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Texas, reaching to the New Mexico line, while northeast of these in the Permian region the constant recurrence of such names as Salt Fork, Salt Creek, etc., tell of the prevalence of similar conditions. In addition to the lakes and creeks from which salt is secured by solar evaporation we have also extensive beds of rock salt.

That which is at present best developed is located in the vicinity of Colorado City, in Mitchell County. The bed of salt was found by boring at 850 feet, and proved to have a thickness of 140 feet. A vein of water was struck below it which rises to within 150 feet of the surface. This is pumped to the surface and evaporated, and the resulting salt purified for commerce.

In Eastern Texas there have long been known low pieces of ground called "salines," at which salt has been manufactured by sinking shallow wells and evaporating the water taken from them. At one of these, Grand Saline, in Van Zandt County, a well was sunk, and at 225 feet a bed of rock salt was struck, into which they have now dug 300 feet without getting through it Many other similar salines are known in Eastern Texas and Western Louisiana, and the great deposits of rock salt developed at Petit Anse and Van Zandt under practically similar circumstances is certainly warrant enough for boring at the other salines for similar beds. Some of these localities are in Smith and Anderson counties.

In the Carboniferous area many of the wells yield salt water, sometimes strong enough to render them unfitted for any ordinary purpose, but no attempt has been made at their utilization. There are also brine wells in limited areas in Central Texas.

ALKALIES.

The source from which the salts of potash and soda can be obtained in Texas are:

The alkali lakes, where there is a large percentage of sulphate of soda (Glauber salts) deposited by the evaporation of the water. Its impurities consist of some sulphate of lime, or gypsum, and common salt.

THE BAT GUANO.—Nitre, or saltpeter, was made from this material during the late war, but the necessity for its manufacture ending, it was abandoned.

ALUM.

The best material for the manufacture of alum is found in the clay of the lignitic portion of the Timber Belt, or Fayette, Beds, which contain both pyrites and lignitic matter. Nearly all the material used in