NO. 15 SMITHSONIAN EXPLORATIONS, I92I 97 



South of the lake, away from the main group, is a single, isolated 

 mound. Others may have stood within the area, all traces of which 

 have disappeared. 



CENTRAL OR CAHOKIA GROUP 



Surrounding the great Cahokia Mound, which has already been 

 briefly described, were many lesser works, about seventy in number, 

 some of which were more than 40 feet in height. Some were rec- 

 tangular, others were circular and although at first glance they appear 

 to have been placed without definite order, nevertheless it is quite 

 evident that in several instances they were so arranged as to create 

 inclosed areas, thus conforming with the position of the mounds of 

 the three lesser groups to the north, west, and south of the central 

 cluster. 



Unfortunately the large majority of the mounds east and west of the 

 great central structure have been much reduced and modified by the 

 plow, while several have been practically destroyed and a slight rise is 

 all that remains to indicate their position. The inclosure formed of 

 the smaller mounds on the east is clearly defined and gives the impres- 

 sion of having been intentionally planned and arranged, but for what 

 purpose may never be determined. And although many of the lesser 

 mounds have thus lost their original form and appearance, Cahokia 

 remains the most important and impressive native work in the Valley 

 of the Mississippi. As the great mound now stands it should be pre- 

 served : to permit its destruction would be a calamity, an irrepar- 

 able loss to future generations. 



The rectangular work immediately southwest of Cahokia was 

 occupied from 1810 until 1813 by a small body of Trappist monks, 

 during which time their garden was on the southern terrace of the 

 great mound. According to the survey of 1875- 1876 from which all 

 measurements now given are derived, this lesser mound was 25 feet 

 in height, its base line from north to south was 180 feet and from 

 east to west 200 feet. Just south of this is a small circular work. A 

 short distance east of south of the latter stands a conical mound which 

 rises 44 feet above the plain, having a diameter at base of 150 feet. 

 Immediately east of this is a rather irregular mound 46 feet in height, 

 and possibly other units of this remarkable cluster were even higher 

 and more extensive than these. A rectangular mound southeast of 

 the preceding was, according to the survey mentioned, 40 feet in 

 height, with its base extending 300 feet from north to south and 250 

 feet from east to west. This reference to several of the lesser works 



