McUhematical a)td Geological Papern. 5il 



1. Were the Wreford limestone still at Emporia it would 

 have an elevation of about five hundred feet above the Em- 

 poria series of limestones ; therefore five hundred feet of rock 

 strata has been removed by the erosive agents from central 

 Lyon county since the "Flint Hills" were over this locality. 

 If the average rate of denudation was that of the Mississippi 

 basin, one foot in about five thousand years, then it has taken 

 two million five hundred thousand years to remove these five 

 hundred feet. The average recession westward of the "Flint 

 Hills" during this time has been about fifteen miles, except in 

 the river valleys, where the recession has been much greater. 

 To have made a recession of sixty miles would have required, 

 at this rate, ten million years. This confirms the estimated 

 time of recession, twelve million years, as the width of the 

 belt covered with chert gravel is more than- sixty miles rather 

 than under. 



2. While Mr. Alva J. Smith was superintending the exca- 

 vating necessary for a sewage disposal plant near Council 

 Grove, Morris county, in the bottom lands bordering the 

 Neosho river, he found several interesting relics of a previous 

 civilization in undisturbed river silt and gravel. Resting on 

 a stratum of limestone on a level with the bed of the river Mr. 

 Smith found about three feet of blue clay in which were sticks 

 of wood and the faint impression of a leaf. On this blue clay 

 rests three feet of chert gravel. In the lower part of the 

 gravel he found a spear head of chipped flint of crude work- 

 manship, and an arrow point of the same material but of bet- 

 ter shape. On the gravel rests twenty feet of river silt, con- 

 stituting the main thickness of the bottom land, except at the 

 margin, where it thins out and the gravel emerges. The latter 

 stretches as a thin sheet up the slope of the river bluff to the 

 top. where it thickens and caps the blufl!". In the excavation 

 in the bottom land, several rods back from the river, Mr. Smith 

 discovered in the silt, thirteen feet below the surface, the 

 bones of a bison, and ten feet deeper he found another arrow 

 point of chert (flint). A tree stump on the surface of the 

 bottom land near the excavation showed one hundred and 

 seventy-five annual rings, and yet its roots showed scarcely 

 any burial by silt from the river overflows. 



3. While excavating for a well in the river bottoms at 

 Eureka, Greenwood county, the workmen found just above the 



