14:2 ORIGIX OF THE E A II Til . 



above and below each other in the same system of rocks, the 

 two are never found upon the same laminar as though the 

 birds, during the frosty season, were entirely absent, having 

 migrated to a warmer climate, to return again with the return 

 of summer. 



On the same strata are also sometimes found impressions 

 which could only have been made by the pattering of rain- 

 drops during the passage of a small shower-cloud ; and the 

 forms of these sometimes even infallibly indicate the course 

 in which the wind was blowing at the time ! 



Here, then, is the earliest distinct indication of the preva- 

 lence of atmospheric conditions somewhat similar ito tliose 

 which now obtain upon the earth's surface. We find, here, 

 unmistakable evidences of summer and winter, warm and cold 

 latitudes, rain, winds, clouds, and sunshine conditions which 

 clearly could not have existed to any great extent, during any 

 previous period. 



Concerning the relics of the olden time, from which these 

 atmospheric and terrestrial conditions are inferred, Professor 

 Hitchcock (to whom the scientific world is much indebted for 

 bringing them to light) remarks : " It is a most interesting 

 thought, that while millions of men, who have striven hard to 

 transmit some trace of their existence to future generations, 

 have sunk into utter oblivion, the simple footsteps of animals 

 that existed thousands, nay, tens of thousands, of years ago, 

 should remain as fresh and distinct as if yesterday impressed, 

 even though nearly every other vestige of their existence has 

 vanished. Nay, still more strange is it, that even the patter- 

 ing of a shower at that distant period, should have left marks 

 equally distinct, and registered with infallible certainty the 

 direction of the wind."* 



* Hitchcock's Geology, p. 155. 



