142 Association of American Geologists and Naturalists. 



was formed since the period of their construction. Trees growing 

 upon the works shew that their origin must date back a long period. 

 The forests that cover these works are in no way distinguishable 

 from the other forests. The same varieties of trees are found, in 

 the same proportions ; and they have a like primitive aspect. This 

 fact was observed by the late President Harrison, and he considered 

 it one of the strongest evidences in support of the great antiquity of 

 of these works. And here an extract was read from an address 

 made by him before the Historical Society of Ohio. 



Within the mounds are found implements, ornaments, sculptures, 

 6:0., &c., composed of materials generally foreign to the region in 

 which they are discovered, and often exceedingly rai"e and beautiful. 

 The identification of the localities from which these were obtained 

 must tend to reflect light upon the origin, migrations, and inter- 

 course of the race of the mounds. Obsidian, a volcanic pi'oduct, is 

 found in the mounds on the alluvia of the Ohio. The nearest 

 place where it is known to exist in abundance is Central Mexico, 

 the ancient inhabitants of which country applied it to the very pur- 

 poses for which it was used by the race of the mounds. 



In these mounds are discovered native silver and copper from the 

 shores of Lake Superior, pearls and shells from the Southern Gulf, 

 obsidian probably from the volcanic ridges of Mexico, mica from the 

 primitive ranges of the Atlantic coast, galena from the upper, and 

 fossil teeth from the tei'tiary deposites of the lower Mississippi, be- 

 sides numberless other remains. 



Sil^'er and copper are the only metals which have been developed 

 from the depositions. The ore of lead is quite abundant, and lead, 

 under circumstances, implying a knowledge of its use on the part of 

 the ancient people. No iron, or traces of iron, has been discovei'ed, 

 except in the late deposites, and it is certain that the ancient people 

 were wholly unacquainted with its use. 



A mass of native copper weighing twenty-three pounds, from 

 which pieces had evidently been cut, was discovered a few years 

 since in the vicinity of Chillicothe, Ohio. It is nearly certain that 

 both silver and copper were obtained in a native state, and both 

 metals appear to have been wrought in a cold state. They were 

 undoubtedly obtained from the shores of Lake Superior. The 

 copper was frequently wrought into axes, and various other imple- 

 ments, and into ornaments, beads, bracelets, &c. (Several speci- 

 mens were exhibited aisplaying a considerable degree of skill in the 

 workmanship.) 



The implements and ornaments discovered in the mounds are more 

 o-enerally made of stone ; and they wrought the rarest minerals with 

 great skill. Their lance, and armed heads, and cutting implements, 

 were o-enerally made of quartz, and some of them from the pure 

 limpid crystals of this mineral, and some from obsidian. From one 

 altar were taken several bushels of finely wrought spear-heads of 



