CLAYS OF CAMDEN COUNTY. 403 



A cemented sand layer was found under the clay in places. It is 

 said that the clay could be traced for a mile southeast of the pits. 

 It was sandy, and its color bluish white, buff, and chocolate. 



Analysis of clay near Conrad and Tansborongh. 



Sand 34.50 



Silica combined ( SiOO , 29.50 



Alumina 1 ( A1 2 3 ) , '. 23.30 



Ferric oxide (Fe-Os), 1.50 



Lime (CaO), 



Magnesia ( MgO ) , 



Potash (K-O), 1.77 



Soda (Na-O), 0.16 



Water (combined) (H2O) , 7.00 



Moisture 1.60 



99-33 



The composition would indicate a clay of buff-burning quali- 

 ties, but not a refractory one, for the per cent, of fluxes and sand 

 is too- high. (See Silica, p. 312, and Fire clays, p. 311). Its 

 composition resembles that of some stoneware clays. 



The crude clay could all be used for pipe according to Prof. 

 Cook, but for finer and ornamental terra cotta it was washed. 



Pleistocene. 



Fish House. — The deposits at Fish House (Loc. 137) have al- 

 ready been described in considerable detail in Chapter VI. 



Two large excavations have been made, from, one of which with 

 a working face varying from 15 to 2j feet in height, clay is now 

 dug at several points (PI. XLII, Fig. 1). 



The section here gave 



Section at Fish House. 



Sand, 6 ft. 



Yellow clay, 2-3 " 



Black clay, 24 " 



Yellow clay, ' 1 " 



Sand and gravel, somewhat cemented, ? " 



1 Including the titanic acid. 



