DELAWARE COUNTY. 279 



its way to a lower horizon in the formation. It is necessary to add, 

 therefore : 



No. 8. (Seen above the bridge over the creek, east from Sunbury, and 

 near Boyd's qurrry ; also below the bridge at the top of the 

 bluff, right bank.) Irregular, rough, full of oblique divi- 

 sional planes, fragmentary, and sometimes concretionary, 



and in large masses 6 ft. 



" 9. Regular beds of 2 to 4 inches 4" 



" 10. Massive, or concretionary and irregular, with oblique divi- 

 sional planes, somewhat irony, with shaly deposits and part- 

 ings, seen 12 " 



The shale sometimes crumbles out of No. 10, leaving the heavier stone, 

 thus showing a tendency to caverns ; but these holes are not of great 

 depth, because of the unstable character of the rest of the rock. In some 

 places No. 9 is entirely lost, and Nos. 8 and 10 unite, making a very 

 rough and angular stone, with a thickness of twenty feet or more. The 

 bed of the creek here is made up of irregular angular pieces, instead of 

 flat, thin fragments, as at Mrs. Boyd's quarry and above. This section, 

 showing more or less of the beds of Nos. 8, 9, and 10, continues to form 

 the bluffs of the stream as far down as the dam. A few rods below the 

 dam the left bank is thirty-eight feet high, and is covered with a deposit 

 of travertine, or carbonate of lime, from the top to the bottom. There 

 is a flow of calcareous water over the bluff. This deposit is porous, and 

 must have at least an average thickness of three feet. Pieces of that 

 thickness have fallen down from the bluff. This carbonate has here no 

 stains as of iron, noticed at Iberia, in Morrow county, although it occu- 

 pies a similar situation geologically. This travertine has been burned, 

 and is found to make a very white and strong quicklime. 



The origin of the calcareous water which deposits this travertine is in- 

 volved in much doubt, there being no limestone in that neighborhood, 

 nor near that geological horizon. 



Just below this travertine, on the same side of the stream, is John 

 Landon's quarry, situated a short distance above the mill. This contains 

 the base of the section of rough stone already given (Nos. 8, 9, and 10), 

 and shows as follows : 



No. 10. Additional to No. 10 8 ft. 



" 11. Alternations of beds of shaly sandstone of 2 to 6 inches, 

 and of good beds of solid stone of 6 to 20 inches. The 

 individual layers of the slaty sandstone are not more 



than J of an inch thick* 22 " 



" 12. Shale 4 " 6 in. 



* These partings of slaty stone between the heavy beds aid in quarrying. 



