M^GEE NOTES 0\ THE GEOI.OGV OF MACON CO., MO. 329 



sistent and easily recognizable diagnostic features by which they 

 can be readily discriminated wherever found. 



In following the exposures down Salt river from the Hann. 

 & St. Jos. railway to Hunt's coal-workirg it is found that the 

 strata have a southward inclination somewhat greater than the 

 slope of the river ; for not only does an identical and unmistaka- 

 ble rock-sequence — semi-dolomitic limestone, nodular black 

 shale, coal, and fire-clay, of constant thickness and uniform order, 

 and uniformly related to an underl}ing fossiliferous limestone of 

 peculiar character — appear at progressively decreasing heights 

 above the channel bottom, but the obscure yet unmistakable rock- 

 shelf formed in the bluffs by the limestone declines perceptibly 

 with respect to the river. The strata on East Fork have in like 

 manner a southward dip slightly greater than the river slope ; for 

 not only does a distinctive horizon iS feet above the channel bot- 

 tom at the Bevier bridge descend to the extreme bottom of the 

 channel at the Excello bridge, but the conspicuous sandstone 

 beds sink from mid-height of the bluffs in the latitude of Bevier 

 and Macon to only a quarter or third of the way up the slightly 

 higher bluffs in the latitude of Excello. 



Moreover, since the rock sequence exposed on Salt river is 

 duplicated so exactly on the East Fork as to leave no doubt 

 of its identity (the chief difference being a slight thinning of a 

 coal seam), and since the latter valley is some 35 or 40 feet 

 deeper than the former, it is e\ ident that the strata have a dip 

 westward ; and t!>is dip appears to be about equal to the south- 

 ward inclination. The true inclination is therefore southwestei'ly. 

 The mean rate may be roughly estimated at about 7 or S feet per 

 mile ; and the local inequalities are unimportant. This uniform- 

 ity in dip facilitates correlation of the detached sections. 



On seeking to so combine the various exposures as to form a 

 general section exhibiting the succession of strata in the region, 

 they fall at once into three groups : The first of these includes 

 the four Salt river sections, the Bevier bridge section, the Patton 

 creek section, and the Excello bridge section ; the second includes 

 the Claybank creek. May field. Excello road, Bevier, and Payson 

 sections; while the third includes the Broadhead section, the 

 Lower Brick-\ ard section, and the Macon boring. The first two 



