CLAYS OF WARREN COUNTY. 507 



WARREN COUNTY. 



The most extensively worked deposit in this county is the Hud- 

 son shale, which is being utilized at Port Murray (Loc. 282), on 

 the D._, L. & W. railroad (PI. LVI, Figs. 1 and 2). It is used for 

 the manufacture of fireproofing. The shale is weathered, but not 

 thoroughly softened, to a depth of 5 or 6 feet, and is capped by 

 4 to 5 feet of glacial drift. A mixture of the weathered and un- 

 weathered material is used. 



The lean character of the material can be seen by the fact that 

 it took only 18.5 per cent, of water to temper it and that it had an 

 air shrinkage of 2 per cent. Its average tensile strength was 51 

 pounds per square inch. Its behavior under fire was as follows : 



Burning tests of a clay shale near Port Murray. 



Cone 05 01 1 5 



Fire shrinkage, 1.6 % 2.4% 4.6% 7% 



Color, pale red red deep red deep red 



Absorption, 16.14% 14.67% 8.82% 3-26% 



It burned steel-hard at cone 01. Even if the shale were more 

 plastic, the material alone does not vitrify at a sufficiently low 

 temperature to make it of value for the manufacture of paving 

 trick. 



Washington. — Clay is known to occur in this county at Wash- 

 ington on the property of C. Blazer (Loc. 280). It is a fairly 

 plastic surface clay, derived by wash from: the disintegrated 

 gneiss. It worked up with 26.2 per cent, of water, and had an 

 air shrinkage of 6.3 per cent. At cone 05 its fire shrinkage was 

 1 per cent., absorption 14.07 per cent., color pale red, and bricklet 

 steel-hard, so that it ought to' produce a good common brick. 



Beattystown. — At the old Beattystown hematite mine (Loc. 

 283), on the property of L. T. Labar and neighbor, there occurs 

 a series of colored clays, several samples of which were sent the 

 Survey. Of these No. I 1 might make a fair grade of brick. N0 1 . 



1 These designations, No. 1, No. 2, etc., refer only to the numbers on the 

 samples when received. All the clays except No. 5 were somewhat sandy. 



