Association of American Geologists and Naturalists. 153 



The void, from which the earth was taken, remains to this day, 

 and is as evidently an artificial excavation, to form an artificial 

 hill, as any modern fortification with its ditch and glacis. There 

 remains not the smallest doubt, that these mounds were erected 

 both as sepulchres, for distinguished individuals, and as monu- 

 ments of victories. The remains of the dead have been often 

 found in them, either skeletons or ashes — with heads of spears, 

 swords, bones of horses, dogs and other domestic animals, some- 

 times beads, trinkets, and female ornaments, articles dear to the 

 departed while living and which were believed to be important 

 to them in another world. 



Prof. H. D. Rogers remarked in relation to Mr. Lyell's opin- 

 ion of the gradual rising of the North American terraces, that if 

 such was the case, fossil shells or marine sedimentary accumula- 

 tions, should be found at all elevations on the mountain slopes, 

 which are covered with marks of diluvial action, at every height. 

 It has not been shown by examination that such is the case, 

 hence he infers that the cause which produced the elevation was 

 paroxysmal in its operation and effects, and not secular, or grad- 

 ual, and uninterrupted. In order to explain the theory of diluvi- 

 al phenomena, he would suppose with Mr. Lyell, and others, that 

 the region around the north pole was capped with ice, in immense 

 masses, and that by a sudden outburst of volcanic action, this was 

 dispersed, and sent in a quaquaversal direction towards the equa- 

 tor. But if we suppose that this was accompanied by an earth- 

 quake, rocking, or wave-like motion, of the bed of the ocean, the 

 whole mass of torn-up strata would be shoved violently from N. 

 to S., and at every heaving of the earth, a mass of water would 

 be thrown forward, like the rolling in of a tremendous surf Mr. 

 Couthouy's observations among the coral islands, would go to 

 strengthen this theory, while the rocking movement of the earth's 

 surface during an earthquake, had been long ago admitted. 



Mr. Couthouy remarked in relation to the paroxysmal rise of 

 the land at intervals, that on one island which he bad visited, 

 which was about two hundred feet in elevation ; about one half 

 way from the base to the summit, the face of the cliff was deep- 

 ly sea- worn and indented ; as its present base would appear should 

 it be at this moment raised above the ocean level, when it would 

 present similar marks of powerful and long continued action of 

 water, at the part which was before on a line with the sea. In 



Vol. xLiii, No. 1.— April- June, 1842. 20 



