THE SUN COOLING OFF. 415 



eyeballs, and imagination spanned another interval of 

 ages ; and I stood upon the banks of the Tigris and the 

 Nile, and the forms of Sennacherib, and Menes, and Moses 

 passed before me. As chance would have it, I returned, 

 and, passing through a cabinet where the " medals of crea- 

 tion" had been ranged in regular order, the ponderous mo- 

 lars of an extinct mammoth, dug from the soil of Michigan, 

 awakened a new thought. By its side rested the skull of 

 Oreodon, with its sheep-like teeth in a hog-like head ; and, 

 being in a mood for revery, I thought of the distant Mis- 

 souri plains where Oreodon had grazed ; and of the vast 

 lake — thrice the size of Superior — from whose water he had 

 drank, and on whose muddy banks had crawled turtles 

 that could carry oxen on their backs. And then I remem- 

 bered that thought had darted back over another stretch 

 of ages to a time when God had not yet said, "Let us make 

 man," when the wide continent was the pasture-ground of 

 elephants, and mastodons, and wild horses, and camels, and 

 sloths, and quadrupeds of strange shapes which were blot- 

 ted out of existence before ever human eye had gazed upon 

 them. 



Here, I thought, are the relics of a genuine antiquity. I 

 sauntered on, and the teeth, and vertebrae, and dimly-out- 

 lined forms of Ichthyosaurs, and Deinosaurs, and flying liz- 

 ards, and fishes clad in mail — bucklered and helmeted fishes 

 — these in succession passed before my eyes. And then 

 winged thoughts flew back through those dim ages of the 

 world's history which we call Mesozoic. I breathed a sti- 

 fling atmosphere; tepid vapors rose all around me; strange 

 foliage fringed bayous of which I had never heard ; neither 

 bird nor insect stirred the fervid atmosphere ; there were 

 no forests ; the continents were but just arising from their 

 sea-couches, and no footprint had yet been impressed upon 

 their slime-covered heads. And then I thought again of 



