MOUNDS IN IOWA AND ILLINOIS. 359 



that the foot-prints were carved, and Dr. D. D. Owen was of the same 

 opinion. 



Maiitell, in the first edition of his Wonders of Geology, vol. i, p. GG, 

 copies the account and figure from Schoolcraft, hut he falls into the 

 erroneous opinion that they were actual impressions of feet. 



MOUNDS IN MUSCATINE COUNTY, IOWA, AND ROCK ISLAND COUNTY, ILLINOIS. 



By Tiieron Thompson, of Muscatine, Ioiva. . 



Along the bluffs of the Mississippi River, near Muscatine, Iowa, for a 

 distance of 10 miles, is a series of mounds and earthworks. Opposite 

 this point, in Illinois, is a similar series of mounds running down the 

 river for a distance of 20 miles. The mounds on the Iowa side are all in 

 Muscatine County ; those opposite are iu Rock Island County, Illinois. 



The mounds are now surrounded by a growth of young timber, prin- 

 cipally oak, which shows no evidence of an older growth before it. 

 The localities were no doubt prairie lands before, or when the mounds 

 were constructed. The laud is all tillable, except the more precipitous 

 bluffs. The river runs east and west at this place, and the mounds are 

 generally upon the most commanding positions. There are, however, 

 some remains of mounds upon a large island known as Muscatine Island. 

 They have been very much reduced by cultivation. The river below 

 Muscatine formerly followed the Iowa bluffs in the shape of an elbow 

 for a distance of 20 miles ; but at some remote period it cut a new chan- 

 nel across this elbow, making, as it were, an island, low, flat, and sandy, 

 about 20 miles long by 8 miles wide. The old channel along the bluff 

 remains deep and full of water. It is around these bluffs, which for- 

 merly bordered the river, and upon this island that the mounds are sit- 

 uated. Those on the island are on the river side overlooking the river, 

 and were evidently built after the river changed to its present course, 

 which may serve as a clue to the age of the mounds. In some places 

 gullies have washed back into and past the mounds, and, upon Musca- 

 tine Island, the river has encroached so far as to frequently wash out 

 pieces of pottery, &c. The mounds are in size from 3 feet to 30 feet in 

 diameter and 6 inches to 5 feet in height. They are generally in groups 

 and covered with timber. Nine out of ten are round, the others re- 

 sembling remains of earthworks from 6 to 20 feet in* length and 5 feet 

 wide, placed end to end, with a gap of 5 feet between. There are quite 

 a number of them in group No. 1. They are composed of the same ma- 

 terial as the surrounding surface, which is clay and sand on the bluffs, 

 and on the island sand and gravel. In exploring the mounds we some- 

 times find in the center some evidence of fire, bits of charcoal, &c. In 

 none of those that I have thus far examined is there evidence of layers 

 of other earth than that of which the mounds are composed. There is 



