363 



Two yards are estal lislied on tbe middle branch of the Rouge, in the 

 town of Nankin. At Wilkinson's, near Schwaizlmrg;, clay appears in 

 a stratum running along the hank, and is here two and a liaif feet thick. 

 Portions contain too niucb lime to be used with advantage. Good 

 bricks are manufactured of the clay taken from the river bottoms, at 

 Swift's, section 11. 



A bed of clay occurs in the town of Plymouth, section 4, from which 

 bricks and earthen ware are manufactured. It consists of strata of the 

 blue and yellow varieties, underlying probably 8 acres, with an averpge 

 thickness of 4 feet. A cap of sanJ, of 2 feet thickness, overlying, is 

 used in the manufacture. Sand and gravel underlie the bed of clay, 

 which are unfit for use from the lime contained. The bricks are of 

 good quality; l()0,Ot)0 were made this season, worth $5 per thousand. 

 The pottery ware receives a good glaze, and is durable. 



A bed of clay exists west of Plymouth corners, section 27. It is 

 supposed to cover 80 acres. Considerable lime is contained; 500,000 

 bricks are made from it each season. 



A bed of fine blue clay exists on section 11. The above were the 

 only deposits observed in this township. 



Blue clay appeai-s at the surface in the town of Canton, which is free 

 from lime. 



In the town of Huron a fine blue clay underlies the low lands bor- 

 dering Swan creek, at small depth, and frequently comes to the surface. 



The blue and yellow clays make their appearance at every bluff along 

 the Huron. They are in general very marly, and seldom free from 

 grit. A kiln was erected in a ravine of Woods' Creek, section 36, Van 

 Buren, but the clay proved so calcareous that the works were aban- 

 doned. 



LIMEUOCK. 



The great limerock formation, upon which the clay deposits of the 

 county rest, makes an outcrop, or appearance at the surface, through the 

 townships of Monguagon and Brownstown. It forms the bed of the 

 strait near its mouth as well as a found-ition to the islands. 



The most ea-terly point at which the rock appears above the level of 

 the water, is at Stony island. This is wholly constituted of the rock, 

 covered by only a few inches of soil. Limerock was formerly quarried 



