380 CLAYS AND CLAY INDUSTRY. 



Burning test of Jos. Scott's clay, near Burlington. 



Cone 03 1 3 10 



Fire shrinkage, I % 2 % 3 % 5-6 %• 



Absorption, 15-94% i3-6i% 12.42% 2.19% 



Color, pale red light red red gray- 

 Condition, not quite steel-hard steel-hard 



On the north side of the creek, on the Hay property (Loc. 121 ), 

 Raritan clay is found underlying the flat bordering the streams. 

 A boring made at stream level showed : 



Loam (flood deposit), 2 feet.. 



Whitish-mottled clay, 10 inches. 



Red clay, white mottlings, 4 feet plus. 



The latter runs still deeper. In the strip parallel with the 

 creek there is 6 to> 8 feet of overburden, but back of this it in- 

 creases because the land rises. Trouble might also- be caused by 

 the creek water if the clay were dug below stream level. The 

 physical characters of the samples were as follows : 



The material (Lab. No. 640) worked up with 28 per cent, of 

 water to a fairly plastic mass whose air shrinkage was 5.3 per cent. 

 Its average tensile strength was 75 pounds per square inch. It. 

 was burned with the following results : 



Burning tests of clay from Hay property, Assiscunk creek. 



Cone 05 03 3 



Fire shrinkage, 0.7 % 3-7 % 6 % 



Absorption 18.04% 14-33% 10.12% 



Color, light pink reddish reddish pink 



Condition, not steel-hard steel-hard 



This is a clay of higher shrinkage than those found on the 

 opposite side of the bank. It might be used for foundry work 

 or terra cotta, but by itself is not sufficiently dense burning for 

 stoneware. 



Ficldsborougli. — The third type of Raritan clay, viz., that 

 which is used for common brick is worked near Fieldsborough. 

 It is used at S. Graham & Co.'s (PI. XL, Fig. 1) brick works, 1 

 mile south of Fieldsborough (Loc. 112). The clay forms a large 



