112 The Ohio Naturalist. [Vol. X, No. 5, 



massive blocks. The banks of the stream for several hundred yards 

 below the falls are strewn with huge blocks as if distributed for 

 some giant masonry. The blocks often measure S, 10 or even 

 12 feet in length. 



As seen at the fall and below the Lower Mercer is underlaid 

 by 4 feet of fire-clay and sandy shale but no coal. A short dis- 

 tance below the bridge this limestone dies out, shale appears, and 

 coaly shale comes in at the horizon of the base of the limestone 

 and further down becomes a definite bed of coal of 4 to 6 inches 

 thickness. This coal is traceable with a sandstone cover all the 

 way to the Mahoning River. At the forks of the highway and 

 just above the first bridge over Little Mill Creek this coal is 1 

 foot thick, lies at 1024, and is overlain by shaly micaceous 

 sandstone. At a point about midway between the above two 

 bridges on this creek this sandstone v/as formerly ciuarried. The 

 coal is seen to undulate and is certainly the coal referred to on 

 Island Creek near North Benton which at that point lies at 1012 

 above sea. It is certainly the coal belonging to the Lower Mercer 

 limestone but the latter is not seen anywhere to the westward on 

 either Little Mill Creek or the Mahoning River as far up the river 

 as the Benton-Deerfield highway. There is another thin coal to 

 be noted, however, in this connection which may easily cause 

 confusion. About 300 yards down stream from the mine on 

 Island Creek and at the bridge east of Benton Station this coal 

 lies in the creek bed at 997 above sea and about 8 inches thick. A 

 third of a mile northwest in the river bank just below the railroad 

 river bridge this coal is 7 inches thick and lies at 1000 above sea 

 or IS feet below rail on the bridge. It is seen at numerous other 

 points on the Mahoning and on Little Mill Creek and at 15 to 20 

 feet below the Lower Mercer Coal. The intervening rock is 

 largely sandstone. It is of interest to note here that two coals 

 occur below the Lower Mercer limestone at Lowellville; a 2-inch 

 layer 2 feet below, and an 18-inch bed 13^ feet below. 



It now remains to combine the several outcrops of limestone 

 seen in the Best's Station-North Benton-Little Mill Creek vicin- 

 ity into one section. From the data given it is clear that the 

 horizons of the Lower Mercer, Upper Mercer, and Howenstein 

 are found at North Benton. The mean elevation of the Lower 

 Mercer on Little Mill Creek is 1016, of the Upper Mercer 1037. 

 The Lower Mercer coal near North Benton lies at 1012 and were 

 the limestone present above it in usual thickness its elevation 

 would be 1015. The Upper Mercer at North Benton lies at its 

 highest piont at 1048 but its mean elevation is quite probably 

 about 1043. The Howenstein as seen at the cemetery lies at 

 1069. What is seen on Little Mill Creek confirms the identifica- 

 tion of horizons at North Benton, and the outcrops at North 

 Benton are sufficiently close together to be grouped in a single 



