lvi REPORT OF THE STATE GEOLOGIST. 



CLAYS FOR BRICK, TERRA COTTA, AND DRAIN TILE. 



Clays suitable for brick making are found in all the different forma- 

 tions occurring in the State. All are not of equal value, and indeed 

 the brick made from some few are quite inferior, but the majority pro- 

 duce 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 m the clays. Selected clays, however, in these 

 localities produce brick of excellent color. The importance of this in- 

 dustry 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 pur- 

 poses, 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 becom- 



