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0 A 11 KUNIFEKUUS LI M E8TON E S 



wedge-shaped interpolation is well seen at the next section, a little higher up 

 on the Des Moines, above Bald Point, where two thin seams of coal are seen 

 tapering away until they finally run out as they approach each other. (See Section 

 No. 60, D.) 



MARL AND DRIFT RESTING ON CARBONIFEROUS STRATA, DES MOINES. 



At a westerly bend of the Des Moines, here represented, designated on the chart 

 of the river, " Bald Point," the hills are about two hundred feet high ; laminated 

 sandstone forms their base, while the main body of the hill is composed of ash- 

 coloured, marly earth and drift. One mile above Bald Point, ledges of reddish 

 limestone extend to the height of five or six feet above the water-level ; and half a 

 mile further, or about eight miles above the Rapids, fragments of ironstone are 

 scattered on the shore near the water-level, mixed with a conglomerate of gravel 

 and sand, cemented by oxide of iron. A few hundred yards above this place, on 

 the left bank of the Des Moines, below the mouth of Honey Creek, ledges of soft 

 sandstones project from under the drift. Interposed between the beds is a wedge- 

 shaped siliceo-calcareous rock, which projects beyond the sandstones. 



The blacksmiths of Boone County have obtained some coal from a bed situated 

 on Section 5, Township 83 north, Range 26 west. From one to two miles above 

 the line between Townships 83 and 84, in latitude 42° 2', alternating beds of sand- 

 stone occur, overlying shale and coal ; and two to three miles higher two seams of 

 coal are seen above the water, one eighteen inches, and the other ten inches thick. 

 They are associated with shales, and shaly sandstones. Nodules of ironstone are 

 disseminated in the argillaceous beds below the eighteen-inch seam of coal. The 

 lowest bed, which decomposes into a fine, light-coloured potters' clay, gives out, when 

 applied to the tongue, a strong astringent taste. 



About three, hundred yards up the river, in nearly a northerly course, the lower 

 bed of coal is at the water-level, but rises again, in conformity to the undulating 

 depressions and elevations of the strata prevalent through this region. The beds 

 of coal thus attain an elevation of twenty to twenty-five feet above the water- 



