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KANSAS UNIVERSITY QUARI ERLY, 



But there is one point in connection with this subject which is 

 difficult to understand. The strata as now observable dip uniformly 

 to the west. If they were laid down in a horizontal position the only 

 way this could be brought about would be for the sum total of the 

 uplift to the east to exceed that to the west. If during the period of 

 formation a line of stationary position was maintained along the 

 shores of the then existing Mississippian series, to the west of which 

 there was a general subsidence, but each rock system formed on the 

 horizontal, it would seem that no movements could leave such forma- 

 tions higher vertically than the border of no variation along the coast 

 without causing such formations to dip to the east. A vertical sec- 

 tion drawn normal to the line of no variation would cut it in a point 

 which may be looked upon as the projection of an axis of rotation. 



This is best explained by reference to figure i. Let O be the inter- 

 section of the vertical section with the marginal line of no oscillation 

 during the period of Coal Measure time, and the lines OA, OB, OC, 

 and OD represent different systems. Now if OA was horizontal when 

 formed it might be brought to its present position by continuous 

 subsidence to the left; so also might OB, OC, etc., so that they would 

 all dip to the west. But when the final period of elevation came it 

 would be impossible to lift the western portion of OD to a greater 

 height than that to which O was carried without causing it to dip 

 to the east. If we suppose that the point O was elevated looo feet 

 above the sea level, then D may also be lifted to that height without 

 passing beyond the horizontal. But in Kansas the present surface 

 in the Flint Hill region in places reaches 1700 feet or more above sea 

 level, and yet the uppermost surface strata dip westward nearly 10 

 feet to the mile, which, were they extended eastward would take them 

 more than 1500 feet above the highest hills in the Ozark uplift, a 

 position which very probably they never occupied. 



But if we assume that the different systems were deposited on an 

 ocean floor itself inclined to the west, and add the subsidence already 



