﻿94 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 72 



of the surface and some parts were heavily timbered. As indicated 

 on the accompanying map, figure 99, four mound groups stood in the 

 lowlands east of the Mississippi and a fifth was on the opposite bank, 

 land now covered by the city of St. Louis. And as is shown on the 

 map the five groups were placed with a certain degree of order to one 

 another, with the great mound. Cahokia, rising near the center of the 

 area. 



But who were the builders of the mounds, the most important 

 groups in the Mississippi Valley? The question may never be 

 definitely answered although it is more than probable they should 

 be attributed to a tribe or tribes known in historic times but who may 

 have become greatly reduced in numbers and relative importance 

 before the coming of the French. Evidently the historic Algonquian 

 tribes did not reach the eastern bank of the Mississippi until about 

 the beginning of the seventeenth century, and it is doubtful if others 

 of this linguistic family had preceded them. Siouan tribes when mov- 

 ing from the eastward may have traversed the region, but there is no 

 reason whatsoever to attribute the great mound groups which form 

 the subject of this sketch to either the Algonquian or Siouan tribes. 

 The works were probably raised by a southern tribe, a southern people 

 who at some time before the arrival of the Algonquian tribes, or 

 the migration of the Siouan tribes from the eastward, occupied the 

 region, later to move elsewhere, possibly to return southward. These 

 may have been the ancient Natchez, the Chickasaw, or some other 

 Muskhogean tribe of whom we possess no historic record : however, 

 a careful examination of the mode of construction and the contents 

 of one or more of the mounds may enable us to arrive at some con- 

 clusions regarding their origin. 



The great Cahokia Mound which rises from the level alluvial plain 

 near the center of the area, is somewhat less than 6 miles east of the 

 Mississippi and 10 miles east of south of the mouth of the Missouri. 

 It is a truncated pyramid, of rectangular form, with a broad terrace 

 extending from the south side which continues in a graded way or 

 approach. The sides of the work face the cardinal points, as do those 

 of the lesser rectangular mounds of the group. Its maximum eleva- 

 tion is about 100 feet. Its extreme length including the approach is 

 1,080 feet, and its width from east to west is 710 feet. The base 

 covers an area of approximately 16 acres. Viewed from the east, as 

 in figure 100, it appears quite regular in outline and is clearly defined 

 from base to summit. A small conical mound formerly stood on the 



