400 The Ohio Naturalist. [Vol. IX, No. 2, 



100-200 yards. It is almost level each way, but descends about 

 10 feet toward the river. It stands 20 feet above the river, and 

 a steep serrate bluff rises back of it. Its top is a structural plain. 

 All three of the above terraces have nearly continuous rock 

 fronts, and quarries have been opened in two of them. 



Next down the river is the long narrow terrace on the west 

 side just south of Rathbone. It is nearh' one-half mile in length, 

 descends 10 feet southward, but is almost perfectly level from 

 back to front. It stands 20-25 feet above the river with much 

 outcrop on terrace front. An excellent structural plain. 



A mile farther down stream and on the east side may be 

 found a rock terrace nearly one mile long and from 50 to 150 

 yards wide, 35-40 feet above the river, slopes gently toward the 

 river, and descends 15-20 feet in its length. Onlv one other 

 terrace studied is as high above the river as is this one. 



Opposite Dublin occurs a strong rock terrace about three- 

 fourths mile long and from 20 to 200 yards wide. Its top is 

 30-40 feet above the river and remarkably level, descending 

 southward or down stream about 10 feet in its length. Some of 

 the top is nearly bare; other parts are mantled with alluvium. 

 Terrace front is a rock outcrop. A quarry long ago opened in 

 the terrace near the Dublin bridge furnished building stone and 

 lime, +he latter being burned in kilns on the terrace. 



On east side of Scioto just south of Hayden's run, may be 

 found an interesting terrace over one-half mile long and 100-200 

 yards wide with its top full 40 feet above the river and very 

 level. In northern half is much washed, calcareous gravel, but 

 in southern half very little, usually none. Rock shows in terrace 

 front in several places. Bluff rising behind the terrace is of 

 limestone at base and deeply covered with drift. About in mid- 

 dle of bluff and 1.5-20 feet above the terrace top are fine glacial 

 striae on limestone.* These striae are about 800 feet above sea 

 level and 100 feet below the upland surface of the vicinity. Bed 

 rock occurs in Slate run to the south and in another run to the 

 north 25-50 feet above the striae. There seems to be a buried 

 valley here but it can not have been as deep as the present 

 Scioto valley. It must have been as deep as the top of the 

 striated ledge and it may have been as deep as to the terrace top. 

 The gravel being largely calcareous and only locally developed 

 is probably of post-glacial origin. Of course, if it were laid as 

 glacial outwash, the terrace top upon which it lies must represent 

 the bottom of an older valley. No striae have been found on 

 any of the rock terrace tops. The gravel has been opened and 

 worked at two points, and a quarry and crusher are in operation 

 in the southern part of the terrace. 



4 Reported by W. C. Morse in 190G. 



