CLAYS OF SALEM COUNTY. 499 



30 per cent, of water to temper it, and it had an air shrinkage of 

 8 per cent. Its average tensile strength was 90 pounds per square 

 inch. 



In burning, at cone 05, its fire shrinkage was 4 per cent., color 

 bright red, not steel-hard, and absorption 20.17 P er cent. At cone 

 03 the fire shrinkage was 5 per cent., color red., not steel-hard, 

 and absorption. 15.45 per cent. At cone 1 fire shrinkage 5.5 per 

 cent., color deep red, steel-hard, and absorption 13.48 per cent. 



It will be seen, therefore, that it does not burn as dense as 

 some of the other Alloway clays mentioned above. 



Fenwick. — Near Fenwick there is also' an abundance of this 

 clay. It was worked at one time on the flat near the station (Loc. 

 169), and the remains of a small brickyard are still to* be seen 

 there. While the deposit at the brickyard is probably not very 

 extensive, it is interesting to compare it with the one from, the 

 railroad cut north of Alloway, because it has. such a high tensile 

 strength, viz., an average of 327 pounds per square inch. At both 

 localities, however, the deposit is not strictly speaking the Allo- 

 way clay, but a secondary clay, which has been derived from the 

 Alloway by stream action at a much later date than the original 

 deposition of the clay. This re-working has greatly increased the 

 tensile strength. The clay at Fenwick has, however, a lower air 

 shrinkage, 7.6 per cent., when mixed with 29.7 per cent, water, as 

 compared to* 8.6 per cent, for the clay from the railroad cut (Loc. 

 164). At cone 03 the fire shrinkage was only 1 per cent., and the 

 absorption of the bricklet 11.86 per cent. It was steel-hard, and a 

 bright red color. Just northeast of Fenwick station there is a 

 great flat underlain by massive Alloway clay, with practically no 

 overburden. 



Big Mannington hill. — The clay is finely developed on the lower 

 slopes of Big Mannington hill, west of Fenwick, where extensive 

 banks could be opened up in the hillside with little or no trouble 

 with good drainage and with only a short haul to the railroad. 



Rid diet own. — In the railroad cut on the West Jersey R. R., 

 near Riddletown (Loc. 168), the Alloway clay is again well ex- 

 posed. Here at least 12 feet is to be seen, with 3 feet of over- 

 burden in the cut, but increasing up the slope away from the rail- 



