74

Peak beds, and their relation to each other, in Erath, Bosque, Parker and Wise counties.

Plant remains were taken from the sands and from the Alternating beds that will establish their identity as belonging to the Cretaceous age. For this reason these beds are included in this section.

BUILDING STONE.—In the Alternating beds there occur many grades of limestone. They vary from a smooth flag, which will prove useful for paving purposes, to those of sufficient thickness to be used in the construction of buildings, etc. In these beds the ledges of rock alternate in hard and softer strata, and as erosion progresses the hard limestones are left on the surface as blocks and flags ready for use in the construction of stone walls, for which they are admirably adapted. At the upper limit of the Comanche Peak bed there is a horizon, some twenty feet thick, of indurated chalky limestone, that has been used in the construction of houses, chimneys, etc. It can be sawed into blocks with ease, and is nearly perfectly white. It will not bear the stress required in the construction of very large buildings, but on account of the ease with which it may be worked, and its beauty, it will surely come into extensive use.

The Caprina bed which overlies the Comanche Peak rocks affords several varieties of good building stone. Near its base there is stone similar to that of the Comanche Peak bed, while near its center there are siliceous layers of various thickness, but they have not the beauty nor can they be so easily taken as the Comanche Peak limestone. At the upper limit of the flints belonging to the Caprina bed there is a chalk that is believed to be unsurpassed in beauty for use in ornamental construction when it is protected from the weather. It is pure white and of sufficient hardness to bear a fair polish. The Austin Marble and Washita Flags, which overlies the Caprina, contain valuable stone. The Austin Marble or Caprotina limestone, as it occurs in West Austin, bears an excellent polish and gives a pleasing effect because of the pseudomorphic fossils that occur in it in great numbers. The Washita Flags are stones of fine texture and are of considerable hardness. Some of them attain thicknesses sufficient to be used in the construction of houses.

SAND.—Sands for all uses in building, and probably suited for glass making, are to be found in the Trinity Division in any quantity. They are easy of access, and the analysis to be given in the Third Annual Report will definitely show their value.

BRICK CLAY.—The impure clays and sandy clays occurring in the Paluxy sands, near the southern limit in Lampasas county, appear to be well suited for brick manufacture. In the exposures places can be