328 COUNTY AND REGIONAL GEOLOGY. 



6. RINGGOLD COUNTY. 



Boundaries and Area. Einggold county lies immediately 

 west of Decatur, which consequently borders its whole 

 eastern side, Union and Taylor counties bounding it respec- 

 tively upon the north and westj while the southern boundary 

 line of the State forms that also of the county. 



Like Decatur county, it is four townships in width east and 

 west and a little less than four from north to south. The 

 southern boundary line of the State, although intended to be 

 straight and uninfluenced by any geographical features, does 

 not exactly coincide in direction with east and west lines of the 

 linear surveys. Following the boundary line from east to 

 west, it is found to diverge to the southward of the section 

 lines of the surveys, amounting to about one mile in seventy. 

 In consequence of this divergence of the State boundary line, 

 Ringgold county, although nominally of the same size as 

 Decatur, really contains a little greater superficial area. It 

 amounts to about five hundred and forty square miles, or 

 three hundred and forty -five thousand, six hundred acres. 



Geology. If our knowledge of the geological character of 

 the strata that underlie the surface of this county, beneath its 

 thick covering of drift, were derived from all examinations 

 which it is practicable to make within its limits alone, we 

 should know very little with certainty about it; for so far as 

 is now known only two exposures of rock in place are to be 

 found within its boundaries. These are very slight exposures 

 both belonging to the Upper coal-measures, and consist in 

 each case of only a few layers of limestone. One of them is 

 upon section 1, township 70, range 28, in the extreme north- 

 east corner of the county, and the other is near its southern 

 boundary on section 19, township 67, range 29. It is 

 consequently more destitute of stone than any other county 

 of southwestern Iowa. Judging from these exposures and 

 from those observed in the adjoining counties, there is no 

 doubt that all the strata which immediately underlie the drift 

 belong to the Upper coal-measures. The drift here is very 



