THROUGH THE GEOLOGIST'S EYES 



Then, after a vast interval, there comes a break: 

 something hke an end and a new beginning, as if one 

 day of creation were finished and a new one begun. 

 The different formations he unconformably upon 

 each other, which means revolution of some sort. 

 There has been a strike or a riot in the great mill, 

 or it has lain idle for a long period, and when it has 

 resumed, a different product is the result. Some- 

 thing happened between each two layers. What? 



Though in remote geological ages the earth- 

 building and earth-shaping forces were undoubtedly 

 more active than they are now, and periods of de- 

 formation and upheaval were more frequent, yet 

 had we lived in any of those periods we should prob- 

 ably have found the course of nature, certainly when 

 measured by human generations, as even and tran- 

 quil as we find it to-day. The great movements are 

 so slow and gentle, for the most part, that we should 

 not have been aware of them had we been on the 

 spot. Once in a million or a half -million years there 

 may have been terrific earthquakes and volcanic 

 eruptions, such as seem to have taken place in Ter- 

 tiary time, and at the end of the Palaeozoic period. 

 Yet the vast stretches of time between were evi- 

 dently times of tranquillity. 



It is probable that the great glacial winter of 

 Pleistocene times came on as gradually as our own 

 winter, or through a long period of slowly falling 

 temperature, and as it seems to have been many 



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