HARRISON COUNTY. 143 



and spread over much greater areas The mixture of clays and sands which 

 in Cass County lies in thin laminae of alternate clay and sand becomes more 

 of a clay and sandy clayey nature, the clay becoming more prominent. In 

 some places the clayey strata belonging to the stratified red and white sand 

 series of the Cass County beds show in Harrison a thickness of five or six feet. 



In Harrison County there are several extensive deposits of clay suitable 

 for manufacturing purposes. These clays range in color from a very dark 

 blue to a pale shade of the same color, from a dark iron brown to a pale 

 brick-red or a yellow, and from a drab gray to a pure white, and many beds 

 also extend in color from a pure black to a grayish *and rusty black. Many 

 of the Harrison County clays are too sandy and otherwise impure to be of 

 any use other than for the manufacture of the commonest and poorest grade 

 of ordinary building bricks, and others are so free from sand as to be prac- 

 tically useless in their native state, and in order to bring them into the requi- 

 site condition for manufacturing purposes require a liberal admixture of a 

 clean, pure sand. "Slick" clays when used without sand part with their con- 

 tained water too slowly, and mostly go to pieces in the drying. The best 

 clays for all practical purposes are those which contain a fair proportion of 

 sand. 



Some of the sandy clays of this county are to all outward appearances free 

 enough from iron and presumably other impurities to form a medium grade of 

 fire bricks and bricks suitable in every respect for the markets of the district. 

 Some of the less sandy and more aluminous clays are suitable for the manu- 

 facture of drain tiling, a good pressed front or ornamental brick, and may 

 probably be found by judicious mixing with other clays, all of which occur 

 in the county, suitable for the manufacture of terra cotta ware. A clay for 

 terra cotta ware requires to have the maximum of strength with the mini- 

 mum of shrinkage in the drying and burning, a combination of conditions 

 rarely found in clay from any one bed. In many portions of the county 

 there are extensive deposits of a gray, pinkish gray or white, white, and pale 

 lead colored clays, which lie near enough the surface for practical use, and 

 which are all sufficiently aluminous and plastic to form all the classes of the 

 ordinary earthenwaie of every day use. 



The clays of Harrison County may be distributed according to their uses, 

 as follows: 1, Brick clay or earth; 2, Fire clays; 3, Pottery clays; and 4, 

 Miscellaneous clays. 



1. BRICK CLAYS OR BRICK EARTHS. 



Under this heading it is proposed to group all the ordinary clay products 

 utilized in architectural or farming operations. These are ordinary building 

 bricks, pressed and ornamental and front bricks, terra cotta ware, and drain 

 tiling. 



