GEOLOGY OF SOUTHWESTERN IOWA. 341 



Nodaway, the next exposure to be found in this part of the 

 county is near Harader's mill, three miles north of Quincy, 

 where a few feet of clayey shales and impure limestone rest 

 upon a bed of coal about eighteen inches thick. The stone is 

 very small in quantity, and not of very good quality, but 

 owing to the scarcity of stone in this region, it has been 

 taken out to some extent for common use, and the coal has 

 also been mined there, but not extensively. Three miles 

 farther down the valley, and two miles west of Quincy, the 

 same bed of coal has been quite extensively mined at several 

 points within half a mile of each other. 



The exposures are upon, or near the banks of the river; the 

 following described strata being exposed in the left bank, 

 near the bridge : 



Section near Quincy. 



No. 10. Bluish, shaly limestone 20 inches. 



No. 9. Dark colored shale 8 inches. 



No. 8, Coal , 20 inches. 



No. 7. Light bluish, shaly, fossiliferous clay 20 inches. 



In the year 1866, Messrs. Barnett and Smith commenced 

 sinking a shaft within a few rods of this locality, with the 

 hope of finding a deeper and better bed of coal. The follow- 

 ing is Mr. Smith's statement of the strata passed through: 



Barnett and Smith's Shaft. 



No. 6. Dark gray, clayey limestone 5 feet. 



No. 5. Dark colored carbDnaceous shale 2 feet. 



No. 4. Dark colored fossilifjrous limestone 1 foot. 



No. 3. L ; ght, gray limestone, with dull fracture 5 feet. 



No. 2. Gray, clayey shale 6 feet. . 



No. 1. Concretionary clayey limestone, alternating with clayey 



shale , 25 feet. 



The enumeration of the strata passed through at the shaft 

 of Barnett and Smith, commences at the top (No. 6), with the 

 stratum which immediately underlies the lowest member of 

 the section measured upon the bank of the river, (No. 7). 



