W£ST1 RS I IAL-1 l! U>8 01 I ill OHIO \ u.u ^ 5 



glomerate i*.<r which this could be misl iken. At certain points tra< 



ble impressions mnj also be found in these deposits. The) are 

 very indistinct, but quite resemble the impressions bo common in wme 

 parts of the conglomerate Beries, both in the eastern and the western 

 fields. Vsso iated with 1 1 » i — debris, when found along the Muldrnugh- 

 lull district,, we have a quantity of the \\a-t>' from 1 1 1 . - St Louis lime 

 stone, the uppermost purely calcareous member of our Subcarbonifen u< 

 rica This a — iation is strong!) confirmatory of the idea 

 that tlii — conglomerate is thai or 1 1 » * - coal period. 

 The whole of the Green river basin in the counties of Adair. Green, 

 fe, and parts ol others, has its hill-tops covered bj the beds of 

 Warsaw division of the 8t Louis group. From this level to the 

 (•bearing series, where thai is left in the region, to the 

 trict, i- not over one hundred and fifty feet In the dis- 

 trict t.> the west, the thickness of the St Louis is greater, being about 

 two hundred and fifty feet on the average. Above the St Louis the 

 idstone, which i- the transition Beries from 1 1 » » - deep sea lime- 

 below to the land beds above, is perhaps about one hundred feet 



thick. In its upper pari we have some thin coal Beams, oi f which is 



about eight inches thick, and i- found over an extensive section in the 

 d-ficlds; so we are safe in asserting that there is only required 

 t,i be restored to this district of the upper Green river a total thickness 

 of from two hundred to two hundred and fifty feet to return the car- 

 boniferous horizon to it [a it likely that tln-< thickness of deposits has 

 disappeared from tlii< region? It seems to me that we are forced to give 

 an affirmative answer to 1 1 1 i - question. It needs but a glance at the con- 

 ditions of thi^ district to make it clear that it i- wearing down with 

 rapidity compared with other parts of the Mississippi Valley. We know, 

 from the labors of Humphreys and Abbott that the erosion of the M ■ 

 sissippi N nlle> i- now going on at 1 1 » • * rate of one foot in seven thousand 

 \ ■ sion i- in tin- main proportionate to the amount of 

 rainfall, it i* doubtless about twic< it in tlii- section of the Ohio 

 Vallej the whole Mississippi drainage Bystem. I am sat- 

 isfied t li.it one foot in three thousand five hundred years is no1 too much 

 to allow for the ablation of the surface of this region. At this rate the 

 tion of the three hundred feet of beds wlii«!i I believe hav< 

 ! from this district between 1 1 1 « - coal-fields since th nglomcrate 



