442 GEOLOGY OF OHIO. 



Babb's quarry in the base of the Niagara. At either of these localities 

 the whole of the formation may be studied. 



The lower strata have the distinctly sandy constitution characteristic 

 of this formation, from which the stone is frequently called sandstone. 

 These strata are good fire-stones, and resist the action of fire as a back 

 wall in fire-places, for a generation, without softening or crumbling. But 

 the strata a few feet higher are burned into lime,«and make a medium 

 quality for building purposes, and, no doubt, a very good quality of 

 caustic lime for softening straw in the manufacture of paper. Some part 

 of the ten feet of massive stone furnishes good building material. This 

 stone has been obtained in Todd's Pork, but is expensive on account of 

 thickness of superincumbent stone of a poor quality which must be re- 

 moved before good stone can be reached. On Anderson's Fork, at Ogles- 

 by's quarry, the same stone is more accessible, and is the best building 

 stone obtained from this formation. The quality of this stone at Ogles- 

 by's has led some to refer it to the Niagara. But it has the hardness and 

 gritty character of the Clinton, and on surfaces which have been exposed 

 in the quarry to the action of atmospheric agencies for a period of several 

 years, it is seen to be composed almost wholly of a solid mass of broken 

 encrinitic stems. Aside from lithological characters, this stone at Ogles- 

 by's is in the Clinton horizon about mid-way from top to bottom, exclusive 

 of the iron ore in the uppei* part. The twelve feet from the top of the 

 Clinton is well seen from the under-strata at Babb's quarry, on Todd's 

 Fork, down stream to the locality of the iron furnace formerly erected to 

 work the ore. This twelve feet is highly fossiliferous throughout, but it 

 is only in a few feet at the bottom where the proportion of iron is large 

 enough to entitle it to the name of iron ore. In this part the imbedded 

 fossils are deeply colored by the iron. For some reason the furnace 

 erected here about twenty-seven years ago did not prove a success, and 

 was soon abandoned, although the quality of iron was regarded as very 

 good. The richest ore is a brittle stone, mostly composed of small, exte- 

 riorly smooth and shiny lenticular grains, reminding one of flax-seed. 

 The ore is easily crumbled in the hand, and contains numerous disjointed 

 crinoJdal disks, partially eroded. The species of fossils become more nu- 

 merous as we approach the higher strata. Sometimes the stone is highly 

 granular or crystalline, while still crumbling easily in the fingers, and 

 is less ferruginous, and the imbedded fossils become light-colored. The 

 iron ore occurs in considerable quantities, being exposed in an outcrop 

 along the slopes for several miles, and large quantities could be obtained 

 by stripping. If it were more convenient or nearer furnaces in operation, 

 it might become valuable to mix with other ores in making certain quali- 



