APPENDIX. 



[The following articles, read at the meeting in 18S3, were received (April, 1885,) too late for insertion in 

 their proper places, and are given here.— Secretary.] 



THE AGE OF KANSAS. 



BY B. B. SMYTH, TOPEKA. 

 ( Read before the Academy of Science, at Topeka, November, 1883.) 

 The altitude of the State of Kansas varies from 750 feet above the level of the sea 

 at the mouth of the Kavv, to about 4,000 feet near the northwest corner. The west line 

 of the State averages about 3,000 feet higher than the east line, thus giving an average 

 slope from west to east of about 7$ feet to the mile. The slope or fall in the western 

 part of the State is greater than in the eastern part. The average fall, however, of the 

 Kaw and Arkansas rivers, except in the western part of the State, is somewhat less than 

 7h feet to the mile, owing to their devious courses. 



ROCKS. 



The rock system of Kansas is exceedingly simple, commencing in the southeast cor- 

 ner with the sub-carboniferous, and ending in the northwest corner with the pliocene 

 tertiary. Over almost the entire State the rocks are monoclinal and dip gently to the 

 northwest at an average rate, in the central part of the State, at least double the aver- 

 age slope of surface to the southeast ; though further west there is scarcely any percep- 

 tible dip in most places, and in others slightly to the northeast. And so far as I am 

 aware, west of Topeka there is not a fault, fissure, fold or displacement of any conse- 

 quence*. Evidences of non-conformability are only very slight f. These things, how- 

 ever imperfectly known at present, will be better known after there has been a 

 systematic geological survey of the State. 



With the successive strata thus lying in natural and undisturbed positions, the calcu- 

 lation of a problem of time becomes a comparatively simple one, depending, for its accu- 

 racy, upon the care taken in the investigation, or the proper observance of the data at 

 hand. 



CALCULATION. 



Whether the strata of rock were as thick at the Missouri State line as at their pres- 

 ent outcrop in Kansas, I have no means of judging; but, in the absence of any opposing 

 testimony, we may assume that they were the same. Adopting the estimates of St. John 

 as most trustworthy, I find that the thickness of the outcrop from northwest corner to 

 southeast corner is over (5,000 feet, from which the average outcrop from the west line 

 to the east line may be figured at 5,000 feet. 



Now, considering that superposed strata to the amount of say 300 feet have been 

 washed away at the northwest corner, this would make an average of 670 feet washed 

 away along the west line of the State and 5,670 feet along the east line, thus making an 

 average of 3,170 feet, or fully three-fifths of a mile in thickness over the entire State, 

 equal to, since the State is 396 by 208 miles in area, a total of 50,000 cubic miles of earth 



* Mudge, 1st Bien. Rep. Kan. St. Bd. Agr. 



f Hav, present meeting, and St. John, 3d Bien. Rep. K. S. B. Agr. 



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