A Home for Life 27 



often a restraining bridle, but the remarkable fea- 

 ture has been the general steadiness of the physico- 

 chemical environment. As we read the earth's history 

 with imagination kindled, we almost hold our breath 

 when a great period of aridity sets in, or a long suc- 

 cession of ice-ages, but in spite of local eliminations 

 the ascent of life continues. The meteorological cycle 

 is the scientific rainbow in the sky : a token of a cove- 

 nant, we say in all reverence, between the physical 

 Cosmos and Life. "While the earth remaineth, seed- 

 time and harvest, and cold and heat, and summer and 

 winter, and day and night shall not cease." Without 

 a "meteorological cycle" there might possibly have 

 been other kinds of living creatures on this earth of 

 ours, for life is defiant of circumstances as many a 

 strange habitat shows. But there could not have been 

 the advancement of life that we know, nor the climax 

 represented by man at his best. 



Our point, then, is that a multitude of "prepara- 

 tions" conspired together to make the earth a home 

 for life: the making of an atmosphere and a hydro- 

 sphere, the properties of water and carbonic acid gas 

 separately and together, the properties and abun- 

 dance of carbon, hydrogen, and oxygen in combina- 

 tion near the surface of the cooling earth, the ready 

 assumption of a colloidal state by complex carbon- 

 compounds, the characters of the porous soil, and the 

 regulative influence of the meteorological cycle. The 

 constitution of the inanimate world is in many unique 

 ways uniquely favorable to the interests of living 



