336 COUNTY AKD KEGIONAL GEOLOGY. 



8. ADAIR COUNTY. 



Boundaries and Area. Adair, like Madison, and also 

 like the majority of the other counties of the third tier from 

 the southern boundary of the State, contains sixteen con- 

 gressional townships — four north and south and four east 

 and west. Its superficial area is consequently about five 

 hundred and seventy-six square miles, or three hundred 

 and sixty-eight thousand six hundred and forty acres. 



Drainage and Surface Characters. The Great Watershed 

 passes through Adair county, entering it from the north a 

 little east of its northwest corner, and leaving it a little 

 southward of the middle of its eastern boundary. The 

 Chicago, Rock Island, and Pacific railroad crosses the Great 

 Watershed almost exactly at the point where it enters Adair 

 county, which point, according to their levelings, is nine hun- 

 dred and seventeen feet above low water in the Mississippi 

 at Davenport, or about fourteen hundred and forty -five feet 

 above the level of the sea. After passing southeastward, 

 nearly as far as the center of the county, the watershed 

 sweeps abruptly to the eastward between the upper branches 

 of Grand and Middle rivers, and continues thus until it 

 makes its exit from the eastern boundary. The broad ridge 

 of upland that constitutes the Great Watershed, where it 

 enters the county, continues southward into Union county 

 between the East Nodaway and Grand rivers, both of which 

 are tributaries of the Missouri, and, although it thus becomes 

 a secondary watershed, it has actually a higher elevation 

 than the Great Watershed, which passes further to the east- 

 ward, as before explained. 



Thompson's fork, of Grand river, and both the East and 

 Middle Nodaways, have their rise in Adair county, and both 

 North and Middle rivers are only small prairie streams 

 where they enter its northern boundary. Even a few rivulets 

 of the upper branches of the East Mshnabotany reach 

 within its western boundary line. It will thus be seen that 

 this county, although not greatly elevated, is, nevertheless, 



