379 



but slabs are said to be obtainable of size sufficient for door and window 

 silb, &c. 



Limerock forms the bed of Otter Creek, at Winchester, and for the 

 distance of eight miles above. It is hard, of a bluish gray color. 



Following the range south-west, we find a ridge or hillock composed 

 of limerock, on sections 3 1 and 32, of Lasalle, and 1 and 2 of town- 

 ship of Erie. It appears over an area of more than a square mile, 

 having an elevation of about ten feet above the level, on the south. The 

 stone, 80 far as penetrated, (five feet,) is of a light color, striped, and 

 portions fissile. 



Limerock is met with, in the same range, at not less than four places, 

 in the township of Bedford. In the bed of Bay Creek, a small quarry 

 has been opened. 



Near the centre of the township it appears twice over surfaces of two- 

 thirds a square mile. These have been penetrated several feet, and are 

 found to consist of a very silicious rock, composed of an aggregate of 

 grains of quartz cemented by lime. The upper portions, which lie in 

 loose masses, are calcareous and are alone suitable for burninof. 



At the south-west corner of section 30, limerock appears at the sur- 

 face, and in the bed of Hallway Creek. This continues at intervals for 

 a mile west, and in a south-west direction, following Ottawa Creek, to 

 Whiteford, in Ohio. It underlies the intermediate spaces at a depth 

 probably not exceeding five feet. A continuation of the ledge may 

 also be traced north, along the whole eastern border of township of 

 Whiteford. The upper portions only could be observed, which appear- 

 ed to be a pure, compact limestone. 



No fossils were found in this range, except Terebratula, at Newport 

 and Stony Point. 



Another range or series of outcrops passes through the centre of the 

 county, in a direction parallel to the former. It must be considered as 

 the overlapping edge of a portion of the limerock formation, superim- 

 posed upon that whose outcrop forms the range first mentioned. This 

 portion of the formation includes several strata of a very silicious char- 

 acter, approaching in several instances, almost to pure sandrock. 



Stone of this description makes its appearance six miles northwest 

 from Monroe, and was traced over a surface of one half a square mile. 

 It disintegrates readily, where exposed, into a pure silicious 8«nd, which 



