been wrought into form and 

 fruitfulness, the planetary surface would be a chaos. 



OENEBAL FUNCTIONS OF THE HYDROSPHERE ■ 



Viewed in each of its principal divisions and in some leading aspects, 

 the material of the hydrosphere is homologous with the typical substances 

 of the lithosphere : It yields to gravity and both interacts mechanically 

 and reacts chemically with other terrestrial substances, so that it conforms 

 like other inorganic bodies to the laws of statics and dynamics, and may I 



be treated in equilibrium under hydrostatics and in motion \mder hydro- J 



dynamics ; yet viewed as a whole the hydrosphere takes on a significant, fl 



or at least suggestive, character which may be likened to the automacy 

 (automaticity of earlier lexicographers) of the organic world and the 

 autonomy of the human world — it assumes a semblance of self-activity 

 in its changes of state and movements in space which tends to facilitate 

 its own working and perpetuate its own efficiency as a planet-shaping 

 agency, for example, in that its presence is necessary to the temperature 

 of the planet which in turn regulates its changes and movements. In 

 tills general view the terrestrial HjO in some measure bridges the break 



