CLAYS OF BURLINGTON COUNTY. 389 



is reported to be underlain by clay, probably belonging to the 

 Cohansey formation. The clay is on property owned by Constant 

 Le Due. and is reported to- be from 1 3 to 1 5 feet deep, and covered 

 by a few feet of sand or gravel. The general character of these 

 beds can be inferred from what has already been said regarding 

 the Cohansey clays (p. 348). 



Pleistocene Clays. 



Clays belonging to the Pleistocene formation are worked at 

 three localities, one lying one-fourth mile southeast of Edgewater 

 Park station (Loc. 127), another at Martin's brickyard southwest 

 of Kinkora (Loc. 115), and the third at Scattergood's brickyard 

 north of Rancocas (Loc. 126). 



Edgeiivter Park. — The clay here forms a bed about 8 feet 

 thick, covered by 1 to 3 feet of loam and this in turn by 2 to 6 

 feet of wind-blown sand. The clay is colored bluish-black by 

 much organic matter, and is quite sandy due to numerous small 

 mica scales and quartz grains. The upper portion has been 

 yellowed by weathering. In working, about one-third loam has 

 to be mixed with the clay. 



The latter (Lab. No. 651), when examined in the laboratory, 

 was found to slake fast and mixed up with 22.6 per cent, of 

 water to a mass that was fairly plastic to' the feel. The air 

 shrinkage was 5.5 per cent., and the average tensile strength 185 

 pounds per square inch. In burning it behaved as follows : 



Burning tests of brick clay, Edgewater Park. 



Cone 05 15 



Fire, shrinkage, 1.8 % 2.5 % 5.8 % 



Absorption, 15-34% U-97% 2.86% 



Color, red deep red 



Condition, nearly steel-hard steel-hard 



Joseph Martin's brickyard (PL XLI, Fig. 2), is located half- 

 way between Florence and Kinkora (Loc. 115). The materials 

 used are a mixture of Raritan sandy clay, black sandy clay of late 

 Pleistocene age and a surface loam. This produces a mixture 



