THE LAPSE OF TIME. 121 



entirely of animal remains, such as those of shells and 

 fish, not only are we forced to admit a long period for 

 the successive generations of those creatures, but we are 

 forced to observe the products of the ocean lying 

 actually above the products of the dry land, as though, 

 according to the old poetical extravagance, the stag and 

 doe had taken to the waters and the fishes been building 

 in the tree-tops. The conclusion is inevitable, that what 

 was once dry land, fruitful in vegetation, in process of 

 time became a swamp, and from the swamp became a 

 sea. It will be a fresh surprise, but a fresh evidence 

 of time's duration, if above the limestone we find more 

 clay with more plants buried in more mud, and over- 

 topped by more limestone. Bearing in mind the old 

 supposition, that order and beauty and life upon the 

 globe are only six thousand years' old, astonishment 

 should reach its climax when we find, as we do, that 

 within the thickness of only a few feet of the earth's 

 crust, the record that we have been describing is re- 

 peated again and again and again ; but beyond the 

 climax, a fresh and overpowering marvel awaits us, 

 when, as at one spot in British America, the record 

 expands itself from a few feet into sixteen thousand, 

 showing conclusively by eighty successive bands of coal 

 that fourscore times at least, and perhaps many more, 

 while that thickness of the earth's crust was forming, 

 the waters gave place to dry land, and in turn the dry 

 land to the waters, showing conclusively that during 

 all the period of these changes tall forests of graceful 

 trees abounded on the globe, along with exquisite ferns 



