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drift of gravel, silt and sand continues to envelop the stratified rocks so completely that an exposure is rarely seen.

At Fort Inge, Nueces river, near the Southern Pacific Railway cross- ing, Frio river, at the crossing of the same railway, and at a point a few miles west of Uvalde, as well as at other points further north, near the Southern Pacific Railway, there are eruptions of basalt disturbing the Cretaceous rocks to such an extent as to prevent estimates being made for artesian water. Along the valley of the Nueces, Frio, Hondo, Sabinal and Medina rivers, above the mouths of their canyons through the Balcones plateau, for a distance not yet determined, artesian water can be gotten at reasonable depths, but between the line of hills north of the Southern Pacific Railroad, known as the Balcones escarpment and the Southern Pacific Railway, the water supply is from five hun- dred to seven hundred feet deeper than in the canyons.

BUILDING STONES.

Across the coast prairie, between Corpus Christi and San Diego, the rocks are friable sands and clays. Between San Diego and a point on the Texas Mexican Railway eight miles west of Los Angeles the country rock is, as has been stated, a white calcareous sandstone, rarely changing to a brownish yellow argillaceous sand, and a sand varying between the two. The white sand is generally an indurated stone, made so by the lime which fills the spaces between the grains of nearly transparent silica. It makes a beautiful building stone and is quite durable.

Overlying this white sandstone, but not of continuous extent, is a softer, almost pure tufaceous lime rock, which is employed in building stone walls by being cut into large oblong blocks by the saw or chisel. This stone is also used in house building, but is not as durable as the white calcareous sand rock. It may be of interest to state here that this tufaceous lime is geologically of quite recent deposit, for in- closed in it are the varieties of land shells now prevalent upon the surface.

From the Rio Grande, at Laredo, northward to Cotulla, there is a belt of brown sandstone in flaggy and thicker layers. The greater portion is friable and not well suited for a building stone, yet there are ledges in it that have proved to be stones of good quality as is shown by its use in Cotulla.

There are indurated beds of sandstone in the Carrizo Springs belt that are valuable for building purposes. The elegant court house at Carrizo Springs is built of it.

SOILS.

Classed according to their origin, there are three different characters of soils between Corpus Christi and the Southern Pacific Railway at Uvalde. These soils divide themselves as follows: