CLAYS OF MIDDLESEX COUNTY. 445 



It was well fused at cone 33 in the Deville furnace, so that it 

 represents a good fire clay of the refractory class. 



Some other clays in the vicinity of Woodbridge belonging to 

 this group, together with one from Sayreville, and their cone of 

 fusion are given in the following table : 



Fusion tests of refractory clays. 

 Locality 



No. Name. Cone. 



29 Top-sandy, W. H. Cutter, < 



27 v 

 32 v 



24 Pipkin clay, H. Maurer & Son, 32 v 



42 No. 2 fire clay, H. Maurer & Son, 33 v 



1 1 Mottled clay, J. R. Berry, 33 v 



14 Sandy clay, M. D. Valentine & Bros. Co., 29-30 v 



14 Top-sandy clay, M. D. Valentine & Bros. Co., 32-33 v 



14 Bottom-sandy, M. D. Valentine & Bros. Co., 33 v 



, 27 incipient 



17 Extra blue-sandy, Staten Island Clay Co., 1 



18 No. 1 tough clay, Staten Island Clay Co., 31 v 



70 Sandy clay, 33 v 



trifled 

 scous 

 scous 

 scous 

 scous 

 trifled 

 scous 

 scous 

 fusion 

 scous 

 scous 

 scous 



Florida Grove. — A number of fire-clay pits have been opened 

 up by McHose Brothers (Loc. 45) in the South Amboy fire-clay 

 beds, north of Florida Grove (Plate XLVII, Fig. 1). Several 

 samples were tested from here. 



The first of these was from a pit on the eastern side of the ex- 

 cavation, and known as a No. 1 sandy fire clay (Lab. No. 402). 

 It is a very gritty, yellowish-white clay of porous character and 

 slaked fast in water. The air-dried clay worked up with 26 per 

 cent of water, and the bricklets made from it had an air shrinkage 

 of 6.5 per cent. The tensile strength was low, averaging 45 

 pounds per square inch. Its behavior in burning was as follows : 



Burning tests of a No. 1 sandy Hre clay, McHose Bros., Florida Grove. 



Cone 5 10 



Fire shrinkage, 1.9 % 1.8 % 



Absorption, 15-39% 13-52% 



Color, yellowish white buff 



The clay was steel-hard at cone 8, and fused at cone 30. Its 

 composition was as follows : 



