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lower divisions of the Cretaceous and the Carboniferous areas; the basalt of such areas as Pilot Knob in Travis County; some of the sandstones or siliceous iron ores of the iron region of East Texas; the granites and other tough rocks of the Central Region are especially valuable, and similar rocks and the quartzites and porphyries of West Texas will also prove of value when transportation charges will admit of their use.

The occurrence of asphaltum in various portions of the State has already been noticed, and its use as paving material is well known.

For the construction of sidewalks, in addition to the material above mentioned, flagstones are found in various localities.

MATERIALS FOR PAINTS.

GRAPHITE has already been mentioned under refractory substances.

OCHRE.—This is a hydrated oxide of iron, usually containing more or less clay or sand and giving various shades of yellow, red, and brown. The most valuable is that which on preparation furnishes the color called Indian red. Ochres are found in connection with the geode and nodular ores of East Texas, forming centers of the geodes, and also deposits of limited extent. It is reported at many localities in the area covered by the Timber Belt Beds. In the Cretaceous area good ochres occur in Uvalde and Val Verde counties, in the latter of which one locality has been developed to some extent and the material shipped. Other deposits have been opened and worked very slightly for local use in different parts of the State.

BARYTES is found in Llano County, but has not been put to any use at all as yet.

OTHER ECONOMIC MATERIALS.

SULPHUR.

Specimens of native sulphur of a high degree of purity have been received from Edwards County, but up to the present no detailed examination has been made to ascertain its quantity or the condition of its occurrence.

SALT.

Like many of the other valuable deposits of Texas, the occurrence of the salt is widespread. Along the coast to the southwest are lagoons or salt lakes from which large amounts of salt are taken annually. Besides the lakes along the shore many others occur through Western