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CLAYS FOR BRICK, TERRA COTTA, AND DRAIN TILE.

Clays suitable for brick making are found in all the different formations occurring in the State. All are not of equal value, and indeed the brick made from some few are quite inferior, but the majority produce good serviceable brick. The colors of the brick vary from yellow or cream color, such as are made at Austin, through various shades of browns and reds, according to the character of the clay. In Eastern Texas, as well as in the Carboniferous area, the brick are usually mottled from the amount of iron in the clays. Selected clays, however, in these localities produce brick of excellent color. The importance of this industry will be seen by the following statement of the aggregate of brick production for the year 1889, which was received from the operators of the brick kilns in answer to inquiries:

Brick burned during 1889, 95,000,000.

Many of the clays of the Tertiary examined during the past year are well suited to the manufacture of Terra Cotta and drain tile. These are found in the region covered by the Timber Belt Beds, as well as among the Fayette Clays. Those of the other areas have not yet been examined fully enough to determine their availability for these purposes, but it is probable that many Carboniferous clays will prove well adapted for them.

LIME.

As is well known, the lime made from the rocks of that horizon of the Cretaceous formation known as the Caprina Limestones (which is the most persistent bed of all the formation) is unsurpassed for quality. The fame of the Austin lime is well established. Other beds of the Cretaceous will answer well in lime making, although some of them contain too much clayey matter, or are otherwise unfitted for this use.

Lime is also made from the limestone of the other deposits, but none of these have been so successfully operated as those above mentioned. The reports received for 1889 gave a total production of 190,000 barrels.

CEMENT MATERIALS.

Cements are of two kinds, Natural, or Hydraulic, and Artificial, or Portland.

Natural, or Hydraulic, cement is made from certain clayey limestones, which, when burned and ground, have the property of setting or becoming