CHAPTER II. 



THE AGE OF ICE-WATER — GRADUAL DISAPPEARANCE OF WATER — EARTH 

 MAKES STEAM — A WITNESS OR TWO. 



Stated by the best obtainable evidence, this zone of ours has 

 passed through at least one — possibly several — -glacial epochs. 

 We have now to consider only the last, the tffects of which are 

 still to be seen about us on every hand, when sought for with 

 asking eyes. 



The glr.cial and inter-glacial theories, as now understood and 

 generally accepted, offer a wonderfully inviting field for study. 

 No time will be lost in any discussion of the causes which made 

 necessary an age of ice, and we shall now simply illustrate our 

 history with some [pictures showing the action of water, notably 

 of streams proceeding from rapidly melting ice-fields. 



We are tempted to record much matter not wholly within the 

 scope of our story ; we find it difficult to avoid asking and even 

 attempting some answer to questions which troop about and 

 beset us at every turn, but must be content with a few prelim- 

 inary generalizations. 



We may conceive Earth in its desolation, its first-born naked- 

 ness, before desire arcjse, absolutely without life other than that 

 which may have been potential. We then reach a later period in 

 whicli there was indeed life, existing in low forms, mair.tained 

 with difficulty, intermittent and migratory. Still later we recog- 

 nize a true life-bearing age, in which plants and animals inclus- 

 ive of man appeared, moved and died. 



To the foregoing it seems necessary to add that as there were 

 life-bearing and non-life-bearing periods so there were non-life- 

 producing as well as life yielding zones. Moreover, that climatic 

 changes in the same zone rendered it now fit now unfit for life, 

 and this entirely without reference to elevation and subsidence 



