WARREN COUNTY.

The most extensively worked deposit in this county is the Hudson shale, which is being utilized at Port Murray (Loc. 282), on the D., L. & W. railroad (Pl. 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 unweathered 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:

It burned steel-hard at cone oI. 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 brick.

Washington.-Clay is known to occur in this county at Washington 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 I 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. 11 might make a fair grade of brick. No.

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.

2 might be available for the same purpose. No. 4 (Lab. 753) when burned to cone I is brownish red, steel-hard and has an absorption of 3.79 per cent. Another sample, No. 5 (Lab. No. 751), closely resembles the ochre in Tilton's yard, near Toms River. It is more plastic, however, and at cone I burned to a pinkish brick of steel-hard body, with a total shrinkage of 9.3 per cent. and an absorption of 8.66 per cent. Still another sample, No. 6 (Lab. No. 752), burns dark brown and steel-hard at cone I, with a total shrinkage of 10 per cent. and an absorption of 2.05 per cent.

Brass Castle.-A shallow, ferruginous clay, derived by wash from decomposing gneiss rock, occurs at Brass Castle, and is worked in a small way by John Benward for the manufacture of common brick. The clay was not tested.

Alpha. A yellow clay formed by the decomposition of the Portland cement rock (Trenton limestone formation), is dug at Alpha (Loc. 278) near the cement plant for the manufacture of brick. These are made by the soft-mud process, are of good color, and have been used in the new factory of the Alpha Portland Cement Company. The deposit is a shallow one, but covers a considerable area.

Danville.—Glacial clay is said to occur on the land of A. W. Davis, near Danville. The following is an analysis of it:

Chemical analysis of a clay. A. W. Davis, Danville.

Karrsville. Common brick have been made intermittently at Karrsville by David E. Cole,1 but the deposit is said to be of limited area and depth.

'N. J. Geol. Surv., 1898, p. 198.

APPENDIX A.

STATISTICS OF PRODUCTION.

New Jersey ranks third in the total value of its clay products, Ohio being first and Pennsylvania second. So steadily and rapidly has the output increased that since 1897 it has nearly doubled.

The value from 1895 to 1902 is given below, the figures being taken from the reports on Mineral Resources issued by the United States Geological Survey:

Value of clay products of New Jersey from 1895 to 1902

The detailed statistics of production taken from the same series

of reports are as follows:

b Stove lining not separately classified prior to 1899.

c Includes all products not otherwise classified, and those made by less than three producers, in order that the operations of individual establishments may not be disclosed.

d Includes pottery for New Hampshire.

• Also includes enameled brick valued at $177,128.

f Also includes enameled brick valued at $202,740.

The pottery industry of Trenton deserves some special mention on account of its size and importance. Thus, in 1901 and 1902 the value of the wares produced in Trenton alone was as follows:

The total value of the pottery production of the United States in 1901 was $22,463,860, so that Trenton produced 23.68 per cent. of this, exceeding the production of East Liverpool, the other great pottery centre of the United States, by 0.06 per cent. In 1902 Trenton produced 23.61 per cent. of the whole pottery product, exceeding East Liverpool by 0.41 per cent. The entire New Jersey pottery production for 1902, as reported by fifty-one firms, was valued at $6,192,959, which was 25.67 per cent. of the United States production.

The following list also gives the rank of New Jersey in the manufacture of other lines of clay products in 1901 and 1902, so far as was obtainable:

Rank of New Jersey in various lines of clay products.