THE NIAGARAN FORMATIONS OF WESTERN OHIO 337 



Thickness ThTSss 



No. . Feet Inches Feet Inches 



to represent the Belfast, since he wrote, "If 

 they [the layers] represent the Belfast bed of 

 more eastern sections, as is believed to be the 

 case, they certainly have changed considerably 



from the typical form of the rock." 1 2 8 6 8 



1. Richmond formation. — Rather thin-bedded 

 blue rock to shaly layers, perhaps with sandy 

 to calcareous composition. This zone extends 

 to water level and blue shale is washed out of a 

 pit that has been dug still deeper by the water. 

 About 5 feet of this zone are shown in the bank 

 on the southern side 4 o 4 o 



The foregoing section gives 26 feet 7 inches for the thickness of 

 the Brassfield limestone. This agrees fairly well with the estimate 

 based upon the thickness of the Brassfield on the northern bank 

 at the falls and the section in the Big Four Railway cut west of the 

 station on the southern side of the creek. Mr. W. Z. Miller, my 

 assistant, made the top of the Brassfield limestone in the railway 

 cut about 7 feet higher than the top of the ledge on the northern 

 bank of the creek, which gave 28^ feet for the total thickness of the 

 Brassfield limestone on Ludlow Creek. 



The general section of Ludlow Creek is continued by the section 

 of the western wall of the Colonel Samuel B. Smith quarry and the 

 bank above it, below the house of Patrick Gallagher. 



Section of Western Wall of the Smith Quarry 



Thickness ThTckne'ss 



No. Feet Inches Feet Inches 



26. Laurel limestone. — Top of bank just below 



house of Mr. Patrick Gallagher. Light- to 



bluish-gray rock in fairly even layers varying 



from 2 to 5 inches in thickness. The upper 



weathered ones are rather buff and finely 



porous 3 5 2 4 10 



25. Partly covered interval. Light- to brownish- 

 gray, rather thin-bedded, dolomite 2 8 21 5 



24. Osgood beds. — Partly covered zone; but at top 



bluish-gray shale to shaly limestone 1 3 18 9 



1 Journal of the Cincinnati Society of Natural History, XVIII (1896), 182. 



