DELAWARE COUNTY. 313 



to soon pulverize and to disappear as dust, or to pass off by the action of 

 drainage water. With an occasional renewal, it may be used in that 

 way. A successful enterprise in the manufacture of hydraulic lime from 

 the lower portion of the black slate is in operation at Defiance, Ohio. It 

 is known as the Auglaize cement, and promises to become a rival of those 

 cements known in the principal markets of the country. 



The shale which overlies the black slate is very similar to the Olen- 

 tangy shale immediately below it. They are both worthy of being tested 

 thoroughly as fire-clay, or for the manufacture of a light-colored pottery, 

 or "Milwaukee brick." 



THE WAVEELY SANDSTONE. 



Of. the sandstone which comes next in the series very little need be 

 said. Its excellences are well known, and have been attested by the ex- 

 perience of builders throughout the country during the last forty years. 

 It is the same (geologically) as the famous Berea sandstone, and is in- 

 cluded within the Carboniferous rocks. Yet it has been observed to be- 

 come much finer-grained and better adapted to bases for monuments, for 

 grindstones and whetstones, and for ornamental architecture, in the cen- 

 tral counties of the State, than in counties further north. It is now be- 

 ing extensively used in the construction of bridges and culverts for the 

 new railroads in the eastern part of the county. Since the great con- 

 flagration at Chicago, sandstone is being more frequently employed for 

 walls of buildings than ever before. 



Brick and Tile. — The surface of the Drift clay is employed in the man- 

 ufacture of these articles by the following establishments : 



James E. Robinson, Ashley Brick. 



Wm. Robinson, Olive Green " 



John Knox, Trenton township " 



Jacob Williams, Harlem township " 



Rich- " " 



Eli Downing, " " 



Abram Springer, Delaware, " 



Joseph Haas, " 



Frank Curley '* , " 



Geo. Sherrer, " Tile and brick. 



James E. Robinson, Eden (last year) " 



Swan Roloson, 1J miles S. W. of Stratford " 



Wm. H. Edmonds, 1 mile west of Powell " 



Arthur Robinson, 3J miles west of Millville Tile. 



