Some of the results of their work which are here shown, give 

 a better idea of the geography of the mounds than can be obtained 

 in any other way. They show how the mounds are scattered over 

 the level plain which stretches east of the Mississippi river opposite 

 to St. Louis. This plain, known from very early times by the 

 white settlers as "The American Bottoms", is as much as a dozen 

 miles broad and seventy-five miles long. It was formerly a lake 

 bottom and is still occupied by numerous lakes and sw r amps which 

 are being drained by several extensive projects. The topographic 

 sketch map (Fig. 1) shows the location of the chief mounds in re- 

 lation to the eastern bluffs, East St. Louis, the Mississippi river 

 and St. Louis. The river is 400 feet above sea level in this local- 

 ity, the highest portions of the bluffs are 200 feet higher, and the 

 general line of the bluffs is at the 500 foot level. The top of 

 many of the mounds is about 440 feet. 



The first aerial picture (Fig. 2) shows the appearance of the 

 region looking east over St. Louis. The Mississippi river, flowing 

 to the right, with two of the four bridges which connect the Mis- 

 souri with the Illinois side, is in view. The railroads, cement 

 roads, canals and lakes are spread out upon the flat floor, and the 

 bluffs mark the eastern boundary of the plain. 



In none of the three views (Figs 3, 4 and 5) looking west from 

 over Collinsville does St. Louis appear through the haze, but the 

 Mississippi river is evident in the background and the lines of the 

 Pennsylvania and B. & O. railroads, the Collinsville hard road, 

 the Cahokia drainage project and the numerous lakes are easily 

 recognized. The nearer views (Figs 6-13) show the large mounds 

 clearly Monks', Merrill's, Schmidt's, Powell's and mounds num- 

 ber 51, 57, 60, etc. These mounds were numbered by Patrick about 

 1880 and his numbers have been adopted by *Moorehead (*"The 

 Cahokia Mounds"-, W. K. Moorehead, Uni. of 111. Bull. VoL XIX, 

 No. 35, April, 1922. Bibliograph see p. 40; also Transactions 111. 

 State Acad. Sci. Vol. IX, 1916, p. 83.) 



The numerous small mounds are difficult to distinguish from 

 straw stacks which are abundant in the fields. (The country has 

 been under cultivation for more than a century and the plowing 

 over the small mounds and past the large in a north, south, east, 

 west direction has given the mounds an artificial appearance)which 

 is well shown in the aerial photographs. Photos taken from the 

 ground give a truer idea of the actual horizontal outline (Figs. 

 14-19). 



The mounds are scattered mainly along the divide between 

 Canteen and Cahokia creeks on the north and Schoenberger creek 

 oh the south. Many of them are flat topped and of the same gen- 

 eral elevation (Figs. 14, 17, 18). Many show upstream faces which 

 are rather steep and the down stream edges which trail out into 

 long tongues (Figs. 17 and 19). (Their number, general contour 

 and location are such as to suggest a natural origin.) CBut the in- 

 ternal structure of several of the mounds does not seem to sup- 



